This class is used for adding content directly onto a specified iText.Kernel.Pdf.Canvas.PdfCanvas. More...

Inheritance diagram for iText.Layout.Canvas:

Public Member Functions
	Canvas (PdfPage page, Rectangle rootArea)
	Creates a new Canvas to manipulate a specific page content stream. More...

	Canvas (PdfCanvas pdfCanvas, Rectangle rootArea)
	Creates a new Canvas to manipulate a specific content stream, which might be for example a page or iText.Kernel.Pdf.Xobject.PdfFormXObject stream. More...

	Canvas (PdfCanvas pdfCanvas, Rectangle rootArea, bool immediateFlush)
	Creates a new Canvas to manipulate a specific document and page. More...

	Canvas (PdfFormXObject formXObject, PdfDocument pdfDocument)
	Creates a new Canvas to manipulate a specific iText.Kernel.Pdf.Xobject.PdfFormXObject. More...

virtual PdfDocument	GetPdfDocument ()
	Gets the iText.Kernel.Pdf.PdfDocument for this canvas. More...

virtual Rectangle	GetRootArea ()
	Gets the root area rectangle. More...

virtual PdfCanvas	GetPdfCanvas ()
	Gets the iText.Kernel.Pdf.Canvas.PdfCanvas. More...

virtual void	SetRenderer (CanvasRenderer canvasRenderer)
	Sets the iText.Layout.Renderer.IRenderer for this Canvas. More...

virtual PdfPage	GetPage ()
	The page on which this canvas will be rendered. More...

virtual void	EnableAutoTagging (PdfPage page)
	Enables canvas content autotagging. More...

virtual bool	IsAutoTaggingEnabled ()
	Returns true if autotagging of canvas content is enabled. Default value - false.

virtual bool	IsCanvasOfPage ()
	Defines if the canvas is exactly the direct content of the page. More...

virtual void	Relayout ()
	Performs an entire recalculation of the element flow on the canvas, taking into account all its current child elements. More...

virtual void	Flush ()
	Forces all registered renderers (including child element renderers) to flush their contents to the content stream. More...

override void	Close ()
	Closes the Canvas. More...

Public Member Functions inherited from iText.Layout.RootElement< iText.Layout.Canvas >
virtual T	Add (IBlockElement element)
	Adds an element to the root. More...

virtual T	Add (Image image)
	Adds an image to the root. More...

virtual FontProvider	GetFontProvider ()
	Gets iText.Layout.Font.FontProvider if presents. More...

virtual void	SetFontProvider (FontProvider fontProvider)
	Sets iText.Layout.Font.FontProvider. More...

override bool	HasProperty (int property)
	Checks if this entity has the specified property. More...

override bool	HasOwnProperty (int property)
	Checks if this entity has the specified property, i.e. if it was set to this very element earlier More...

override T1	GetProperty< T1 > (int property)
	Gets the property from this entity. More...

override T1	GetOwnProperty< T1 > (int property)
	Gets own property from this entity. More...

override T1	GetDefaultProperty< T1 > (int property)
	Gets the default property from this entity. More...

override void	DeleteOwnProperty (int property)
	Deletes the own property of this entity. More...

override void	SetProperty (int property, Object value)
	Sets a property for this entity. More...

virtual RootRenderer	GetRenderer ()
	Gets the rootRenderer attribute, a specialized iText.Layout.Renderer.IRenderer that acts as the root object that other renderers descend from. More...

virtual T	ShowTextAligned (String text, float x, float y, TextAlignment? textAlign)
	Convenience method to write a text aligned about the specified point More...

virtual T	ShowTextAligned (String text, float x, float y, TextAlignment? textAlign, float angle)
	Convenience method to write a text aligned about the specified point More...

virtual T	ShowTextAligned (String text, float x, float y, TextAlignment? textAlign, VerticalAlignment? vertAlign, float angle)
	Convenience method to write a text aligned about the specified point More...

virtual T	ShowTextAligned (Paragraph p, float x, float y, TextAlignment? textAlign)
	Convenience method to write a text aligned about the specified point More...

virtual T	ShowTextAligned (Paragraph p, float x, float y, TextAlignment? textAlign, VerticalAlignment? vertAlign)
	Convenience method to write a text aligned about the specified point More...

virtual T	ShowTextAligned (Paragraph p, float x, float y, int pageNumber, TextAlignment? textAlign, VerticalAlignment? vertAlign, float radAngle)
	Convenience method to write a text aligned about the specified point More...

virtual T	ShowTextAlignedKerned (String text, float x, float y, TextAlignment? textAlign, VerticalAlignment? vertAlign, float radAngle)
	Convenience method to write a kerned text aligned about the specified point More...

Detailed Description

This class is used for adding content directly onto a specified iText.Kernel.Pdf.Canvas.PdfCanvas.

This class is used for adding content directly onto a specified iText.Kernel.Pdf.Canvas.PdfCanvas. Canvas does not know the concept of a page, so it can't reflow to a 'next' Canvas. This class effectively acts as a bridge between the high-level layout API and the low-level kernel API.

Constructor & Destructor Documentation

◆ Canvas() [1/4]

iText.Layout.Canvas.Canvas	(	PdfPage	page,
		Rectangle	rootArea
	)

inline

Creates a new Canvas to manipulate a specific page content stream.

Creates a new Canvas to manipulate a specific page content stream. The given page shall not be flushed: drawing on flushed pages is impossible because their content is already written to the output stream. Use this constructor to be able to add iText.Layout.Element.Link elements on it (using any other constructor would result in inability to add PDF annotations, based on which, for example, links work).

If the iText.Kernel.Pdf.PdfDocument.IsTagged() is true, using this constructor would automatically enable the tagging for the content. Regarding tagging the effect is the same as using EnableAutoTagging(iText.Kernel.Pdf.PdfPage).

Parameters

page	the page on which this canvas will be rendered, shall not be flushed (see iText.Kernel.Pdf.PdfObjectWrapper.IsFlushed() ).
rootArea	the maximum area that the Canvas may write upon

◆ Canvas() [2/4]

iText.Layout.Canvas.Canvas	(	PdfCanvas	pdfCanvas,
		Rectangle	rootArea
	)

inline

Creates a new Canvas to manipulate a specific content stream, which might be for example a page or iText.Kernel.Pdf.Xobject.PdfFormXObject stream.

Parameters

pdfCanvas	the low-level content stream writer
rootArea	the maximum area that the Canvas may write upon

◆ Canvas() [3/4]

iText.Layout.Canvas.Canvas	(	PdfCanvas	pdfCanvas,
		Rectangle	rootArea,
		bool	immediateFlush
	)

inline

Creates a new Canvas to manipulate a specific document and page.

Parameters

pdfCanvas	The low-level content stream writer
rootArea	The maximum area that the Canvas may write upon
immediateFlush	Whether to flush the canvas immediately after operations, false otherwise

◆ Canvas() [4/4]

iText.Layout.Canvas.Canvas	(	PdfFormXObject	formXObject,
		PdfDocument	pdfDocument
	)

inline

Creates a new Canvas to manipulate a specific iText.Kernel.Pdf.Xobject.PdfFormXObject.

Parameters

formXObject	the form
pdfDocument	the document that the resulting content stream will be written to

Member Function Documentation

◆ Close()

override void iText.Layout.Canvas.Close ( )

inlinevirtual

Closes the Canvas.

Closes the Canvas . Although not completely necessary in all cases, it is still recommended to call this method when you are done working with Canvas object, as due to some properties set there might be some 'hanging' elements, which are waiting other elements to be added and processed. Close() tells the Canvas that no more elements will be added and it is time to finish processing all the elements.

Implements iText.Layout.RootElement< iText.Layout.Canvas >.

◆ EnableAutoTagging()

virtual void iText.Layout.Canvas.EnableAutoTagging ( PdfPage page )

inlinevirtual

Enables canvas content autotagging.

Enables canvas content autotagging. By default it is disabled.

Parameters

page	the page, on which this canvas will be rendered.

◆ Flush()

virtual void iText.Layout.Canvas.Flush ( )

inlinevirtual

Forces all registered renderers (including child element renderers) to flush their contents to the content stream.

◆ GetPage()

virtual PdfPage iText.Layout.Canvas.GetPage ( )

inlinevirtual

The page on which this canvas will be rendered.

Returns: the specified iText.Kernel.Pdf.PdfPage instance, might be null if this the page was not set.

◆ GetPdfCanvas()

virtual PdfCanvas iText.Layout.Canvas.GetPdfCanvas ( )

inlinevirtual

Gets the iText.Kernel.Pdf.Canvas.PdfCanvas.

Returns: the low-level content stream writer

◆ GetPdfDocument()

virtual PdfDocument iText.Layout.Canvas.GetPdfDocument ( )

inlinevirtual

Gets the iText.Kernel.Pdf.PdfDocument for this canvas.

Returns: the document that the resulting content stream will be written to

◆ GetRootArea()

virtual Rectangle iText.Layout.Canvas.GetRootArea ( )

inlinevirtual

Gets the root area rectangle.

Returns: the maximum area that the Canvas may write upon

◆ IsCanvasOfPage()

virtual bool iText.Layout.Canvas.IsCanvasOfPage ( )

inlinevirtual

Defines if the canvas is exactly the direct content of the page.

Defines if the canvas is exactly the direct content of the page. This is known definitely only if this instance was created by Canvas(iText.Kernel.Pdf.PdfPage, iText.Kernel.Geom.Rectangle) constructor overload, otherwise this method returns false.

Returns: true if the canvas on which this instance performs drawing is directly the canvas of the page; false if the instance of this class was created not with Canvas(iText.Kernel.Pdf.PdfPage, iText.Kernel.Geom.Rectangle) constructor overload.

◆ Relayout()

virtual void iText.Layout.Canvas.Relayout ( )

inlinevirtual

Performs an entire recalculation of the element flow on the canvas, taking into account all its current child elements.

Performs an entire recalculation of the element flow on the canvas, taking into account all its current child elements. May become very resource-intensive for large documents. Do not use when you have set RootElement.immediateFlush to true.

◆ SetRenderer()

virtual void iText.Layout.Canvas.SetRenderer ( CanvasRenderer canvasRenderer )

inlinevirtual

Sets the iText.Layout.Renderer.IRenderer for this Canvas.

Parameters

canvasRenderer a renderer specific for canvas operations

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ Canvas() [1/4]

◆ Canvas() [2/4]

◆ Canvas() [3/4]

◆ Canvas() [4/4]

Member Function Documentation

◆ Close()

◆ EnableAutoTagging()

◆ Flush()

◆ GetPage()

◆ GetPdfCanvas()

◆ GetPdfDocument()

◆ GetRootArea()

◆ IsCanvasOfPage()

◆ Relayout()

◆ SetRenderer()