Excel Cell Pixel Coordinates

2023-11-26 02:38 UTC gpt-4 Open in ChatGPT ↗

Sure, I can guide you through the steps needed to get the exact screen pixel coordinates of an Excel cell. This task indeed involves a mix of VBA, C++ programming, and calling Windows API functions. Here’s a high-level overview of the steps you’ll need to follow:

1. Determine the Cell’s Position Within Excel

VBA: Use VBA to get the position of the cell within Excel. This can be done by using the Top and Left properties of the Range object representing the cell.

2. Get Excel Window Handle

Windows API & VBA: Use the Windows API from VBA to get the handle (HWND) of the Excel application window. This involves using functions like FindWindow or FindWindowEx.

3. Obtain Excel Window Position and Size

Windows API & VBA: With the window handle, use API functions like GetWindowRect to retrieve the position and size of the Excel window.

4. Factor in Window Decorations and Excel Ribbon/Toolbars

Windows API & VBA: Adjust for window borders, title bar, ribbon, and other toolbars. This may require additional API calls to accurately calculate their sizes.

5. Calculate Absolute Screen Position

VBA/C++ Calculation: Combine the information from steps 1-4 to calculate the cell’s absolute position on the screen.

6. Consider Screen Resolution and Scaling

Windows API & C++: Use API functions like GetDeviceCaps to determine the screen resolution and scaling factors, which are necessary to convert the position to pixel coordinates accurately.

7. Implementing in C++

If you wish to implement some parts in C++, you can create a DLL in C++ that interacts with the Windows API and exposes functions that can be called from VBA. This involves more advanced programming.

8. Error Handling and Edge Cases

Consider different scenarios like multiple monitors, varying DPI settings, and different Excel versions.

Detailed Steps:

VBA to Get Cell Coordinates:

Dim rng As Range
Set rng = ThisWorkbook.Sheets("Sheet1").Range("A1")
Dim cellTop As Double, cellLeft As Double
cellTop = rng.Top
cellLeft = rng.Left

VBA to Get Excel Window Handle:

Declare PtrSafe Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As LongPtr
Dim hwnd As LongPtr
hwnd = FindWindow("XLMAIN", Application.Caption)

VBA to Call Windows API for Window Position:

Type RECT
    Left As Long
    Top As Long
    Right As Long
    Bottom As Long
End Type

Declare PtrSafe Function GetWindowRect Lib "user32" (ByVal hwnd As LongPtr, lpRect As RECT) As Long
Dim rect As RECT
GetWindowRect hwnd, rect

Adjusting for Window Decorations: This part may require additional API calls to get the sizes of toolbars and borders.
Final Calculation: Combine the cell position within Excel with the Excel window’s position on the screen, adjusting for any decorations.
Get Screen Resolution in C++: Use the Windows API in a C++ program to get screen resolution and scaling factors, if necessary.
Interoperability Between VBA and C++: If you create a C++ DLL, you can call its functions from VBA using Declare statements similar to the Windows API calls.
Testing and Validation: Test on different setups to ensure accuracy.

This is a complex task that requires a good understanding of both VBA and Windows API programming. It’s important to test extensively, especially considering the variety of Excel and Windows configurations.

You’re right, determining the size and position of window decorations, ribbons, and toolbars in Excel using the Windows API is a crucial step for accurate positioning. Here’s how you can approach this:

Determining Decorations, Ribbons, and Toolbars Size

Use Windows API to Get Non-Client Area Sizes: The non-client area of a window includes the title bar, menu bar, and borders. You can use the GetSystemMetrics function to get the sizes of these elements. The metrics of interest would be SM_CXFRAME, SM_CYFRAME, SM_CYCAPTION, etc., for the width of the window frame, the height of the window frame, and the height of the title bar, respectively.
Calculate Ribbon and Toolbar Heights: Excel’s ribbon and toolbars are part of the client area, so their height must be subtracted from the total client area height to get the usable area height. Unfortunately, there’s no direct API to get the height of the ribbon and toolbars. A common approach is to use VBA to approximate these sizes. For example, the ribbon height can be estimated by subtracting the Application.UsableHeight from the Application.Height.
Account for Excel’s Formula Bar and Status Bar: Similar to the ribbon and toolbars, you’ll need to estimate the heights of the formula bar and status bar if they are visible. This can also be done by comparing Application.UsableHeight with the total Application.Height.

Sample Code Snippets

Get System Metrics for Non-Client Area (C++/VBA):

C++:

int frameWidth = GetSystemMetrics(SM_CXFRAME);
int frameHeight = GetSystemMetrics(SM_CYFRAME);
int captionHeight = GetSystemMetrics(SM_CYCAPTION);

VBA:

Declare PtrSafe Function GetSystemMetrics Lib "user32" (ByVal nIndex As Long) As Long
Const SM_CXFRAME As Long = 32
Const SM_CYFRAME As Long = 33
Const SM_CYCAPTION As Long = 4

Dim frameWidth As Long, frameHeight As Long, captionHeight As Long
frameWidth = GetSystemMetrics(SM_CXFRAME)
frameHeight = GetSystemMetrics(SM_CYFRAME)
captionHeight = GetSystemMetrics(SM_CYCAPTION)

Estimate Ribbon and Toolbar Heights (VBA):

Dim ribbonHeight As Long
ribbonHeight = Application.Height - Application.UsableHeight
' Note: This is an approximation and might not be accurate for all Excel versions.

Combining These Measurements

After getting these measurements, you will need to combine them with the cell’s position within the Excel application window and the Excel window’s position on the screen. This will give you the absolute position of the cell in screen coordinates.

Considerations

Excel Version and UI Customization: Different versions of Excel may have different UI elements, and users can customize the UI (like minimizing the ribbon), which can affect these measurements.
DPI Scaling: On high-DPI displays or systems with scaling factors applied, you will need to adjust these measurements accordingly.
Testing: It’s important to test your solution across different versions of Excel and Windows, especially considering the variety of user configurations and display settings.

This approach requires a good deal of low-level programming and understanding of both the Windows API and Excel’s object model. The accuracy of your measurements can be influenced by various factors, including user settings and Excel versions, so thorough testing is essential.

Combining everything into a precise VBA code requires several steps and a good understanding of Windows API calls. Below is an example VBA code that attempts to combine these steps. Please note that this is a basic example and might need adjustments based on your specific Excel and Windows environment.

VBA Code to Get Cell Position in Screen Coordinates

Option Explicit

' Windows API Declarations
Declare PtrSafe Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As LongPtr
Declare PtrSafe Function GetWindowRect Lib "user32" (ByVal hwnd As LongPtr, lpRect As RECT) As Long
Declare PtrSafe Function GetSystemMetrics Lib "user32" (ByVal nIndex As Long) As Long

' Constants for System Metrics
Const SM_CXFRAME As Long = 32
Const SM_CYFRAME As Long = 33
Const SM_CYCAPTION As Long = 4

' RECT Structure
Type RECT
    Left As Long
    Top As Long
    Right As Long
    Bottom As Long
End Type

Sub GetCellScreenPosition()
    Dim hwnd As LongPtr
    Dim rect As RECT
    Dim cell As Range
    Dim cellLeft As Double, cellTop As Double
    Dim windowLeft As Long, windowTop As Long
    Dim frameWidth As Long, frameHeight As Long, captionHeight As Long
    Dim ribbonHeight As Long
    Dim screenLeft As Long, screenTop As Long

    ' Get the handle of the Excel window
    hwnd = FindWindow("XLMAIN", Application.Caption)
    If hwnd = 0 Then
        MsgBox "Excel window not found.", vbCritical
        Exit Sub
    End If

    ' Get the position and size of the Excel window
    GetWindowRect hwnd, rect
    windowLeft = rect.Left
    windowTop = rect.Top

    ' Get the system metrics for frame and caption
    frameWidth = GetSystemMetrics(SM_CXFRAME)
    frameHeight = GetSystemMetrics(SM_CYFRAME)
    captionHeight = GetSystemMetrics(SM_CYCAPTION)

    ' Estimate the ribbon height
    ribbonHeight = Application.Height - Application.UsableHeight

    ' Set the target cell
    Set cell = ThisWorkbook.Sheets("Sheet1").Range("A1")  ' Change as per your sheet and cell

    ' Get cell position within Excel
    cellLeft = cell.Left
    cellTop = cell.Top

    ' Calculate cell's absolute screen position
    screenLeft = windowLeft + frameWidth + cellLeft
    screenTop = windowTop + frameHeight + captionHeight + ribbonHeight + cellTop

    ' Output the screen position
    MsgBox "Cell position on screen: Left = " & screenLeft & ", Top = " & screenTop
End Sub

How It Works

Windows API Calls: The code uses FindWindow, GetWindowRect, and GetSystemMetrics to get the Excel window’s details and system metrics.
Cell and Window Coordinates: It calculates the position of a specified cell (A1 in this example) within Excel and the Excel window’s position on the screen.
Adjustments for Decorations: The frame, caption, and ribbon heights are accounted for to adjust the cell’s position.
Screen Coordinates: The final screen coordinates are calculated and displayed in a message box.

Customizations and Testing

Cell and Sheet Reference: Change ThisWorkbook.Sheets("Sheet1").Range("A1") to point to your specific sheet and cell.
Ribbon Height: This is an approximation. If your Excel UI is heavily customized, you may need to adjust this part.
Testing: Test this code in your specific environment. Different screen resolutions, DPI settings, and Excel versions may affect the output.

This code provides a starting point but may require adjustments and fine-tuning based on your specific requirements and environment.

In Excel VBA, the CellLeft and CellTop properties (retrieved from the Left and Top properties of a Range object, respectively) are defined in points. A point is a unit of measurement typically used in typography and graphic design, and in the context of Excel, it is used to measure distances within the application’s window.

To clarify:

1 point is approximately 1/72 of an inch.
The Left property of a Range object returns the distance, in points, from the left edge of column A to the left edge of the range.
The Top property returns the distance, in points, from the top edge of row 1 to the top edge of the range.

When you’re working with screen coordinates (which are usually in pixels), you might need to convert these point values into pixels. This conversion can depend on the display DPI (dots per inch) settings and the application’s scaling settings. In standard displays, a rough approximation can be to use the fact that 72 points are roughly equal to 96 pixels (standard screen resolution), but this will vary with different screen DPI settings.

For more accurate conversion, you can use Windows API functions or application-specific methods to determine the current DPI settings and scale the point measurements accordingly. This is particularly important in modern environments where high-DPI displays are common.

To accurately calculate the screen pixel coordinates of an Excel cell, incorporating the conversion of points to pixels is indeed necessary. The conversion depends on the DPI (Dots Per Inch) setting of the display. In Windows, standard DPI settings are typically 96 DPI, where 1 point is equal to 1/72 of an inch, and 1 inch is 96 pixels. However, this can vary with different DPI settings, especially in high-resolution displays.

To account for this in the VBA code, you can add a function to get the scaling factor based on the current DPI settings and use it to convert CellLeft and CellTop from points to pixels. Here’s how you can modify the code:

1. Get DPI Scaling Factor

You can obtain the DPI scaling factor using Windows API functions. However, directly accessing these functions from VBA is complex. A simpler approach is to use the screen’s scaling factor relative to the standard DPI (96 DPI).

2. Modify the VBA Code

Here’s the modified part of the VBA code to include DPI scaling:

' ...

' Additional Windows API Declarations
Declare PtrSafe Function GetDC Lib "user32" (ByVal hwnd As LongPtr) As LongPtr
Declare PtrSafe Function ReleaseDC Lib "user32" (ByVal hwnd As LongPtr, ByVal hDC As LongPtr) As Long
Declare PtrSafe Function GetDeviceCaps Lib "gdi32" (ByVal hDC As LongPtr, ByVal nIndex As Long) As Long
Const LOGPIXELSX As Long = 88

' Function to get DPI scaling factor
Function GetDPIScaling() As Double
    Dim hDC As LongPtr
    hDC = GetDC(0)
    If hDC = 0 Then
        GetDPIScaling = 1
        Exit Function
    End If

    Dim dpi As Long
    dpi = GetDeviceCaps(hDC, LOGPIXELSX)
    GetDPIScaling = dpi / 96   ' 96 DPI is the standard
    ReleaseDC 0, hDC
End Function

Sub GetCellScreenPosition()
    ' ...

    ' Get DPI scaling factor
    Dim dpiScaling As Double
    dpiScaling = GetDPIScaling()

    ' ...

    ' Convert cell position from points to pixels
    screenLeft = windowLeft + frameWidth + (cellLeft * dpiScaling)
    screenTop = windowTop + frameHeight + captionHeight + ribbonHeight + (cellTop * dpiScaling)

    ' Output the screen position
    MsgBox "Cell position on screen: Left = " & screenLeft & ", Top = " & screenTop
End Sub

Explanation

DPI Scaling Factor: GetDPIScaling function calculates the DPI scaling factor based on the current screen DPI setting.
Conversion of Points to Pixels: cellLeft and cellTop are multiplied by the DPI scaling factor to convert the measurements from points to pixels.
Combining with Window Position: The pixel-converted cell position is then combined with the window position and adjusted for window decorations to get the absolute screen position.

Considerations

High-DPI Displays: This approach is more accurate for high-DPI displays and varying scaling settings.
Testing and Validation: It’s important to test this in your environment, as display settings can significantly affect the results.

Creating a borderless window that is invoked from VBA by calling a C++ DLL involves several steps. You’ll need to write a C++ DLL that creates a borderless window, and then use VBA to call functions from this DLL. Here’s a high-level overview of the process:

Step 1: Create a C++ DLL

Set Up a C++ Project: Start by setting up a C++ project for a DLL in an IDE like Visual Studio.

Write the Code for a Borderless Window: You’ll use the Windows API to create a window. To make it borderless, you can modify the window style in the CreateWindowEx function.

Here is a simple example:

#include <windows.h>

// Function declaration
extern "C" __declspec(dllexport) void CreateBorderlessWindow();

// Window procedure
LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
    switch (uMsg) {
    case WM_DESTROY:
        PostQuitMessage(0);
        return 0;
    }
    return DefWindowProc(hwnd, uMsg, wParam, lParam);
}

// Create a borderless window
void CreateBorderlessWindow() {
    const char CLASS_NAME[] = "BorderlessWindowClass";

    WNDCLASS wc = { };
    wc.lpfnWndProc = WindowProc;
    wc.hInstance = GetModuleHandle(NULL);
    wc.lpszClassName = CLASS_NAME;

    RegisterClass(&wc);

    HWND hwnd = CreateWindowEx(
        0,                              // Optional window styles.
        CLASS_NAME,                     // Window class
        "A Borderless Window",          // Window text
        WS_POPUP,                       // Window style - Borderless
        CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
        NULL,       // Parent window
        NULL,       // Menu
        wc.hInstance,  // Instance handle
        NULL        // Additional application data
    );

    if (hwnd == NULL)
        return;

    ShowWindow(hwnd, SW_SHOW);
    UpdateWindow(hwnd);

    MSG msg = { };
    while (GetMessage(&msg, NULL, 0, 0)) {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
}

Compile the DLL: After writing your code, compile the DLL.

Step 2: Call the DLL Function from VBA

Declare the External Function in VBA: In your VBA code, you need to declare the function from the DLL so that it can be called.
```
Declare PtrSafe Sub CreateBorderlessWindow Lib "YourDllPath.dll" ()
```

Call the Function: Use the declared function in your VBA code.

Sub ShowBorderlessWindow()
    CreateBorderlessWindow
End Sub

Step 3: Testing and Troubleshooting

Test the Integration: Run the VBA macro and check if the borderless window appears as expected.
Handle Errors: Make sure to add error handling in your VBA code to manage any issues with loading or executing the DLL.

Important Notes

DLL Path: Replace "YourDllPath.dll" with the actual path of your compiled DLL.
64-bit vs 32-bit: Ensure that your VBA environment and the compiled DLL are compatible (both 32-bit or both 64-bit).
Administrator Privileges: Depending on the settings, running such code might require administrator privileges.
Security Settings: Be aware of security settings in Excel that may prevent the running of macros or loading of DLLs.

This is a simplified example and might require adjustments based on your specific requirements and the environment in which you’re working.

To create a C++ DLL that opens a borderless window and automatically closes it after a specified period of time, you’ll need to modify the DLL code to include a timer. The timer will trigger an event after the specified time has elapsed, upon which the window will close and release its resources. Here’s how you can implement this:

Step 1: Modify the C++ DLL Code

Include a Timer: Use the SetTimer function to create a timer. When the timer elapses, you can handle the WM_TIMER message in your window procedure to close the window.

Sample C++ Code:

#include <windows.h>

// Function declaration
extern "C" __declspec(dllexport) void CreateBorderlessWindow(int milliseconds);

// Window procedure
LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
    switch (uMsg) {
    case WM_TIMER:
        DestroyWindow(hwnd);
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        return 0;
    default:
        return DefWindowProc(hwnd, uMsg, wParam, lParam);
    }
}

// Create a borderless window that closes after a specified time
void CreateBorderlessWindow(int milliseconds) {
    const char CLASS_NAME[] = "BorderlessWindowClass";

    WNDCLASS wc = { };
    wc.lpfnWndProc = WindowProc;
    wc.hInstance = GetModuleHandle(NULL);
    wc.lpszClassName = CLASS_NAME;

    RegisterClass(&wc);

    HWND hwnd = CreateWindowEx(
        0,                              // Optional window styles.
        CLASS_NAME,                     // Window class
        "A Borderless Window",          // Window text
        WS_POPUP,                       // Window style - Borderless
        CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
        NULL,       // Parent window
        NULL,       // Menu
        wc.hInstance,  // Instance handle
        NULL        // Additional application data
    );

    if (hwnd == NULL)
        return;

    // Set a timer to close the window
    SetTimer(hwnd, 1, milliseconds, NULL);

    ShowWindow(hwnd, SW_SHOW);
    UpdateWindow(hwnd);

    MSG msg = { };
    while (GetMessage(&msg, NULL, 0, 0)) {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
}

In this modified code, the CreateBorderlessWindow function now takes an additional parameter milliseconds, which specifies the duration after which the window should close.

Step 2: Call the Modified DLL Function from VBA

Declare the Modified Function in VBA:

Declare PtrSafe Sub CreateBorderlessWindow Lib "YourDllPath.dll" (ByVal milliseconds As Long)

Call the Function with a Time Duration:

Sub ShowBorderlessWindowForDuration()
    ' Open the window for 5000 milliseconds (5 seconds)
    CreateBorderlessWindow 5000
End Sub

Step 3: Compile and Test

Compile the DLL: Make sure to compile the modified DLL code.
Test: Run the VBA macro and observe if the window opens and then closes automatically after the specified duration.

Additional Notes

Timer Resolution: The Windows timer is not high-resolution, so the actual duration may vary slightly.
Testing in Different Environments: The behavior might differ slightly based on the system’s performance and load.
Error Handling: Ensure robust error handling in both the DLL and VBA code for production use.

The SetTimer function in the Windows API is used to create a timer that sends a WM_TIMER message to the specified window at regular intervals. It’s a mechanism that allows you to execute a piece of code at specified intervals. This is useful in a variety of applications, such as creating periodic updates in a UI or implementing time-limited actions.

Syntax of `SetTimer`

UINT_PTR SetTimer(
  HWND hWnd,
  UINT_PTR nIDEvent,
  UINT uElapse,
  TIMERPROC lpTimerFunc
);

hWnd: Handle to the window to be associated with the timer. This window will receive the WM_TIMER messages generated by the timer.
nIDEvent: Specifies a unique identifier for the timer.
uElapse: Specifies the time-out value, in milliseconds. This is the interval between successive WM_TIMER messages.
lpTimerFunc: Pointer to the function that will be notified when the timer elapses. If this parameter is NULL, the system posts a WM_TIMER message to the message queue of the window specified by hWnd.

How It Works

When you call SetTimer, the system creates a timer with the specified interval.
Once the timer interval elapses, the system posts a WM_TIMER message to the message queue of the specified window.
The window procedure of the specified window then handles the WM_TIMER message. In a typical use case, this would involve executing some periodic task.

Example Usage in C++

In the context of a C++ Windows application:

SetTimer(hwnd,            // Handle to the window
         1,               // Timer identifier
         1000,            // Interval in milliseconds (1 second)
         NULL);           // No timer callback function

In this example, a WM_TIMER message will be sent to the window with the handle hwnd every 1000 milliseconds (1 second). The window procedure of this window should then handle the WM_TIMER message, typically with a switch-case statement in the message loop.

Closing the Timer

To destroy the timer, you use the KillTimer function:

KillTimer(hwnd, 1);  // hwnd is the window handle, 1 is the timer identifier

This is important to ensure that resources are released and the timer is properly terminated, especially when closing the window or exiting the application.

Displaying rapidly changing image sequences on a borderless window created by a C++ DLL, which is invoked from VBA, involves several key steps. You’ll need to modify the C++ DLL to handle image loading and rendering, and to update the window with new images at a specified rate. Here’s an outline of how you can implement this:

Step 1: Modify C++ DLL for Image Display

Image Handling: Use a graphics library that is suitable for loading and displaying images. For Windows applications, GDI+ is a commonly used library. You’ll need to include the GDI+ headers and link against its library.
Load and Display Images: Modify the window procedure to handle image loading and rendering. You might need to create an off-screen buffer to render the images before displaying them on the window.
Timed Image Updates: Use a timer (like with SetTimer) to regularly update the images. Each time the timer elapses, load the next image in the sequence and render it to the window.

Sample Code Snippet:

This is a simplified example. In a real-world application, you would need more robust image handling and resource management.

// Include GDI+ headers
#include <windows.h>
#include <gdiplus.h>
using namespace Gdiplus;

// Initialization and cleanup for GDI+
ULONG_PTR gdiplusToken;
GdiplusStartupInput gdiplusStartupInput;
GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL);

// ... [Rest of the code, including window creation and timer setup]

// Window procedure
LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
    switch (uMsg) {
    case WM_TIMER:
        // Load and display next image
        // ...
        InvalidateRect(hwnd, NULL, FALSE); // Trigger WM_PAINT for redraw
        break;
    case WM_PAINT:
        {
            PAINTSTRUCT ps;
            HDC hdc = BeginPaint(hwnd, &ps);

            // Render the image using GDI+
            Graphics graphics(hdc);
            // Assuming 'image' is a Gdiplus::Image object loaded elsewhere
            graphics.DrawImage(image, 0, 0, image->GetWidth(), image->GetHeight());

            EndPaint(hwnd, &ps);
        }
        break;
    // ... [Rest of the window procedure]
    }
}

// Cleanup GDI+
GdiplusShutdown(gdiplusToken);

Step 2: Call the Modified DLL Function from VBA

Invoke the Function: Similar to the previous example, use VBA to call the function in the DLL. The modification would mostly be in the DLL, not in the VBA part.

Step 3: Compiling and Testing

Compile the DLL: Make sure to compile the modified DLL code with GDI+ support.
Testing: Run the VBA macro and check if the images are displayed and updated as expected.

Additional Notes

Image Sequences: Managing the sequence of images (like loading them from files) and ensuring smooth transitions is a complex task and might require careful handling of timing and resources.
Performance: Rendering images, especially at high rates, can be resource-intensive. Make sure to optimize your image handling and rendering code for performance.
GDI+ Initialization: Don’t forget to initialize and shut down GDI+ properly in your application.
Memory Management: Ensure proper management of memory and resources, especially when dealing with graphics.

This overview provides a basic framework. Implementing a fully functional system with smooth image rendering will require a deeper dive into graphics programming and resource management.

Creating a complete C++ DLL that combines both the window pop-up and the image loading from an array of bytes involves several steps. In this example, I’ll use GDI+ for image rendering. Please note that this is a simplified example for educational purposes. Real-world applications may require more robust error checking and resource management.

Full C++ Code Example

#include <windows.h>
#include <gdiplus.h>
#include <string>

using namespace Gdiplus;

ULONG_PTR gdiplusToken;

// Function declaration
extern "C" __declspec(dllexport) void CreateBorderlessWindowWithImage(BYTE* imageBytes, int length);

// Window procedure
LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
    static Gdiplus::Bitmap* image = nullptr;

    switch (uMsg) {
    case WM_CREATE:
        {
            CREATESTRUCT* pCreate = reinterpret_cast<CREATESTRUCT*>(lParam);
            BYTE* data = reinterpret_cast<BYTE*>(pCreate->lpCreateParams);
            image = Gdiplus::Bitmap::FromStream(SHCreateMemStream(data, length));
            if (!image || image->GetLastStatus() != Gdiplus::Ok) {
                MessageBox(hwnd, "Failed to load image", "Error", MB_ICONERROR);
                PostQuitMessage(0);
            }
        }
        break;
    case WM_PAINT:
        {
            PAINTSTRUCT ps;
            HDC hdc = BeginPaint(hwnd, &ps);
            Graphics graphics(hdc);

            if (image) {
                graphics.DrawImage(image, 0, 0, image->GetWidth(), image->GetHeight());
            }

            EndPaint(hwnd, &ps);
        }
        break;
    case WM_DESTROY:
        if (image) {
            delete image;
            image = nullptr;
        }
        PostQuitMessage(0);
        break;
    default:
        return DefWindowProc(hwnd, uMsg, wParam, lParam);
    }
    return 0;
}

// Create a borderless window with an image
void CreateBorderlessWindowWithImage(BYTE* imageBytes, int length) {
    Gdiplus::GdiplusStartupInput gdiplusStartupInput;
    GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL);

    const char CLASS_NAME[] = "BorderlessWindowClass";

    WNDCLASS wc = { };
    wc.lpfnWndProc = WindowProc;
    wc.hInstance = GetModuleHandle(NULL);
    wc.lpszClassName = CLASS_NAME;

    RegisterClass(&wc);

    HWND hwnd = CreateWindowEx(
        0,                              // Optional window styles.
        CLASS_NAME,                     // Window class
        "A Borderless Window",          // Window text
        WS_POPUP,                       // Window style - Borderless
        CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
        NULL,       // Parent window
        NULL,       // Menu
        wc.hInstance,  // Instance handle
        imageBytes   // Additional data (image bytes)
    );

    if (hwnd == NULL) {
        GdiplusShutdown(gdiplusToken);
        return;
    }

    ShowWindow(hwnd, SW_SHOW);
    UpdateWindow(hwnd);

    MSG msg = { };
    while (GetMessage(&msg, NULL, 0, 0)) {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    GdiplusShutdown(gdiplusToken);
}

Explanation

Image Loading: The image is loaded from an array of bytes passed to the CreateBorderlessWindowWithImage function. This array is treated as a stream from which GDI+ creates a Bitmap.
Window Creation: A borderless window is created, and the image is displayed in this window.
Window Procedure: The WM_PAINT message is used to draw the image on the window. The WM_DESTROY message ensures that resources are released properly.
GDI+ Initialization and Shutdown: GDI+ is initialized at the beginning of the CreateBorderlessWindowWithImage function and shut down before exiting the function.

Compilation and Usage Notes

GDI+ Library: When compiling this code, ensure that you link against the GDI+ library (gdiplus.lib).
Array of Bytes: The imageBytes parameter should be a pointer to an array of bytes that represents an image in a format that GDI+ can decode (like BMP, JPEG, PNG).
Error Handling: In a production environment, you should include robust error handling, especially for operations like loading the image and creating the window.
Memory Streams: SHCreateMemStream is used to create an IStream from a memory buffer. This function is part of the Windows API.

This code provides a basic framework for displaying an image in a borderless window using a C++

Creating a C++ DLL to display images in a borderless window is a complex task, especially when aiming for cross-platform compatibility. However, since Windows-specific APIs (like GDI+ and window creation functions) are inherently Windows-centric, achieving full cross-platform compatibility is not feasible. Nevertheless, I’ll provide a more detailed and explanatory version of the code, focusing on Windows but with thorough comments for educational purposes.

Detailed C++ Code Example

#include <windows.h>
#include <gdiplus.h>
#include <iostream>

// Use the Gdiplus namespace to simplify code
using namespace Gdiplus;

// Global token for GDI+ usage
ULONG_PTR gdiplusToken;

// Function declaration for creating a window with an image
extern "C" __declspec(dllexport) void CreateBorderlessWindowWithImage(BYTE* imageBytes, UINT length);

// Window procedure function
LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
    static Bitmap* image = nullptr;  // Static pointer to hold the image

    switch (uMsg) {
    case WM_CREATE:
        {
            // This block handles window creation.
            // The image data is passed as a parameter in WM_CREATE.
            CREATESTRUCT* pCreate = reinterpret_cast<CREATESTRUCT*>(lParam);
            BYTE* data = reinterpret_cast<BYTE*>(pCreate->lpCreateParams);

            // Create an IStream from the byte array (image data)
            HGLOBAL hMem = GlobalAlloc(GMEM_MOVEABLE, length);
            void* pMem = GlobalLock(hMem);
            memcpy(pMem, data, length);
            IStream* pStream = nullptr;
            CreateStreamOnHGlobal(hMem, TRUE, &pStream);

            // Load the image from the stream
            image = new Bitmap(pStream);
            pStream->Release();

            if (!image || image->GetLastStatus() != Gdiplus::Ok) {
                MessageBox(hwnd, L"Failed to load image", L"Error", MB_ICONERROR);
                PostQuitMessage(0);
            }
        }
        break;
    case WM_PAINT:
        {
            // This block handles the paint messages for the window.
            PAINTSTRUCT ps;
            HDC hdc = BeginPaint(hwnd, &ps);
            Graphics graphics(hdc);

            // Draw the image
            if (image) {
                graphics.DrawImage(image, 0, 0, image->GetWidth(), image->GetHeight());
            }

            EndPaint(hwnd, &ps);
        }
        break;
    case WM_DESTROY:
        {
            // This block handles the cleanup when the window is destroyed.
            if (image) {
                delete image;
                image = nullptr;
            }
            PostQuitMessage(0);
        }
        break;
    default:
        return DefWindowProc(hwnd, uMsg, wParam, lParam);
    }
    return 0;
}

// Function to create the borderless window and display the image
void CreateBorderlessWindowWithImage(BYTE* imageBytes, UINT length) {
    // Initialize GDI+
    GdiplusStartupInput gdiplusStartupInput;
    GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL);

    // Define the class name for the window
    const char CLASS_NAME[] = "BorderlessWindowClass";

    // Fill in the WNDCLASS struct to define the window
    WNDCLASS wc = { };
    wc.lpfnWndProc = WindowProc;  // Pointer to the window procedure
    wc.hInstance = GetModuleHandle(NULL);
    wc.lpszClassName = CLASS_NAME;

    // Register the window class
    RegisterClass(&wc);

    // Create the window
    HWND hwnd = CreateWindowEx(
        0,                              // Optional window styles.
        CLASS_NAME,                     // Window class
        "A Borderless Window",          // Window text
        WS_POPUP,                       // Window style - Borderless
        CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
        NULL,       // Parent window
        NULL,       // Menu
        wc.hInstance,  // Instance handle
        imageBytes   // Pass image bytes to WM_CREATE
    );

    // Check if window creation was successful
    if (hwnd == NULL) {
        GdiplusShutdown(gdiplusToken);
        return;
    }

    // Show and update the window
    ShowWindow(hwnd, SW_SHOW);
    UpdateWindow(hwnd);

    // Message loop
    MSG msg = { };
    while (GetMessage(&msg, NULL, 0, 0)) {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    // Shutdown GDI+ on exit
    GdiplusShutdown(gdiplusToken);
}

Explanation

GDI+ Initialization: GDI+ is initialized before creating the window. This is necessary for image rendering.
Window Procedure (WindowProc): This function handles various messages sent to the window. Key points include:
- WM_CREATE: Handles the creation of the window. Here, the image is loaded from the byte array passed to the window.
- WM_PAINT: Invoked when the window needs to be redrawn. This is where the image is rendered.
- WM_DESTROY: Handles cleanup, ensuring the image is deleted and resources are released when the window is closed.
Creating the Window: The window is created with CreateWindowEx using a borderless style (WS_POPUP).
Message Loop: After the window is created, a message loop runs, handling messages sent to the window.
GDI+ Shutdown: It’s crucial to shut down GDI+ after the message loop exits to release resources.

Compilation and Integration

Link Against GDI+: When compiling, ensure the code is linked against the GDI+ library (gdiplus.lib).
Passing Image Data: The image data should be passed as a byte array. This array represents the image in a format that GDI+ can decode (e.g., BMP, JPEG, PNG).
Error Handling: Include robust error handling for real-world applications.

This code serves as an educational example and may need adjustments for specific use cases, especially in terms of error handling and resource management.

To create a borderless window at the specific screen coordinates obtained from an Excel cell, you’ll need to modify the C++ DLL function to accept the coordinates as parameters and then position the window accordingly. Here’s how you can update the C++ code to achieve this:

Step 1: Modify the C++ DLL Function

Update the CreateBorderlessWindowWithImage function to accept additional parameters for the X and Y screen coordinates. Use these coordinates to position the window when calling CreateWindowEx.

// Updated function declaration
extern "C" __declspec(dllexport) void CreateBorderlessWindowWithImage(BYTE* imageBytes, UINT length, int posX, int posY);

// ... [Rest of the existing code]

// Updated function definition
void CreateBorderlessWindowWithImage(BYTE* imageBytes, UINT length, int posX, int posY) {
    // ... [GDI+ initialization and other setup]

    // Updated window creation with specified position
    HWND hwnd = CreateWindowEx(
        0,                              // Optional window styles.
        CLASS_NAME,                     // Window class
        "A Borderless Window",          // Window text
        WS_POPUP,                       // Window style - Borderless
        posX, posY, 300, 200,           // Position and size (300x200 window size for example)
        NULL,       // Parent window
        NULL,       // Menu
        wc.hInstance,  // Instance handle
        imageBytes   // Pass image bytes to WM_CREATE
    );

    // ... [Rest of the existing code]
}

Step 2: Call the Updated DLL Function from VBA

Pass the screen coordinates (obtained earlier from the Excel cell position) to the updated DLL function.

' Updated VBA declaration
Declare PtrSafe Sub CreateBorderlessWindowWithImage Lib "YourDllPath.dll" _
    (ByVal imageBytes As LongPtr, ByVal length As Long, ByVal posX As Long, ByVal posY As Long)

' Example VBA function to call the DLL
Sub ShowImageAtCellPosition()
    Dim imageBytes() As Byte ' Load or define your image data here
    Dim length As Long
    length = UBound(imageBytes) - LBound(imageBytes) + 1

    ' Example screen coordinates
    Dim posX As Long, posY As Long
    posX = 100 ' Replace with actual X coordinate from Excel cell
    posY = 100 ' Replace with actual Y coordinate from Excel cell

    ' Call the DLL function
    CreateBorderlessWindowWithImage VarPtr(imageBytes(0)), length, posX, posY
End Sub

Explanation

The C++ DLL function now takes two additional parameters posX and posY, which are used to set the window’s screen position.
In the VBA code, you call this function with the screen coordinates obtained from the Excel cell.
Make sure the image data is correctly loaded into the imageBytes array in VBA before calling the function.

Additional Considerations

Image Data: Ensure that the image data is correctly formatted and loaded into the imageBytes array in VBA.
Error Handling: Implement proper error handling in both C++ and VBA codes, especially when dealing with external resources and memory allocation.
Window Size: In this example, the window size is set to 300x200 pixels. You might want to adjust this based on the size of the image or other requirements.

This approach should position the window precisely at the screen coordinates corresponding to an Excel cell, displaying the image in that location.

Passing arrays from VBA to a C++ DLL is not quite as straightforward as directly passing a pointer to the array. VBA arrays are managed by the VBA runtime and their memory layout might not be directly compatible with what a C++ DLL expects. However, you can pass array data from VBA to C++, but it typically requires some careful handling. Here are the general steps:

Step 1: Prepare the Array in VBA

Create a SafeArray: In VBA, create a SafeArray. This is a data structure used by COM (Component Object Model) that can be more safely passed between different languages and environments.
Fill the Array: Populate the array with the data you want to pass to the C++ DLL.

Step 2: Pass the Array to C++ DLL

Declare the DLL Function in VBA: When declaring the function in VBA, specify the array parameter as either ByRef for a single-dimension array or ByVal as Variant for multi-dimensional arrays.
C++ DLL Function Signature: On the C++ side, receive the array as a pointer to the base type (for single-dimension arrays) or as a SAFEARRAY (for multi-dimensional arrays).
Access the Array in C++: In the C++ DLL, you’ll need to lock the SafeArray to access its data safely. Use SafeArrayAccessData and SafeArrayUnaccessData.

Example

VBA Code

Declare PtrSafe Sub ProcessArray Lib "YourDllPath.dll" (ByRef arrData As Byte, ByVal length As Long)

Sub ExampleCall()
    Dim byteArray() As Byte
    ReDim byteArray(0 To 9) As Byte

    ' Fill the array with data
    Dim i As Integer
    For i = LBound(byteArray) To UBound(byteArray)
        byteArray(i) = i
    Next i

    ' Call the DLL function
    ProcessArray byteArray(0), UBound(byteArray) - LBound(byteArray) + 1
End Sub

C++ Code

extern "C" __declspec(dllexport) void ProcessArray(BYTE* arrData, int length) {
    // Process the array
    for (int i = 0; i < length; ++i) {
        // Example processing
        std::cout << "Array Element [" << i << "]: " << static_cast<int>(arrData[i]) << std::endl;
    }
}

Important Notes

Data Types: Ensure that the data types in VBA and C++ match. For example, a VBA Byte array should be received as a BYTE* in C++.
Memory Management: Be cautious with memory management. The VBA runtime manages the memory for the array, so you shouldn’t attempt to free or reallocate it in the C++ code.
Error Handling: Implement proper error handling, especially when dealing with external DLL calls.
Array Bounds: Be sure to pass the array bounds to the DLL if necessary, as C++ won’t inherently know the size of the array it receives.

This method allows for the passing of array data from VBA to a C++ DLL, but it’s important to ensure that both sides agree on the format and layout of the data.

Passing a multi-dimensional array (like the values of an Excel range) from VBA to a C++ DLL requires handling the array as a Variant in VBA and as a SAFEARRAY in the C++ DLL. Here’s an example:

VBA Code

In VBA, you declare the DLL function to accept a Variant and pass the array as such. For example, if you’re passing the values of an Excel range:

' Declare the DLL function
Declare PtrSafe Sub ProcessVariantArray Lib "YourDllPath.dll" (ByVal arr As Variant)

Sub ExampleCall()
    Dim rng As Range
    Set rng = ThisWorkbook.Sheets("Sheet1").Range("A1:C3") ' Example range

    ' Call the DLL function with the range values
    ProcessVariantArray rng.Value
End Sub

C++ Code

In C++, you need to handle the array as a SAFEARRAY. The function signature receives a VARIANT, which you then convert to a SAFEARRAY*.

#include <windows.h>
#include <iostream>

extern "C" __declspec(dllexport) void ProcessVariantArray(VARIANT* arr) {
    // Check if we received an array
    if (arr && (arr->vt & VT_ARRAY) && (arr->vt & VT_VARIANT)) {
        // Access the SafeArray
        SAFEARRAY* pSafeArray = V_ARRAY(arr);
        long lowerBound, upperBound;

        // Get the bounds of the first dimension
        SafeArrayGetLBound(pSafeArray, 1, &lowerBound);
        SafeArrayGetUBound(pSafeArray, 1, &upperBound);

        VARIANT varElement;
        for (long i = lowerBound; i <= upperBound; i++) {
            // Access each element
            SafeArrayGetElement(pSafeArray, &i, &varElement);

            // Process the element (example: print it)
            if (varElement.vt == VT_BSTR) {
                std::wcout << L"Element [" << i << L"]: " << varElement.bstrVal << std::endl;
            }

            VariantClear(&varElement);
        }
    }
}

Explanation

VBA: The Excel range’s values are passed as a Variant. This can handle a multi-dimensional array.
C++: The Variant is treated as a SAFEARRAY. The code iterates through the array and accesses each element. Note that Excel ranges typically come in as 2D arrays, even for a single row or column.

Important Notes

Data Type Handling: The example assumes the array contains BSTR (string) elements. If your array contains different data types (like numbers), you’ll need to modify the C++ code to handle these types.
SafeArray Dimension: This example handles a single dimension for simplicity. Excel ranges are usually 2D arrays (even if they are a single row or column), so for a complete implementation, you’d need to handle both dimensions.
Error Checking: The C++ code should include robust error checking and handling. Make sure to check the SAFEARRAY’s dimensions and types before accessing its elements.

This example gives a basic idea of how to pass a multi-dimensional Variant array from VBA to a C++ DLL, but for practical use, especially with different types of data and error conditions, more comprehensive handling would be necessary.

Yes, if you know the specific type of the elements within the Variant array in advance, you can optimize the C++ code by skipping certain checks and directly accessing the data in its native format. This can lead to performance improvements, especially for large arrays or in scenarios where the function is called frequently.

Optimized C++ Code for Known Variant Type

Assuming the Variant array contains only doubles (a common scenario when dealing with numerical data from Excel), you can optimize the code as follows:

#include <windows.h>
#include <iostream>

extern "C" __declspec(dllexport) void ProcessDoubleArray(VARIANT* arr) {
    if (arr && (arr->vt == (VT_ARRAY | VT_VARIANT))) {
        SAFEARRAY* pSafeArray = V_ARRAY(arr);
        long lowerBound, upperBound;

        // Assuming a 1D array of doubles
        SafeArrayGetLBound(pSafeArray, 1, &lowerBound);
        SafeArrayGetUBound(pSafeArray, 1, &upperBound);

        // Directly access the double values
        for (long i = lowerBound; i <= upperBound; i++) {
            VARIANT varElement;
            SafeArrayGetElement(pSafeArray, &i, &varElement);

            if (varElement.vt == VT_R8) { // Check if the element is a double
                double value = varElement.dblVal;
                std::cout << "Element [" << i << "]: " << value << std::endl;
            }

            VariantClear(&varElement);
        }
    }
}

Explanation

Type-Specific Access: The code directly accesses the elements as double values (VT_R8), avoiding the overhead of type checking for each element.
Variant Clearing: It is still important to clear the VARIANT after each use to avoid memory leaks, especially because SafeArrayGetElement copies the data.

VBA Side

On the VBA side, ensure that the data being passed is indeed an array of doubles to match the expectations of the C++ code:

' VBA code to call the DLL
Declare PtrSafe Sub ProcessDoubleArray Lib "YourDllPath.dll" (ByVal arr As Variant)

Sub ExampleCall()
    Dim rng As Range
    Set rng = ThisWorkbook.Sheets("Sheet1").Range("A1:C3") ' Example range

    ' Ensure that the range values are being passed as doubles
    ProcessDoubleArray rng.Value2
End Sub

Considerations

Data Type Consistency: This approach assumes that all elements in the array are of the same type (doubles in this case). If the array contains mixed types, this method will not work correctly.
Error Checking: While certain checks are skipped for performance, basic error handling should still be in place to handle unexpected scenarios.
Array Dimensions: The example assumes a 1D array. If dealing with a 2D array (more common with Excel ranges), you’ll need to adjust the code to iterate over both dimensions.

Yes, both VARIANT and SAFEARRAY are part of the Windows API, specifically within the context of COM (Component Object Model). COM is a Microsoft platform for software componentry, introduced by Microsoft in 1993, and is used extensively in Windows.

VARIANT

Definition: A VARIANT is a struct used in COM and OLE Automation that can store different types of data. It’s a key part of handling dynamic types and is heavily used in languages like VBA (Visual Basic for Applications) and scripting languages that interact with COM objects.
Usage: It’s designed to be a general-purpose data type, and it can store various data types including integers, floating-point numbers, strings, arrays (as SAFEARRAY), and more.

SAFEARRAY

Definition: A SAFEARRAY is a struct that encapsulates an array in a way that is safe for use in COM across different programming languages. It contains information about the number of dimensions, size of each dimension, and the data of the array itself.
Usage: It is used for passing arrays between COM components, and it ensures that the array data is managed correctly, taking into account different memory layouts and conventions used by various languages.

Integration with Windows API

These structures are part of the OLE Automation libraries (oleaut32.dll) which are a standard component of Windows.
The Windows API provides functions to manipulate VARIANT and SAFEARRAY structures, such as VariantInit, VariantClear, SafeArrayCreate, SafeArrayDestroy, SafeArrayGetElement, and more.
They are essential for applications that use COM interfaces, particularly when interfacing with scripting languages or automation clients like VBA.

Usage in C++ and VBA

In C++, you typically include <Windows.h> and <OleAuto.h> to work with VARIANT and SAFEARRAY.
In VBA (and other COM-based environments), these types are built-in and managed by the runtime, facilitating the interaction with COM objects and API functions that expect these types.

Their design allows for a relatively seamless exchange of data between different languages and environments in the Windows ecosystem, making them crucial for applications that extend or automate Microsoft Office products and other COM-based applications.

You’re right, and I appreciate your attention to detail. The usage of VarPtr() and LongPtr in the context of calling a C++ DLL from VBA is an important aspect to discuss, especially when dealing with pointers and memory addresses in a 64-bit environment.

VarPtr()

Purpose: VarPtr() is a function in VBA that returns the memory address of a variable. It’s often used when you need to pass the address of a variable to an API function or a DLL that expects a pointer.
Usage: This is particularly relevant when dealing with arrays or structures that need to be passed by reference to external functions.

LongPtr

Purpose: LongPtr is a data type in VBA introduced to handle pointer and handle values safely in a 64-bit environment. In 32-bit VBA, Long is used for pointers, but in 64-bit VBA, Long is not sufficient to store the larger memory addresses, so LongPtr is used instead.
Usage: It’s a conditional compilation type that resolves to Long in 32-bit VBA and to LongLong in 64-bit VBA, ensuring compatibility across different versions of Office.

Applying VarPtr() and LongPtr in VBA to DLL Calls

When you’re passing an array or a complex data type to a DLL function, you might use VarPtr() to get the address of the data. In the case of a 64-bit VBA environment, this address would be stored in a LongPtr variable.

Example of using VarPtr() and LongPtr:

Declare PtrSafe Sub ProcessArray Lib "YourDllPath.dll" (ByVal arrPtr As LongPtr)

Sub ExampleCall()
    Dim byteArray() As Byte
    ' ... Initialize the byteArray ...

    Dim arrAddress As LongPtr
    arrAddress = VarPtr(byteArray(0))

    ProcessArray arrAddress
End Sub

In this example, VarPtr(byteArray(0)) retrieves the address of the first element of byteArray, and LongPtr is used to store this address correctly in a 64-bit environment.

Considerations

Safety: Directly working with pointers and memory addresses can be risky, as it bypasses VBA’s memory management. It should be done with caution and an understanding of the implications.
64-bit Compatibility: Always use LongPtr instead of Long when dealing with addresses or handles to ensure compatibility with both 32-bit and 64-bit environments.
API and DLL Integration: This approach is often necessary when interfacing with Windows API functions or custom DLLs that require pointers to data structures or arrays.

Understanding how to correctly use these functions and types is crucial for successfully integrating VBA with external DLLs, especially in a 64-bit context.

Absolutely, let’s connect the dots between our previous discussions on getting window sizes, Excel cell coordinates, and the use of VarPtr() and LongPtr in VBA when interfacing with C++ DLLs. Here’s a comprehensive overview integrating these concepts:

1. Getting Excel Cell Coordinates in Pixels

From our earlier discussion, we established a method in VBA to obtain the screen pixel coordinates of a specific cell in an Excel worksheet. This involved:

Calculating the cell’s position within Excel using the Top and Left properties of the Range object.
Determining the position and size of the Excel application window using Windows API calls.
Adjusting for window decorations, ribbons, and toolbars.
Converting these measurements from points to pixels, considering the DPI scaling.

2. Using VBA to Call a C++ DLL

The goal was to create a borderless window at the specific screen coordinates obtained from an Excel cell using a C++ DLL. To achieve this:

The C++ DLL function was designed to accept screen coordinates (X and Y positions).
The VBA script then calls this DLL function, passing the calculated pixel coordinates of the Excel cell.

3. Integrating VarPtr() and LongPtr

When passing data from VBA to a C++ DLL, particularly pointers or arrays, VarPtr() and LongPtr are used:

VarPtr() provides the memory address of a variable, necessary when the DLL expects a pointer.
LongPtr ensures compatibility with both 32-bit and 64-bit environments by safely storing memory addresses or pointers.

Example Workflow

VBA Script to Calculate Cell Coordinates:

' Calculate cell coordinates in pixels
Dim cellLeft As Long, cellTop As Long
' ... Code to calculate cellLeft and cellTop ...

Prepare Data for DLL Call:

' If needed, use VarPtr to get the address of data
Dim ptrCellLeft As LongPtr, ptrCellTop As LongPtr
ptrCellLeft = VarPtr(cellLeft)
ptrCellTop = VarPtr(cellTop)

' Alternatively, directly pass cellLeft and cellTop if the DLL function expects values

Declare and Call DLL Function in VBA:

' Declare the DLL function
Declare PtrSafe Sub CreateWindowAtPosition Lib "YourDllPath.dll" (ByVal x As Long, ByVal y As Long)

' Call the DLL function with the coordinates
CreateWindowAtPosition cellLeft, cellTop

C++ DLL Function:

// Function in the DLL to create a window at a specified position
extern "C" __declspec(dllexport) void CreateWindowAtPosition(int x, int y) {
    // Code to create a borderless window at (x, y)
}

Final Considerations

Ensure that the data types and memory management strategies are consistent and safe across both VBA and C++.
Perform thorough testing, especially when working with screen coordinates and external DLL calls, to account for variations in screen setups and Excel versions.
Remember to include error handling in both VBA and C++ for robustness.

This integrated approach allows you to precisely position a window based on coordinates obtained from Excel, leveraging the capabilities of both VBA and C++.

Getting window size and position on macOS using system .dylib libraries typically involves using the Core Graphics framework and possibly other parts of the macOS APIs. Here’s a general approach using Objective-C or C, which you can adapt to your specific needs:

1. Access the Core Graphics Framework

The Core Graphics framework (CoreGraphics.framework) provides functions for interacting with the graphics system, including window management. You’ll need to include the relevant headers:

#include <CoreGraphics/CoreGraphics.h>

2. Getting Window Information

To get information about windows, including their size and position, you can use the Core Graphics function CGWindowListCopyWindowInfo. This function provides a list of dictionaries, each containing information about a window.

3. Example Code in C/Objective-C

Here’s an example of how you might use this in C or Objective-C:

#include <CoreFoundation/CoreFoundation.h>
#include <CoreGraphics/CoreGraphics.h>

int main() {
    // Get the list of all windows
    CFArrayRef windowList = CGWindowListCopyWindowInfo(kCGWindowListOptionOnScreenOnly, kCGNullWindowID);

    // Iterate through the window list
    for (CFIndex i = 0; i < CFArrayGetCount(windowList); i++) {
        // Get information for each window
        CFDictionaryRef windowInfo = CFArrayGetValueAtIndex(windowList, i);

        // Extract window ID, position, and size
        CFNumberRef windowID;
        CGRect windowBounds;
        if (CFDictionaryGetValueIfPresent(windowInfo, kCGWindowNumber, (const void**)&windowID) &&
            CFDictionaryGetValueIfPresent(windowInfo, kCGWindowBounds, (const void**)&windowBounds)) {

            printf("Window ID: %d\n", CFNumberGetIntValue(windowID));
            printf("Position: (%f, %f)\n", windowBounds.origin.x, windowBounds.origin.y);
            printf("Size: (%f, %f)\n", windowBounds.size.width, windowBounds.size.height);
        }
    }

    // Release the window list
    CFRelease(windowList);

    return 0;
}

4. Compilation and Usage

To compile this code, you need to have Xcode installed or use a compiler that can handle Objective-C and link against the Core Graphics framework.
This code should be run in an environment where you have permissions to access window information (e.g., running as a user application, not a sandboxed app).

Notes

Privacy and Security: Recent versions of macOS have privacy and security features that may restrict access to certain information about other applications’ windows.
Window Information: The information returned will include details for all on-screen windows. You may need to filter or process this data to find the specific window you’re interested in.
API Changes: Keep in mind that Apple periodically updates its APIs, so you should consult the latest documentation for Core Graphics to ensure compatibility.

This code provides a basic framework to get you started. Depending on your specific use case, you might need to delve deeper into the macOS APIs and possibly handle additional edge cases or permissions.

Calling native macOS APIs, like those from the Core Graphics framework, directly from Excel to get the size and position of the Excel application window is not straightforward. Excel for Mac primarily uses VBA (Visual Basic for Applications) for automation and scripting, which doesn’t natively support calling macOS system libraries.

However, you can work around this limitation by creating a separate program or script in a language that can interact with macOS system libraries (like C, C++, or Objective-C) and then invoking this external program from Excel VBA. Here’s a high-level approach:

1. Create a macOS Application or Script

Develop a small macOS application or script in C, C++, or Objective-C using the Core Graphics framework to get the window size and position. This application will retrieve the information and then output it in a format that can be read by your VBA script (e.g., writing to a file or standard output).

2. Call the External Program from Excel VBA

Use VBA to call the external macOS application or script. You can use the Shell function in VBA to execute the program and capture its output.

Example Workflow

Step 1: macOS Application/Script

Develop a program in Objective-C (as described in the previous message) that outputs the size and position of the Excel window. You might need to filter the window list to find the Excel application window specifically, possibly by window name or process ID.

Step 2: VBA Script to Call the macOS Program

In your Excel VBA script:

Sub GetExcelWindowSizeAndPosition()
    Dim scriptPath As String
    scriptPath = "/path/to/your/macos/application"  ' Path to your macOS app or script

    Dim output As String
    output = Shell(scriptPath, vbNormalFocus)  ' Execute the script and get output

    ' Process the output to read the window size and position
    ' ...
End Sub

Considerations

Execution Permissions: Ensure the external program or script has the necessary permissions to be executed and to access window information.
Output Parsing: You’ll need to parse the output of the script appropriately in your VBA code.
Excel Identification: The external script should correctly identify the Excel application window among all open windows.
Security and Privacy: Be aware of macOS privacy and security settings that may restrict access to window information.

This approach requires a fair amount of interoperation between VBA and a macOS-specific program and is relatively advanced. Depending on your use case and environment, you may need to adjust permissions, handle different versions of macOS, or consider alternative approaches like AppleScript or Automator workflows.

Determining the window ID or name of the Excel application on macOS involves querying the system for information about open windows and their associated processes. You can achieve this using macOS programming APIs, but it requires some familiarity with macOS system programming and potentially a combination of Objective-C, C, or Swift code.

Here are the steps to identify the Excel application’s window ID or name:

1. Use macOS APIs to List Windows

Using the Core Graphics or Accessibility APIs, you can list all open windows on the system. This will give you access to window-related information like window IDs, names, and associated process IDs.

2. Filter for the Excel Application

You’ll need to filter this list to find windows belonging to the Excel application. This can be done by checking the process ID against Excel’s process ID or by matching the window name/title.

3. Obtain Excel Window ID or Name

Once you’ve identified the Excel windows, you can extract their window IDs and names.

Example Using Core Graphics API

Here’s a simplified example in C/Objective-C:

#include <CoreGraphics/CoreGraphics.h>

void printExcelWindowInfo() {
    // Get the list of windows
    CFArrayRef windowList = CGWindowListCopyWindowInfo(kCGWindowListOptionOnScreenOnly, kCGNullWindowID);

    // Iterate over the windows
    for (CFIndex i = 0; i < CFArrayGetCount(windowList); i++) {
        CFDictionaryRef windowInfo = CFArrayGetValueAtIndex(windowList, i);

        // Get window name and process name
        CFStringRef windowName;
        CFStringRef processName;
        if (CFDictionaryGetValueIfPresent(windowInfo, kCGWindowName, (const void**)&windowName) &&
            CFDictionaryGetValueIfPresent(windowInfo, kCGWindowOwnerName, (const void**)&processName)) {

            // Check if this is an Excel window
            if (CFStringCompare(processName, CFSTR("Microsoft Excel"), 0) == kCFCompareEqualTo) {
                // Get window ID
                CFNumberRef windowID;
                CFDictionaryGetValueIfPresent(windowInfo, kCGWindowNumber, (const void**)&windowID);

                // Print or process the information
                NSLog(@"Excel Window ID: %@, Name: %@", windowID, windowName);
            }
        }
    }

    CFRelease(windowList);
}

Calling from Excel

To call this from Excel, you would need to compile this code into an executable or a script, and then use Excel VBA to execute this script and parse its output. Since VBA doesn’t directly support macOS system calls, this workaround is necessary.

Considerations

Privacy Settings: Recent macOS versions have strict privacy settings that might restrict access to certain types of window information.
Accessibility API: Depending on the information you need and the macOS version, you might also explore using the Accessibility API, which can provide more detailed information about window content and controls.
Running External Code: If you’re not comfortable with macOS programming, or if it’s not feasible to run external code, an alternative might be to use AppleScript, which can interact with many macOS applications, including Excel, and might provide the necessary window information.

Yes, once you have the position and size of the Excel application window on macOS, you can calculate the screen space coordinates of a specific cell within the Excel window. However, this calculation requires a few additional steps:

Obtain the Position and Size of the Excel Window: Using the methods discussed earlier, find the top-left corner (x, y coordinates) and the dimensions (width and height) of the Excel window.
Determine Internal Offsets: Excel’s window includes elements like the title bar, menu, ribbon, and possibly other toolbars. You need to account for these to find the starting point of the actual spreadsheet grid.
Calculate the Cell’s Position within Excel: This involves determining the cell’s position relative to the starting point of the spreadsheet grid. Excel does not provide direct methods to get pixel coordinates of a cell, so this part can be tricky. You might have to estimate this based on known dimensions (like the default width/height of cells) or use accessibility features/APIs to get more precise measurements.
Combine the Information: Add the cell’s relative coordinates to the window’s screen coordinates to get the cell’s absolute position on the screen.

Example Calculation

Let’s assume you have the following information:

Excel window’s top-left corner is at (windowX, windowY).
The cell’s position relative to the start of the spreadsheet grid is (cellOffsetX, cellOffsetY).
The internal offsets for the window decorations and toolbars are (offsetX, offsetY).

Then the screen space coordinates of the cell would be:

Cell’s screen X-coordinate: windowX + offsetX + cellOffsetX
Cell’s screen Y-coordinate: windowY + offsetY + cellOffsetY

Limitations and Considerations

Estimation: Without direct API support to get a cell’s coordinates in Excel for Mac, you may need to rely on estimations or assumptions, which might not be 100% accurate.
Screen Scaling: Be aware of screen scaling factors, especially on Retina displays, as these can affect the calculation of pixel coordinates.
Dynamic Layouts: The size and position of toolbars, ribbons, and other UI elements in Excel can change, affecting the offsets. If these elements are customizable by the user or different across Excel versions, your calculation needs to account for these variations.
Accessibility APIs: Consider using macOS Accessibility APIs as they might provide more detailed and accurate information about UI elements and their positions.

This method requires a combination of system-level window information and application-specific layout details, making it somewhat complex and potentially prone to inaccuracies due to the estimation of internal offsets and cell dimensions.

macOS itself does not directly provide the internal offsets of application windows (like the title bar, menu bar, ribbons, and toolbars within Excel) through its standard APIs. These offsets are usually considered part of the internal layout of the application’s user interface, managed by the application itself rather than the operating system.

However, there are a few approaches you can consider to estimate or obtain these internal offsets:

1. Accessibility APIs

macOS’s Accessibility API is designed to provide information about the user interface elements of applications, primarily for assistive technologies. You might be able to use this API to get details about specific elements within the Excel window. For example:

AXUIElement: This is the principal element in the Accessibility API, representing UI elements of applications. You can query the positions and sizes of specific elements.
Scripting Bridge or AppleScript: For certain applications, AppleScript (or the Scripting Bridge in Objective-C) can be used to get more detailed information about window contents.

2. Manual Calculation

If you have a consistent layout in Excel or if you can standardize the layout (for instance, by setting a fixed ribbon size, and knowing the sizes of other elements), you can manually calculate the offsets. This approach, however, is prone to errors and might not work across different versions of Excel or with different user settings.

3. Estimation Based on Screen Shots

In a more experimental approach, you could analyze screen captures of the Excel window to determine the sizes of different UI elements. This would be complex and not necessarily reliable for dynamic UIs.

4. Third-party Tools or Libraries

There might be third-party tools or libraries designed for UI inspection that can provide more detailed information about window layouts. However, this introduces dependencies and potential compatibility issues.

Example: Using Accessibility API

Here’s a conceptual example of how you might use the Accessibility API in Swift or Objective-C:

import Cocoa

let options: NSDictionary = [kAXTrustedCheckOptionPrompt.takeRetainedValue() as String: true]
let accessibilityEnabled = AXIsProcessTrustedWithOptions(options)

if accessibilityEnabled {
    if let app = AXUIElementCreateApplication(PID) as? AXUIElement {
        var value: AnyObject?
        AXUIElementCopyAttributeValue(app, kAXWindowsAttribute as CFString, &value)

        if let windows = value as? [AXUIElement] {
            for window in windows {
                // Now, you can query the window element for its internal layout,
                // such as the size of the title bar, ribbon, etc.
            }
        }
    }
}

Considerations

Privacy and Security: Recent versions of macOS have privacy settings that may restrict access to certain types of information about other applications’ windows.
AXUIElement Permissions: To use AXUIElement and related functions, you need to ensure that your application has the necessary permissions to control the computer (found in System Preferences > Security & Privacy > Accessibility).
Complexity and Variability: The layout of application windows can be complex and change based on user settings and actions, which makes this approach challenging.

These methods can be complex and may require handling various edge cases, so they’re generally used in situations where accurate information about window layouts is absolutely necessary.

Using the AXUIElement API in C++ on macOS is a bit more involved compared to using it in Objective-C or Swift, as it’s part of the macOS Objective-C runtime. However, you can still access and use these APIs from C++ by linking against the appropriate frameworks and using Objective-C bridging headers. Here’s a basic outline of how you can approach it:

1. Set Up Your C++ Project

To use AXUIElement in a C++ project on macOS:

Link Against the Frameworks: Your project needs to link against the ApplicationServices framework, which includes the Accessibility API.
Bridging Header: You might need a bridging header file to include Objective-C headers in your C++ code.

2. Bridging Objective-C and C++

Create a bridging header file (e.g., Bridge.h) that includes the necessary Objective-C headers:

#ifdef __OBJC__
    #import <ApplicationServices/ApplicationServices.h>
#endif

In your C++ code, you can include this bridging header. This allows you to use Objective-C types and functions:

// Your C++ file
#include "Bridge.h"

// Now, you can use AXUIElement and related functions here

3. Use AXUIElement API

In your C++ code, you can now interact with the Accessibility API:

void GetWindowInformation() {
    // Obtain the application reference
    AXUIElementRef appRef = AXUIElementCreateApplication(PID); // Replace PID with the process ID of the target application

    // Get window reference, etc.
    CFArrayRef windowArray;
    AXError error = AXUIElementCopyAttributeValue(appRef, kAXWindowsAttribute, (CFTypeRef*)&windowArray);

    if (error == kAXErrorSuccess) {
        // Process the windows
        for (CFIndex i = 0; i < CFArrayGetCount(windowArray); i++) {
            AXUIElementRef windowRef = (AXUIElementRef)CFArrayGetValueAtIndex(windowArray, i);
            // Use windowRef as needed
        }
        CFRelease(windowArray);
    }

    CFRelease(appRef);
}

4. Compile with Objective-C++

When compiling this code, you’ll need to use the Objective-C++ compiler, which is typically done by naming your source files with a .mm extension instead of .cpp.

5. Permissions and Privacy Concerns

Ensure that your application has the necessary permissions to use the Accessibility API:

The app needs to be added to the list of apps allowed to control your computer under System Preferences > Security & Privacy > Privacy > Accessibility.
Recent macOS versions have increased security and privacy controls, so accessing UI elements of other applications might be restricted.

Considerations

Objective-C++: Combining C++ with Objective-C can be complex and might lead to some challenges, especially regarding memory management and exception handling.
AXUIElement Limitations: The information you can get and the actions you can perform using AXUIElement may be limited by the macOS version and user settings.
Error Handling: Include robust error handling to manage various edge cases and potential failures when accessing Accessibility features.

Using AXUIElement from C++ on macOS requires careful setup and an understanding of both Objective-C and C++ conventions. This approach is best suited for advanced use cases where direct interaction with the macOS Accessibility API is necessary.

Measuring the size of UI elements using AXUIElementRef in macOS involves querying attributes of the UI elements that represent their size and position. The Accessibility API provides various attributes like kAXSizeAttribute and kAXPositionAttribute which can be used to get this information.

Here’s a step-by-step guide on how to do it:

1. Get the UI Element Reference

First, you need a reference to the UI element (AXUIElementRef) whose size you want to measure. In your case, if you’re starting with a window reference obtained through AXUIElementCopyAttributeValue, you might want to further drill down to specific UI elements within the window.

2. Query Size and Position Attributes

Once you have the AXUIElementRef for the specific UI element, you can query its size and position:

Size: Use kAXSizeAttribute to get the element’s size.
Position: Use kAXPositionAttribute to get the element’s position on the screen.

3. Example Code

Here’s an example of how you might query the size of a window in C++ using the Accessibility API:

#include <ApplicationServices/ApplicationServices.h>

// Function to get the size of a UI element
CGSize GetSizeOfUIElement(AXUIElementRef element) {
    CGSize size = {0, 0};

    if (element) {
        CFTypeRef sizeValue;
        AXError error = AXUIElementCopyAttributeValue(element, kAXSizeAttribute, &sizeValue);

        if (error == kAXErrorSuccess) {
            AXValueGetValue((AXValueRef)sizeValue, kAXValueCGSizeType, &size);
            CFRelease(sizeValue);
        }
    }

    return size;
}

// Example usage
void Example() {
    // Assuming you have a windowRef to a specific window
    AXUIElementRef windowRef; // Obtain this reference from the window list
    // ...

    CGSize windowSize = GetSizeOfUIElement(windowRef);
    std::cout << "Window Size: " << windowSize.width << "x" << windowSize.height << std::endl;

    // Don't forget to release windowRef when you're done
    CFRelease(windowRef);
}

Notes

Accessing Child Elements: If you need to measure specific elements within a window (like a toolbar), you’ll first need to obtain references to these child elements. This often involves traversing the UI element hierarchy using functions like AXUIElementCopyAttributeValue with attributes like kAXChildrenAttribute.
Permissions: Ensure your application has the necessary permissions to use the Accessibility API. It needs to be added under System Preferences > Security & Privacy > Privacy > Accessibility.
Error Handling: Always include error handling when working with Accessibility APIs, as there can be various reasons for failures (permissions, unavailable attributes, etc.).
API Changes: Keep in mind that macOS APIs can change over time, so always refer to the latest documentation for the Accessibility API.

This approach provides a way to programmatically measure the size of UI elements on macOS, but it requires careful handling of Accessibility API calls and permissions.

Measuring the sizes of the macOS menu bar, an application’s menu bar, and any additional ribbons or toolbars in an application like Excel until you reach the main canvas area is a complex task. It requires accessing and analyzing various UI elements, often with the help of macOS’s Accessibility API. Here’s a general approach to doing this:

The macOS menu bar’s size is typically standard across the system, but it can vary based on user settings and screen resolution. You can programmatically get its height using the System Configuration framework or by directly querying the screen’s properties.

2. Use Accessibility API for Application UI Elements

For getting the size of an application’s menu bar and any additional ribbons or toolbars:

Access the Application’s UI Elements: Using the Accessibility API, access the Excel application’s UI elements.
Identify and Measure Relevant Elements: Identify the elements representing the menu bar, ribbons, and toolbars, and measure their sizes using attributes like kAXSizeAttribute and kAXPositionAttribute.

Example Code in Objective-C

Here is an example of how you might use the Accessibility API in Objective-C. This code assumes you have the required permissions to access the Accessibility API:

#import <Cocoa/Cocoa.h>
#import <ApplicationServices/ApplicationServices.h>

CGFloat GetMenuBarHeight() {
    NSRect screenFrame = [[NSScreen mainScreen] frame];
    NSRect visibleFrame = [[NSScreen mainScreen] visibleFrame];
    return NSHeight(screenFrame) - NSHeight(visibleFrame);
}

AXUIElementRef GetFrontMostApp() {
    pid_t pid;
    NSRunningApplication *frontMostApp = [[NSWorkspace sharedWorkspace] frontmostApplication];
    pid = [frontMostApp processIdentifier];
    return AXUIElementCreateApplication(pid);
}

CGSize GetElementSize(AXUIElementRef element) {
    CGSize size = {0, 0};
    CFTypeRef sizeValue;

    if (AXUIElementCopyAttributeValue(element, kAXSizeAttribute, &sizeValue) == kAXErrorSuccess) {
        AXValueGetValue(sizeValue, kAXValueCGSizeType, &size);
        CFRelease(sizeValue);
    }
    return size;
}

int main() {
    // Get the height of the macOS menu bar
    CGFloat menuBarHeight = GetMenuBarHeight();
    NSLog(@"macOS Menu Bar Height: %f", menuBarHeight);

    // Get the frontmost application (e.g., Excel)
    AXUIElementRef frontMostApp = GetFrontMostApp();

    // Assuming you have a way to access the specific menu bar and ribbon elements
    // ...
    // CGSize appMenuBarSize = GetElementSize(appMenuBarElement);
    // CGSize ribbonSize = GetElementSize(ribbonElement);

    CFRelease(frontMostApp);
    return 0;
}

Considerations

Permissions: Ensure your application or script has the necessary permissions to use the Accessibility API.
Identifying Elements: Identifying specific UI elements like the application’s menu bar or ribbons can be challenging, as it often requires understanding the internal structure of the application’s UI. This can vary between applications and even between different versions of the same application.
Estimation and Approximation: In some cases, you might need to resort to estimation or approximation, especially if exact measurements are difficult to obtain.
Dynamic Layouts: Be aware of dynamic UI changes, such as users customizing toolbars or changing display settings, which can affect the size and position of UI elements.

Getting exact measurements for all these components is complex and might require a detailed understanding of the Excel application’s UI structure, along with proficient use of macOS’s Accessibility API.