


How Can I Enable Keyboard Navigation in a Custom Panel Control for Layer Manipulation?
Jan 21, 2025 am 12:18 AMEnabling Keyboard Navigation in a Custom Layer Control Panel
A user encountered issues with keyboard navigation in a custom panel designed for layer manipulation within a graphics application. The panel, derived from the Panel
class, wasn't responding to keyboard input or focus events.
The solution involved directly modifying the Panel
class to address this:
-
Enabling Focus: The
SetStyle
method was modified to enable the selectable property, making the control focusable. -
Focus on Mouse Click: The
OnMouseDown
event handler was overridden to programmatically set focus to the control when clicked. -
Handling Cursor Keys: The
IsInputKey
method was extended to recognize and process up, down, left, and right arrow keys. -
Focus Rectangle Management: The
OnEnter
andOnLeave
events were overridden to redraw the control's client area, ensuring the focus rectangle appears and disappears correctly. -
Drawing the Focus Rectangle: The
OnPaint
event was overridden to draw a visual focus rectangle around the control when it has focus.
These changes ensure the custom panel correctly receives focus and responds to keyboard input, enabling the desired layer navigation functionality. The provided code demonstrates the modified class implementing this behavior.
The above is the detailed content of How Can I Enable Keyboard Navigation in a Custom Panel Control for Layer Manipulation?. For more information, please follow other related articles on the PHP Chinese website!

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