TCustomTreeView.OnCustomDrawArrow property
Event handler signalled to custom draw expand / collapse (fold) indicators for a tree node.
Declaration
property OnCustomDrawArrow: TTVCustomDrawArrowEvent read FOnCustomDrawArrow write FOnCustomDrawArrow;Description
OnCustomDrawArrow is a
TTVCustomDrawArrowEvent property
with the event handler signalled to custom-draw the expand/collapse (fold)
indicator for a node on the tree view control.
Arguments to the event handler include:
- Sender
- The tree view control for the event notification.
- ARect
- TRect instance with the bounds on the drawing area where the indicator should be drawn.
- ACollapsed
- Boolean value which indicates which indicator (expanded or collapsed) to to draw on the tree view control. True indicates that the collapsed arrow should be drawn.
Use the Canvas for the control to perform drawing operations in the handler routine.
OnCustomDrawArrow is signalled (when assigned) from the DoPaintNode method. If OnCustomDrawArrow has not been assigned, the default drawing routines in the class are used to paint the indicator using the style in the ExpandSignType, ExpandSignSize, ExpandSignWidth, and ExpandSignColor properties.
See also
An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.