Troubleshooting TAdvShape: Common Issues and Fixes
1. Shape not rendering or visible
- Cause: Incorrect parent container or sizing.
- Fix: Ensure TAdvShape is placed on a visible container (form/panel) and its Width/Height are > 0. Call Repaint or Invalidate after runtime changes.
2. Incorrect alignment or position
- Cause: Anchors, alignment properties, or dynamic layout code overriding position.
- Fix: Check Align, Anchors, and Margins. If positioning in code, set Left/Top after any parent resize events or use Align with proper parent docking.
3. Unexpected clipping or drawing artifacts
- Cause: Overlapping controls, improper clipping region, or double-buffering disabled.
- Fix: Enable double-buffering on parent or control. Ensure BringToFront/SendToBack ordering is correct. Invalidate the control region when updating.
4. Colors, gradients, or fills not appearing correctly
- Cause: Incorrect Brush/Gradient settings or color format.
- Fix: Verify Brush.Style/Gradient properties and Alpha values. Use solid Brush for testing, then reapply gradients. Ensure Transparent background is handled by parent.
5. Mouse events not firing or incorrect hit testing
- Cause: Control not enabled, HitTest region not set, or parent intercepting events.
- Fix: Ensure Enabled = True, Visible = True. If using custom shapes, set HitTest to include desired regions or override ContainsPoint/HitTest methods. Disable parent controls intercepting events (eg. Transparent panels).
6. Performance issues with complex shapes
- Cause: Repainting every frame, complex path recalculated frequently.
- Fix: Cache computed paths/regions, reduce unnecessary Repaint calls, and use invalidation for minimal regions. Use simpler shapes or lower detail for large-scale rendering.
7. Problems exporting or printing shapes
- Cause: Incompatible canvas or scaling differences.
- Fix: Render to an off-screen bitmap with desired DPI/scale, then export/print that bitmap. Match coordinate systems and apply scaling transforms consistently.
8. Runtime exceptions when changing properties
- Cause: Property set order or nil references.
- Fix: Set dependent properties in correct order (e.g., assign parent/container before setting Align). Guard code with nil checks and try/catch where appropriate.
9. Clipping to non-rectangular shape not working
- Cause: Region not applied correctly or OS limitations.
- Fix: Recreate region after any resize and apply using SetWindowRgn or control Region property. Test on target OS for behavior differences.
10. Visual differences between IDE preview and runtime
- Cause: Design-time defaults vs runtime initialization.
- Fix: Initialize visual properties explicitly in FormCreate or constructor. Avoid reliance on design-time-only resources.
If you want, I can produce code snippets or a checklist tailored to your development environment (Delphi/Lazarus/.NET) — tell me which one.
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