Shape Events

In This Topic

NOV Diagram shapes provide various events, which can be used to handle different scenarios. The following table lists the most commonly used shape events:

Event Name	Event Description
MouseDown	Raised when the user presses a mouse button while the mouse pointer is over the shape. Check the Click property of the event handler's argument to see if the event is a single or a double mouse click. See the sample code below this table.
TransformChanged	Raised when the shape transformation has changed.
PageTransformChanged	Raised when the shape transformation to page coordinates has changed.
SizeChanged	Raised when the shape Width or Height has changed.
BeginPointChanged	Raised when the BeginX or BeginY property has changed.
EndPointChanged	Raised when the EndX or EndY property has changed.
GeometryChangedEvent	Raised when any aspect of the shape geometry has changed.
ControlsChangedEvent	Raised when any aspect of the shape control points has changed.
PortsChangedEvent	Raised when any aspect of the shape ports has changed.
BeginPointGlueChangedEvent	Raised when any aspect of the shape begin point glue has changed.
EndPointGlueChangedEvent	Raised when any aspect of the shape end point glue has changed.
MasterGlueChanged	Raised when any aspect of the shape master glue has changed.

The following code demonstrates how to subscribe to the MouseDown event of a shape and how to detect double clicks with the left mouse button:

Shape Mouse Down Event	Copy Code
shape.MouseDown += OnShapeMouseDown; private static void OnShapeMouseDown(NMouseButtonEventArgs arg) { // Check if this is a double click with the left mouse button if (arg.Button == ENMouseButtons.Left && arg.Clicks == 2) { // Get the double-clicked shape NShape shape = arg.TargetNode as NShape; if (shape == null) { shape = arg.TargetNode.GetFirstAncestor<NShape>(); } // Show a message box NMessageBox.Show("Shape double clicked", "Double Click"); } }

Shape Mouse Down Event

Copy Code

shape.MouseDown += OnShapeMouseDown;

private static void OnShapeMouseDown(NMouseButtonEventArgs arg)
{
    // Check if this is a double click with the left mouse button
    if (arg.Button == ENMouseButtons.Left && arg.Clicks == 2)
    {
        // Get the double-clicked shape
        NShape shape = arg.TargetNode as NShape;
        if (shape == null)
        {
            shape = arg.TargetNode.GetFirstAncestor<NShape>();
        }

        // Show a message box
        NMessageBox.Show("Shape double clicked", "Double Click");
    }
}

If you are interested on the MouseDown event of the whole page and to get notified for each double click in the page, check the Page Events topic.