[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] Reference for unit 'Controls' (#lcl)

TControlCanvas.FreeHandle

Frees the Handle for the control canvas, and its device context when assigned.

Declaration

Source position: controls.pp line 376

public procedure TControlCanvas.FreeHandle; override;

Description

FreeHandle is an overridden method in TControlCanvas. It calls the inherited method on entry to set the value in Handle to 0 (the unassigned value). If a device context (DC) has been allocated for the window handle (HWND), the ReleaseDC routine is called to release the device context.

FreeHandle is called when a new value is assigned to the Control property, or when the class instance is freed.

See also

TControlCanvas.Destroy

  

Destructor for the class instance.

TControlCanvas.Control

  

The Control object for which the Canvas is used.

TCanvas.Handle

  

Handle (or device context) for the drawing surface.

TCanvas.FreeHandle

  

Frees the Handle for the canvas.

ReleaseDC

  

Releases an Device Context obtained by GetDC.
Version 3.2 Generated 2024-02-25 Home