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MenuItem.Popup Event

Definition

Occurs before a menu item's list of menu items is displayed.

public:
 event EventHandler ^ Popup;
public event EventHandler Popup;
member this.Popup : EventHandler 
Public Custom Event Popup As EventHandler 

Event Type

Examples

The following code example demonstrates how to use the Popup event to determine whether MenuItem objects that provide support for cut, copy, and delete operations are enabled before the menu they are displayed in is shown. The example determines if textBox1, a TextBox control on the form, is enabled, has input focus, and has text selected before enabling the MenuItem objects. This example requires that three MenuItem objects are created named menuCut, menuCopy, and menuDelete have been created.

private:
   void PopupMyMenu( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      if ( textBox1->Enabled == false || textBox1->Focused == false || textBox1->SelectedText->Length == 0 )
      {
         menuCut->Enabled = false;
         menuCopy->Enabled = false;
         menuDelete->Enabled = false;
      }
      else
      {
         menuCut->Enabled = true;
         menuCopy->Enabled = true;
         menuDelete->Enabled = true;
      }
   }
private void PopupMyMenu(object sender, System.EventArgs e)
{
   if (textBox1.Enabled == false || textBox1.Focused == false ||
      textBox1.SelectedText.Length == 0)
   {
      menuCut.Enabled = false;
      menuCopy.Enabled = false;
      menuDelete.Enabled = false;
   }
   else
   {
      menuCut.Enabled = true;
      menuCopy.Enabled = true;
      menuDelete.Enabled = true;
   }
}
Private Sub PopupMyMenu(ByVal sender As Object, ByVal e As System.EventArgs) Handles menuEdit.Popup
   If textBox1.Enabled = False OrElse textBox1.Focused = False OrElse textBox1.SelectedText.Length = 0 Then
      menuCut.Enabled = False
      menuCopy.Enabled = False
      menuDelete.Enabled = False
   Else
      menuCut.Enabled = True
      menuCopy.Enabled = True
      menuDelete.Enabled = True
   End If
End Sub

Remarks

This event only occurs when a menu item has submenu items to display. You can use this event handler to add, remove, enable, disable, check, or uncheck menu items based on the state of your application before they are displayed. For more information about handling events, see Handling and Raising Events.

Applies to