TControlCanvas class

In unit Controls

Base class which provides a canvas property used in graphic controls.

Declaration

pascal

TControlCanvas = class(TCanvas)

Inheritance

TControlCanvas
TCanvas
TFPCustomCanvas

Description

TControlCanvas is a TCanvas descendant that implements the base class which provides a canvas used in graphic controls. TControlCanvas extends the ancestor class by including a property representing the TControl associated with the canvas, a window handle for the associated control, and the device context for the handle.

TControlCanvas is used in the implementation of classes like TGraphicControl and TCustomControl, and other visual controls.

Properties

Control public The Control object for which the Canvas is used.

Methods

`CreateHandle`	protected	Ensures that a handle exists for the class instance.
`GetDefaultColor`	protected	Gets the color value used for clDefault.
`Create`	public	Constructor for the class instance.
`Destroy`	public	Destructor for the class instance.
`FreeHandle`	public	Frees the Handle for the control canvas, and its device context when assigned.
`ControlIsPainting`	public	Indicates if the Control has called but not completed its Paint method.

Inherited

From TCanvas (108)

AngleArc AntialiasingMode Arc ArcTo AutoRedraw Brush BrushChanging BrushCopy Changed Changing CheckHelper Chord CopyMode CopyRect CreateBrush CreateFont CreatePen CreateRegion DeselectHandles DoCopyRect DoCreateDefaultBrush DoCreateDefaultFont DoCreateDefaultPen DoDraw DoEllipse DoEllipseAndFill DoEllipseFill DoFloodFill DoGetTextHeight DoGetTextSize DoGetTextWidth DoLine DoLineTo DoLockCanvas DoMoveTo DoPolyBezier DoPolygon DoPolygonAndFill DoPolygonFill DoPolyline DoRectangle DoRectangleAndFill DoRectangleFill DoTextOut DoUnlockCanvas Draw DrawFocusRect Ellipse FillRect FloodFill Font FontChanging Frame Frame3D FrameRect GetClipping GetClipRect GetColor GetHeight GetPixel GetTextMetrics GetUpdatedHandle GetWidth GradientFill Handle HandleAllocated Height Lock OnChange OnChanging Pen PenChanging Pie Pixels PolyBezier Polygon Polyline RadialPie RealizeAntialiasing RealizeAutoRedraw Rectangle Refresh Region RegionChanging RequiredState RestoreHandleState RoundRect SaveHandleState SetClipping SetClipRect SetColor SetHandle SetHeight SetInternalPenPos SetPenPos SetPixel SetWidth StretchDraw TextExtent TextFitInfo TextHeight TextOut TextRect TextStyle TextWidth TryLock Unlock Width

An experiment, built from Lazarus main 2dfa93c66e of 10-22-2026. Not the official Lazarus documentation.