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Handle (or device context) for the drawing surface.
Source position: graphics.pp line 1175
public property TCanvas.Handle : HDC |
Handle is a HDC property that provides the device context for the drawing surface. A valid Handle is required for nearly all operations performed on the canvas.
Read access calls RequiredState, and allocates a Handle by calling CreateHandle if one does not already exist. An EInvalidGraphicOperation exception may be raised in the method if a valid handle cannot be acquired.
| Remark: | CreateHandle is an empty implementation in TCanvas, and is overridden in descendent classes to return a handle for an image format or output device. See TBitmapCanvas, TControlCanvas, TPrinterCanvas, et. al. |
Setting a new value for Handle causes saved Brush, Pen, and Font handles to be reset to their default values. The AntialiasingMode for the canvas is also re-applied.
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Ensures that all handles needed for the canvas are valid. |
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Creates a new Handle for the Canvas. |
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Deselects all sub-handles in the current device context. |
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The Brush used to paint on the Canvas. |
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The Pen to be used for writing in this canvas. |
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Contains the Font used to render text on the drawing surface. |
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EInvalidGraphicOperation - exception handler for invalid graphic operation. |
| Version 3.2 | Generated 2024-02-25 | Home |