TabControl.DrawItem Zdarzenie

Definicja

Przestrzeń nazw:

System.Windows.Forms

Zestaw:

System.Windows.Forms.dll

Występuje, gdy TabControl należy malować każdą z jego kart, jeśli właściwość jest ustawiona DrawMode na OwnerDrawFixed.

public:
 event System::Windows::Forms::DrawItemEventHandler ^ DrawItem;

public event System.Windows.Forms.DrawItemEventHandler? DrawItem;

member this.DrawItem : System.Windows.Forms.DrawItemEventHandler 

Public Custom Event DrawItem As DrawItemEventHandler 

Typ zdarzenia

DrawItemEventHandler

Przykłady

Poniższy przykład kodu tworzy element z jednym TabPageelementem TabControl . W tym przykładzie zadeklarowana jest procedura obsługi zdarzeń używana do rysowania ciągu i Rectangle na karcie .tabPage1 Procedura obsługi zdarzeń jest powiązana ze zdarzeniem DrawItem .

using namespace System::Drawing;
using namespace System::Windows::Forms;
public ref class Form1: public Form
{
private:
   Rectangle tabArea;
   RectangleF tabTextArea;

public:
   Form1()
   {
      TabControl^ tabControl1 = gcnew TabControl;
      TabPage^ tabPage1 = gcnew TabPage;
      
      // Allows access to the DrawItem event.
      tabControl1->DrawMode = TabDrawMode::OwnerDrawFixed;
      tabControl1->SizeMode = TabSizeMode::Fixed;
      tabControl1->Controls->Add( tabPage1 );
      tabControl1->ItemSize = System::Drawing::Size( 80, 30 );
      tabControl1->Location = Point(25,25);
      tabControl1->Size = System::Drawing::Size( 250, 250 );
      tabPage1->TabIndex = 0;
      ClientSize = System::Drawing::Size( 300, 300 );
      Controls->Add( tabControl1 );
      tabArea = tabControl1->GetTabRect( 0 );
      tabTextArea = tabControl1->GetTabRect( 0 );
      
      // Binds the event handler DrawOnTab to the DrawItem event
      // through the DrawItemEventHandler delegate.
      tabControl1->DrawItem += gcnew DrawItemEventHandler( this, &Form1::DrawOnTab );
   }


private:

   // Declares the event handler DrawOnTab which is a method that
   // draws a String* and Rectangle on the tabPage1 tab.
   void DrawOnTab( Object^ /*sender*/, DrawItemEventArgs^ e )
   {
      Graphics^ g = e->Graphics;
      Pen^ p = gcnew Pen( Color::Blue );
      System::Drawing::Font^ font = gcnew System::Drawing::Font( "Arial",10.0f );
      SolidBrush^ brush = gcnew SolidBrush( Color::Red );
      g->DrawRectangle( p, tabArea );
      g->DrawString( "tabPage1", font, brush, tabTextArea );
   }

};

int main()
{
   Application::Run( gcnew Form1 );
}

using System.Drawing;
using System.Windows.Forms;

public class Form1 : Form
{
    private Rectangle tabArea;
    private RectangleF tabTextArea;

    public Form1()
    {
        TabControl tabControl1 = new TabControl();
        TabPage tabPage1 = new TabPage();

        // Allows access to the DrawItem event. 
        tabControl1.DrawMode = TabDrawMode.OwnerDrawFixed;

        tabControl1.SizeMode = TabSizeMode.Fixed;
        tabControl1.Controls.Add(tabPage1);
        tabControl1.ItemSize = new Size(80, 30);
        tabControl1.Location = new Point(25, 25);
        tabControl1.Size = new Size(250, 250);
        tabPage1.TabIndex = 0;
        ClientSize = new Size(300, 300);
        Controls.Add(tabControl1);

        tabArea = tabControl1.GetTabRect(0);
        tabTextArea = (RectangleF)tabControl1.GetTabRect(0);

        // Binds the event handler DrawOnTab to the DrawItem event 
        // through the DrawItemEventHandler delegate.
        tabControl1.DrawItem += new DrawItemEventHandler(DrawOnTab);
    }

    // Declares the event handler DrawOnTab which is a method that
    // draws a string and Rectangle on the tabPage1 tab.
    private void DrawOnTab(object sender, DrawItemEventArgs e)
    {
        Graphics g = e.Graphics;
        Pen p = new Pen(Color.Blue);
        Font font = new Font("Arial", 10.0f);
        SolidBrush brush = new SolidBrush(Color.Red);

        g.DrawRectangle(p, tabArea);
        g.DrawString("tabPage1", font, brush, tabTextArea);
    }

    static void Main() 
    {
        Application.Run(new Form1());
    }
}

Imports System.Drawing
Imports System.Windows.Forms

Public Class Form1
    Inherits Form
    Private tabArea As Rectangle
    Private tabTextArea As RectangleF

    Public Sub New()
        Dim tabControl1 As New TabControl()
        Dim tabPage1 As New TabPage()

        ' Allows access to the DrawItem event. 
        tabControl1.DrawMode = TabDrawMode.OwnerDrawFixed

        tabControl1.SizeMode = TabSizeMode.Fixed
        tabControl1.Controls.Add(tabPage1)
        tabControl1.ItemSize = New Size(80, 30)
        tabControl1.Location = New Point(25, 25)
        tabControl1.Size = New Size(250, 250)
        tabPage1.TabIndex = 0
        ClientSize = New Size(300, 300)
        Controls.Add(tabControl1)

        tabArea = tabControl1.GetTabRect(0)
        tabTextArea = RectangleF.op_Implicit(tabControl1.GetTabRect(0))

        ' Binds the event handler DrawOnTab to the DrawItem event 
        ' through the DrawItemEventHandler delegate.
        AddHandler tabControl1.DrawItem, AddressOf DrawOnTab
    End Sub

    ' Declares the event handler DrawOnTab which is a method that
    ' draws a string and Rectangle on the tabPage1 tab.
    Private Sub DrawOnTab(ByVal sender As Object, ByVal e As DrawItemEventArgs)
        Dim g As Graphics = e.Graphics
        Dim p As New Pen(Color.Blue)
        Dim font As New Font("Arial", 10.0F)
        Dim brush As New SolidBrush(Color.Red)

        g.DrawRectangle(p, tabArea)
        g.DrawString("tabPage1", font, brush, tabTextArea)
    End Sub

    Shared Sub Main()
        Application.Run(New Form1())
    End Sub
End Class

Uwagi

Po ustawieniu DrawMode właściwości na OwnerDrawFixedwartość , element TabControl zgłasza DrawItem zdarzenie za każdym razem, gdy musi malować jedną z jego kart. Aby dostosować wygląd kart, podaj własny kod malowania w procedurze obsługi zdarzenia DrawItem .

Obiekt TabControl nie obsługuje zmiennych rozmiarów kart z rysunkiem właściciela.

Aby uzyskać więcej informacji na temat obsługi zdarzeń, zobacz Obsługa i podnoszenie zdarzeń.

Zobacz też

• DrawItemEventHandler
• OnDrawItem(DrawItemEventArgs)