If the chart is not refreshing while the loop is running, it’s likely due to Excel not updating the screen between the changes. Excel VBA often batches screen updates to improve performance, but in the case of an animation, we need the screen to update with each change.
To ensure the chart updates with each iteration of the loop, you can use the Application.ScreenUpdating property in VBA. Setting this property to True forces Excel to update the screen with each change. Here’s how to incorporate it into your script:
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Enable Screen Updating: At the beginning of your subroutine, set Application.ScreenUpdating to True.
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Disable Screen Updating After Completion: It’s a good practice to turn off screen updating once your subroutine completes, to restore normal performance.
Here’s your revised script with screen updating enabled:
Declare PtrSafe Sub usleep Lib "libc.dylib" (ByVal microseconds As Long)
Sub AnimateSineWaveChartWithScreenUpdating()
Application.ScreenUpdating = True ' Enable screen updating
Set ws = ThisWorkbook.Sheets("Sheet1")
Set chartRange = ws.Range("B2:B11") ' Adjust to your data range
Dim i As Long, j As Integer
waveSpeed = 0.2 ' Adjust for different speeds of the wave
Dim valuesArray() As Double
ReDim valuesArray(1 To chartRange.Rows.Count, 1 To 1) ' Array to store new values
For i = 0 To 100 ' Number of frames in the animation
For j = 1 To chartRange.Rows.Count
' Calculate sine wave value for each point
valuesArray(j, 1) = Sin(waveSpeed * i + j)
chartRange.Value = valuesArray ' Update all values at once
usleep 50000 ' 50 milliseconds delay
Application.Wait (Now + TimeValue("0:00:01")) ' Fallback for non-Mac systems
DoEvents ' Keep Excel responsive
Application.ScreenUpdating = False ' Disable screen updating after completion
In this script, Application.ScreenUpdating = True is set at the beginning of the subroutine to ensure that Excel updates the screen with each change to the chart. After the loop, it’s set back to False to restore normal behavior.
This should resolve the issue with the chart not refreshing during the animation. As always, the performance and smoothness will depend on various factors like the complexity of the workbook and the system’s capabilities.