TPrinterCanvas class

In unit Printers

Implements a canvas used for TPrinter device output.

Declaration

pascal

TPrinterCanvas = class(TCanvas)

Inheritance

TPrinterCanvas
TCanvas
TFPCustomCanvas

Descends from it: TFilePrinterCanvas

Description

TPrinterCanvas is a TCanvas descendant which implements a canvas used to position, format, and output values from a TPrinter print device. The TPrinter instance which provides the capabilities for the device is passed as an argument to the constructor, and stored in the Printer property.

TPrinterCanvas provides methods which mirror the operations performed in TPrinter, like: BeginDoc, NewPage, BeginPage, EndPage and EndDoc. Methods in the canvas are called from the corresponding methods in TPrinter when its RawMode property is set to False.

A TPrinterCanvas (or descendant) class reference is used to implement the TPrinter.CanvasClass property.

Properties

`Printer`	public	Device which uses the canvas to print a document.
`Title`	public	Title for the document rendered using the printer canvas.
`PageHeight`	public	Size of the printable area for the page on the vertical axis.
`PageWidth`	public	Size of the printable area for the page on the horizontal axis.
`PaperWidth`	public	Horizontal size for the paper selected in the print device.
`PaperHeight`	public	Vertical size for the paper selected in the print device.
`PageNumber`	public	The number for the current page in the printer canvas.
`TopMargin`	public	The size of the margin at the top of the canvas.
`LeftMargin`	public	The size of the margin at the left edge of the canvas.
`BottomMargin`	public	The size of the margin at the bottom edge of the canvas.
`RightMargin`	public	The size of the margin at the right edge of the canvas.
`Orientation`	public	Orientation of the page on the selected paper.
`XDPI`	public	DPI (Dots per Inch) in the horizontal direction for the print device.
`YDPI`	public	DPI (Dots per Inch) in the vertical direction for the print device.

Methods

`GetLeftMargin`	protected	Gets the value for the LeftMargin property.
`GetTopMargin`	protected	Gets the value for the TopMargin property.
`GetBottomMargin`	protected	Gets the value for the BottomMargin property.
`GetRightMargin`	protected	Gets the value for the RightMargin property.
`Create`	public	Constructor for the class instance.
`BeginDoc`	public	Performs actions needed to start printing a document.
`NewPage`	public	Performs actions needed when a new page is started.
`BeginPage`	public	Performs actions needed when a page is started.
`EndPage`	public	Performs actions needed when a page is completed.
`EndDoc`	public	Performs actions needed when a document has finished printing.
`Changing`	public	Signals the OnChanging event when the printer status is changed.

Inherited

From TCanvas (111)

AngleArc AntialiasingMode Arc ArcTo AutoRedraw Brush BrushChanging BrushCopy Changed CheckHelper Chord CopyMode CopyRect CreateBrush CreateFont CreateHandle CreatePen CreateRegion DeselectHandles Destroy 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 FreeHandle GetClipping GetClipRect GetColor GetDefaultColor 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 development snapshots. Not the official Free Pascal or Lazarus documentation.