DrawItemEventHandler Delegate
Represents the method that will handle the DrawItem event of a ComboBox, ListBox, MenuItem, or TabControl control.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
Parameters
- sender
-
Type:
System::Object^
The source of the event.
- e
-
Type:
System.Windows.Forms::DrawItemEventArgs^
A DrawItemEventArgs that contains the event data.
When you create a DrawItemEventArgs delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event handler delegates, see Handling and Raising Events.
The following code example demonstrates a menu with an owner-drawn menu item. This example uses the AddHandler statement and the AddressOf operator to designate a delegate to handle the MenuItem::DrawItem event. To run the example place paste it in a form that imports the System, System.Windows.Forms, and System.Drawing namespaces. Ensure all events are associated with their event-handling methods.
internal: // Declare the MainMenu control. System::Windows::Forms::MainMenu^ MainMenu1; // Declare MenuItem2 as With-Events because it will be user drawn. System::Windows::Forms::MenuItem^ MenuItem2; private: void InitializeMenu() { // Create MenuItem1, which will be drawn by the operating system. MenuItem^ MenuItem1 = gcnew MenuItem( "Regular Menu Item" ); // Create MenuItem2. MenuItem2 = gcnew MenuItem( "Custom Menu Item" ); // Set OwnerDraw property to true. This requires handling the // DrawItem event for this menu item. MenuItem2->OwnerDraw = true; //Add the event-handler delegate to handle the DrawItem event. MenuItem2->DrawItem += gcnew DrawItemEventHandler( this, &Form1::DrawCustomMenuItem ); // Add the items to the menu. array<MenuItem^>^temp0 = {MenuItem1,MenuItem2}; MainMenu1 = gcnew MainMenu( temp0 ); // Add the menu to the form. this->Menu = this->MainMenu1; } // Draw the custom menu item. void DrawCustomMenuItem( Object^ sender, DrawItemEventArgs^ e ) { // Cast the sender to MenuItem so you can access text property. MenuItem^ customItem = dynamic_cast<MenuItem^>(sender); // Create a Brush and a Font to draw the MenuItem. System::Drawing::Brush^ aBrush = System::Drawing::Brushes::DarkMagenta; System::Drawing::Font^ aFont = gcnew System::Drawing::Font( "Garamond",10,FontStyle::Italic,GraphicsUnit::Point ); // Get the size of the text to use later to draw an ellipse // around the item. SizeF stringSize = e->Graphics->MeasureString( customItem->Text, aFont ); // Draw the item and then draw the ellipse. e->Graphics->DrawString( customItem->Text, aFont, aBrush, (float)e->Bounds.X, (float)e->Bounds.Y ); e->Graphics->DrawEllipse( gcnew Pen( System::Drawing::Color::Black,2 ), Rectangle(e->Bounds.X,e->Bounds.Y,(System::Int32)stringSize.Width,(System::Int32)stringSize.Height) ); }
Available since 1.1