LayoutGroup.CustomDrawHeaderButton Event

Allows you to custom paint header buttons (LayoutGroup.CustomHeaderButtons).

Namespace: DevExpress.XtraLayout

Assembly: DevExpress.XtraLayout.v20.1.dll

Declaration

[DXCategory("Appearance")]
public virtual event GroupBoxButtonCustomDrawEventHandler CustomDrawHeaderButton
<DXCategory("Appearance")>
Public Overridable Event CustomDrawHeaderButton As GroupBoxButtonCustomDrawEventHandler

Event Data

The CustomDrawHeaderButton event's data class is DevExpress.XtraEditors.GroupBoxButtonCustomDrawEventArgs.

Remarks

The CustomDrawHeaderButton event allows you to custom paint header buttons (LayoutGroup.CustomHeaderButtons). The Button event parameter idenfies the currently processed button.

To draw custom information, use the methods provided by the Cache or Graphics event parameter.

When you handle the CustomDrawHeaderButton event, you can invoke the default rendering of the button or its individual elements with the following methods:

  • DefaultDraw - Performs the button's default rendering (including all its elements)
  • DefaultDrawBackground - Performs the default rendering of the button's background.
  • DefaultDrawImage - Performs the default rendering of the button's image (Button.ImageOptions).
  • DefaultDrawText - Performs the default rendering of the button's text (Button.Caption)

Set the Handled event parameter to true to indicate that you have handled the CustomDrawHeaderButton event and no default painting is required after your event handler is completed. If the event's Handled parameter is set to false (the default value), the default painting mechanism will automatically be invoked after your custom draw event handler is completed. The default painting mechanism overrides all rendering you may have performed previously.

See the LayoutControl.CustomDraw topic for more information.

IMPORTANT

Do not change cell values, modify the control's layout, or change the control's object model in the events used for custom control painting. Actions that update the layout can cause the control to malfunction.

See Also