MenuItem.OwnerDraw Eigenschaft

Referenz

Definition

Namespace:: System.Windows.Forms

Assembly:: System.Windows.Forms.dll

Wichtig

Einige Informationen beziehen sich auf Vorabversionen, die vor dem Release ggf. grundlegend überarbeitet werden. Microsoft übernimmt hinsichtlich der hier bereitgestellten Informationen keine Gewährleistungen, seien sie ausdrücklich oder konkludent.

Ruft einen Wert ab, der angibt, ob das Menüelement vom bereitgestellten Code oder von Windows gezeichnet wird, oder legt diesen fest.

public:
 property bool OwnerDraw { bool get(); void set(bool value); };

public bool OwnerDraw { get; set; }

member this.OwnerDraw : bool with get, set

Public Property OwnerDraw As Boolean

Eigenschaftswert

Boolean

true, wenn das Menüelement mithilfe von Code gezeichnet werden soll. false, wenn das Menüelement von Windows gezeichnet werden soll. Der Standardwert ist false.

Beispiele

Im folgenden Codebeispiel wird ein Menü mit einem vom Besitzer gezeichneten Menüelement veranschaulicht. In diesem Beispiel wird die OwnerDraw -Eigenschaft festgelegt und die AddHandler -Anweisung und der AddressOf Operator verwendet, um einen Delegaten zum Behandeln des Ereignisses DrawItem festzulegen. Um das Beispiel auszuführen, fügen Sie es in ein Formular ein, das die SystemNamespaces , System.Windows.Formsund System.Drawing importiert. Rufen Sie InitializeMenu den Konstruktor oder Load die Methode des Formulars auf.

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) );
   }

// Declare the MainMenu control.
internal System.Windows.Forms.MainMenu MainMenu1;

// Declare MenuItem2 as With-Events because it will be user drawn.
internal System.Windows.Forms.MenuItem MenuItem2;

private void InitializeMenu()
{

    // Create MenuItem1, which will be drawn by the operating system.
    MenuItem MenuItem1 = new MenuItem("Regular Menu Item");

    // Create MenuItem2.
    MenuItem2 = new 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 += new DrawItemEventHandler(DrawCustomMenuItem);
    
    // Add the items to the menu.
    MainMenu1 = new MainMenu(new MenuItem[]{MenuItem1, MenuItem2});																													  

    // Add the menu to the form.
    this.Menu = this.MainMenu1;
}

// Draw the custom menu item.
private void DrawCustomMenuItem(object sender, 
    DrawItemEventArgs e)
{

    // Cast the sender to MenuItem so you can access text property.
    MenuItem customItem = (MenuItem) sender;

    // Create a Brush and a Font to draw the MenuItem.
    System.Drawing.Brush aBrush = System.Drawing.Brushes.DarkMagenta;
    Font aFont = new 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, e.Bounds.X, e.Bounds.Y);
    e.Graphics.DrawEllipse(new Pen(System.Drawing.Color.Black, 2),
        new Rectangle(e.Bounds.X, e.Bounds.Y, 
        (System.Int32)stringSize.Width,
        (System.Int32)stringSize.Height));
}

' Declare the MainMenu control.
Friend WithEvents MainMenu1 As System.Windows.Forms.MainMenu

' Declare MenuItem2 as With-Events because it will be user drawn.
Friend WithEvents MenuItem2 As System.Windows.Forms.MenuItem


Private Sub InitializeMenu()

    ' Create MenuItem1, which will be drawn by the operating system.
    Dim MenuItem1 As New MenuItem("Regular Menu Item")

    ' Create MenuItem2.
    MenuItem2 = New 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.
    AddHandler MenuItem2.DrawItem, New DrawItemEventHandler(AddressOf DrawCustomMenuItem)

    ' Add the items to the menu.
    MainMenu1 = New MainMenu(New MenuItem() {MenuItem1, MenuItem2})

    ' Add the menu to the form.
    Me.Menu = Me.MainMenu1
End Sub

' Draw the custom menu item.
Private Sub DrawCustomMenuItem(ByVal sender As Object, ByVal e As _
        System.Windows.Forms.DrawItemEventArgs)

    ' Cast the sender to MenuItem so you can access text property.
    Dim customItem As MenuItem = CType(sender, MenuItem)

    ' Create a Brush and a Font to draw the MenuItem.
    Dim aBrush As System.Drawing.Brush = System.Drawing.Brushes.DarkMagenta
    Dim aFont As New Font("Garamond", 10, FontStyle.Italic, _
        GraphicsUnit.Point)

    ' Get the size of the text to use later to draw an ellipse
    ' around the item.
    Dim stringSize As SizeF = e.Graphics.MeasureString( _
        customItem.Text, aFont)

    ' Draw the item and then draw the ellipse.
    e.Graphics.DrawString(customItem.Text, aFont, _
        aBrush, e.Bounds.X, e.Bounds.Y)
    e.Graphics.DrawEllipse(New Pen(System.Drawing.Color.Black, 2), _
        New Rectangle(e.Bounds.X, e.Bounds.Y, CInt(stringSize.Width), _
        CInt(stringSize.Height)))
End Sub

Hinweise

Wenn die OwnerDraw -Eigenschaft auf truefestgelegt ist, müssen Sie die gesamte Zeichnung des Menüelements behandeln. Mit dieser Funktion können Sie ihre eigenen speziellen Menüanzeigen erstellen.

Gilt für:

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