ArcObjects Library Reference (Display)

IDisplay Interface

Provides access to members that control the Display.

Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

When To Use

Use the IDisplay interface to draw points, lines, polygons, rectangles, and text on a device.

Members

	Name	Description
	ClipEnvelope	The bounds of the invalid region. Use after StartDrawing and before FinishDrawing.
	ClipEnvelopes	The invalid region as a set of envelopes. Use after StartDrawing and before FinishDrawing.
	ClipGeometry	User-specified clip shape. This shape is merged with the invalid region to arrive at the actual clip region. Must be specified before StartDrawing.
	DisplayTransformation	The transformation used by the display.
	DrawMultipoint	Draws specified multipoint on the display.
	DrawPoint	Draws specified point on the display.
	DrawPolygon	Draws specified polygon on the display.
	DrawPolyline	Draws specified line on the display.
	DrawRectangle	Draws specified rectangle on the display.
	DrawText	Draws specified text on the display.
	Filter	Display filter. Must call while in a StartDrawing-FinishDrawing sequence. Set Filter to 0 to resume normal drawing.
	FinishDrawing	Completes drawing.
	hDC	The device context that the display is currently drawing to. Only valid between calls to StartDrawing and FinishDrawing.
	hPalette	Palette.
	IlluminationProps	Illumination properties used by the display.
	Progress	Call frequently during drawing process.
	SetSymbol	Sets the symbol used for drawing. Four different symbols can be specified simultaneously: Marker, Line, Fill, Text.
	StartDrawing	Prepare the display for drawing. Specify the device context and the cache to draw to (normally esriNoScreenCache). The ScreenDisplay coclass will automatically create a window device context if you specify hdc=0.
	SuppressEvents	Indicates if display object suppresses events.

CoClasses that implement IDisplay

CoClasses and Classes	Description
AppDisplay (esriArcMapUI)	Esri Display.
ScreenDisplay	Display class for drawing to window.
SimpleDisplay	Display class for drawing to any HDC.

Remarks

The Display objects, those that implement IDisplay, are a set of objects which allow application developers to easily draw graphics on a variety of output devices. These objects allow you to render shapes stored in real-world coordinates to a screen, printer, or export file.

The IDisplay interface abstracts a drawing surface. A drawing surface is simply any hardware device, export file, or memory bitmap that can be represented by a Windows Device Context. Each display manages its own DisplayTransformation object which handles the conversion of coordinates from real-world space to device space and back.

There are currently two Display objects: ScreenDisplay and SimpleDisplay. The ScreenDisplay object abstracts a normal application window and implements scrolling and backing store. The SimpleDisplay abstracts all other devices that can be rendered to using a Windows Device Context such as printers and metafiles.

.NET Snippets

.NET Samples

Dynamic logo (Code Files: DynamicLogo) | Dynamic display animated zoom (Code Files: AnimatedZoomInTool AnimatedZoomOutTool) | Dynamic biking (Code Files: DynamicBikingCmd) | Implementing a schematic digitizing tool (Code Files: DigitTool) | Dynamic display�tracking dynamic object (Code Files: TrackObject) | Edit event listener (Code Files: EventListener) | Move a graphic along a path in ArcMap (Code Files: MapGraphicKeyframe) | RSS weather layer (Code Files: RSSWeatherLayerClass) | Multivariate renderer (Code Files: MultivariateRenderer) | Triangle graphic element (Code Files: TriangleElementClass)

.NET Related Topics

Best practices for using dynamic display | Getting started with dynamic display | How to plug in dynamic drawing | How to wire custom events using IActiveViewEvents