Bridges > COM Export Bridge > Examples > Drawable COM Export Examples

# Drawable COM Export Examples

A COM export object that supports graphics must be based on a custom IDL object that inherits from IDLgrWindow, IDLitWindow or IDLitDirectWindow (as described in Exporting Drawable Objects). Additionally, your IDL object must also implement a set of callback methods if you want to be able to respond to mouse or keyboard events in the graphics window. These are described in Event Handling. Examples in this section include:

- COM IDLgrWindow Based Histogram Plot Generator — provides an object based on IDLgrWindow that creates a histogram plot for a selected image file and lets you change the plot linestyle property.
- COM IDLitWindow Surface Manipulation — includes a drawable IDLitWindow example with ISURFACE functionality and a custom method lets you change the active manipulator. Delete key events are captured and passed to a custom OnKeyboard method that deletes selected visualizations.
- Tri-Window COM Export Example — includes controls based on the three types of drawable objects (IDLgrWindow, IDLitWindow, and IDLitDirectWindow) in a single Visual Basic .NET Windows application. A subprocedure captures IDLitComponent::NotifyBridge output and prints it to a label on the form.