fix(windows): sync Flutter render surface after SetBounds #582
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Call ForceChildRefresh() after SetWindowPos() in SetBounds() to ensure the Flutter render surface is properly synchronized with the new window size. Problem: When using setSize() or setBounds() to resize the window during app startup, Flutter's render surface may not sync correctly with the new window dimensions. This causes visual artifacts including: - Black areas appearing at window edges - UI elements rendered at incorrect positions - Click events working correctly while visuals are misaligned Root cause: SetWindowPos() triggers WM_SIZE which updates Flutter's logical coordinate system, but the physical render surface viewport may not update in time before the next frame is rendered. Solution: ForceChildRefresh() uses the +1px/-1px resize trick to force the Flutter view child window to fully synchronize its render surface. This is the same mechanism already used for WM_DPICHANGED and leave-full-screen scenarios. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com> Signed-off-by: kaes1a <leehncg@gmail.com>
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Call ForceChildRefresh() after SetWindowPos() in SetBounds() to ensure the Flutter render surface is properly synchronized with the new window size.
Problem:
When using setSize() or setBounds() to resize the window during app startup, Flutter's render surface may not sync correctly with the new window dimensions. This causes visual artifacts including:
Root cause:
SetWindowPos() triggers WM_SIZE which updates Flutter's logical coordinate system, but the physical render surface viewport may not update in time before the next frame is rendered.
Solution:
ForceChildRefresh() uses the +1px/-1px resize trick to force the Flutter view child window to fully synchronize its render surface. This is the same mechanism already used for WM_DPICHANGED and leave-full-screen scenarios.