MeasureItemEventArgs MeasureItemEventArgs MeasureItemEventArgs MeasureItemEventArgs Class

定義

ListBoxComboBoxCheckedListBoxMenuItem の各コントロールの MeasureItem イベントのデータを提供します。Provides data for the MeasureItem event of the ListBox, ComboBox, CheckedListBox, and MenuItem controls.

public ref class MeasureItemEventArgs : EventArgs
public class MeasureItemEventArgs : EventArgs
type MeasureItemEventArgs = class
    inherit EventArgs
Public Class MeasureItemEventArgs
Inherits EventArgs
継承
MeasureItemEventArgsMeasureItemEventArgsMeasureItemEventArgsMeasureItemEventArgs

次のコード例は、使用する方法を示します、Graphicsプロパティ内の項目のカスタム描画を実行する、ListBoxします。The following code example demonstrates how to use the Graphics property to perform custom drawing of the items in a ListBox.

public ref class Form1: public System::Windows::Forms::Form
{
private:
   System::Windows::Forms::ListBox^ listBox1;
   System::ComponentModel::Container^ components;

public:
   ~Form1()
   {
      if ( components != nullptr )
      {
         delete components;
      }
   }

private:

   /// <summary>
   /// Required method for Designer support - do not modify
   /// the contents of this method with the code editor.
   /// </summary>
   void InitializeComponent()
   {
      this->listBox1 = gcnew System::Windows::Forms::ListBox;
      this->SuspendLayout();

      // 
      // listBox1
      // 
      this->listBox1->DrawMode = System::Windows::Forms::DrawMode::OwnerDrawVariable;
      this->listBox1->Location = System::Drawing::Point( 16, 48 );
      this->listBox1->Name = "listBox1";
      this->listBox1->SelectionMode = System::Windows::Forms::SelectionMode::MultiExtended;
      this->listBox1->Size = System::Drawing::Size( 256, 134 );
      this->listBox1->TabIndex = 0;
      this->listBox1->MeasureItem += gcnew System::Windows::Forms::MeasureItemEventHandler( this, &Form1::listBox1_MeasureItem );
      this->listBox1->DrawItem += gcnew System::Windows::Forms::DrawItemEventHandler( this, &Form1::listBox1_DrawItem );

      // 
      // Form1
      // 
      this->ClientSize = System::Drawing::Size( 292, 273 );
      array<System::Windows::Forms::Control^>^temp0 = {this->listBox1};
      this->Controls->AddRange( temp0 );
      this->Name = "Form1";
      this->Text = "Form1";
      this->ResumeLayout( false );
   }

   void listBox1_MeasureItem( Object^ /*sender*/, MeasureItemEventArgs^ e )
   {
      System::Drawing::Font^ font = (dynamic_cast<ListBoxFontItem^>(listBox1->Items[ e->Index ]))->Font;
      SizeF stringSize = e->Graphics->MeasureString( font->Name, font );
      
      // Set the height and width of the item
      e->ItemHeight = (int)stringSize.Height;
      e->ItemWidth = (int)stringSize.Width;
   }

   // For efficiency, cache the brush to use for drawing.
   SolidBrush^ foreColorBrush;
   void listBox1_DrawItem( Object^ /*sender*/, DrawItemEventArgs^ e )
   {
      Brush^ brush;

      // Create the brush using the ForeColor specified by the DrawItemEventArgs
      if ( foreColorBrush == nullptr )
            foreColorBrush = gcnew SolidBrush( e->ForeColor );
      else
      if ( foreColorBrush->Color != e->ForeColor )
      {
         // The control's ForeColor has changed, so dispose of the cached brush and
         // create a new one.
         delete foreColorBrush;
         foreColorBrush = gcnew SolidBrush( e->ForeColor );
      }

      // Select the appropriate brush depending on if the item is selected.
      // Since State can be a combinateion (bit-flag) of enum values, you can't use
      // "==" to compare them.
      if ( (e->State & DrawItemState::Selected) == DrawItemState::Selected )
            brush = SystemBrushes::HighlightText;
      else
            brush = foreColorBrush;

      // Perform the painting.
      System::Drawing::Font^ font = (dynamic_cast<ListBoxFontItem^>(listBox1->Items[ e->Index ]))->Font;
      e->DrawBackground();
      e->Graphics->DrawString( font->Name, font, brush, e->Bounds );
      e->DrawFocusRectangle();
   }

public:

   /// <summary>
   ///  A wrapper class for use with storing Fonts in a ListBox.  Since ListBox uses the
   ///  ToString() of its items for the text it displays, this class is needed to return
   ///  the name of the font, rather than its ToString() value.
   /// </summary>
   ref class ListBoxFontItem
   {
   public:
      System::Drawing::Font^ Font;
      ListBoxFontItem( System::Drawing::Font^ f )
      {
         Font = f;
      }

      virtual String^ ToString() override
      {
         return Font->Name;
      }
   };
};

[STAThread]
int main()
{
   Application::Run( gcnew Form1 );
}
 public class Form1 : System.Windows.Forms.Form
 {
    private System.Windows.Forms.ListBox listBox1;
    private System.ComponentModel.Container components = null;


    protected override void Dispose(bool disposing)
    {
       if( disposing )
       {
          if ( components != null ) 
             components.Dispose();

          if ( foreColorBrush != null )
             foreColorBrush.Dispose();
       }
       base.Dispose(disposing);
    }

#region Windows Form Designer generated code
    /// <summary>
    /// Required method for Designer support - do not modify
    /// the contents of this method with the code editor.
    /// </summary>
    private void InitializeComponent()
    {
       this.listBox1 = new System.Windows.Forms.ListBox();
       this.SuspendLayout();
       // 
       // listBox1
       // 
       this.listBox1.DrawMode = System.Windows.Forms.DrawMode.OwnerDrawVariable;
       this.listBox1.Location = new System.Drawing.Point(16, 48);
       this.listBox1.Name = "listBox1";
       this.listBox1.SelectionMode = System.Windows.Forms.SelectionMode.MultiExtended;
       this.listBox1.Size = new System.Drawing.Size(256, 134);
       this.listBox1.TabIndex = 0;
       this.listBox1.MeasureItem += new System.Windows.Forms.MeasureItemEventHandler(this.listBox1_MeasureItem);
       this.listBox1.DrawItem += new System.Windows.Forms.DrawItemEventHandler(this.listBox1_DrawItem);
       // 
       // Form1
       // 
       this.ClientSize = new System.Drawing.Size(292, 273);
       this.Controls.AddRange(new System.Windows.Forms.Control[] {
                                                                    this.listBox1});
       this.Name = "Form1";
       this.Text = "Form1";
       this.ResumeLayout(false);

    }
#endregion

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

    private void listBox1_MeasureItem(object sender, System.Windows.Forms.MeasureItemEventArgs e)
    {
       Font font = ((ListBoxFontItem)listBox1.Items[e.Index]).Font;
       SizeF stringSize = e.Graphics.MeasureString(font.Name, font);

       // Set the height and width of the item
       e.ItemHeight = (int)stringSize.Height;
       e.ItemWidth = (int)stringSize.Width;
    }

    // For efficiency, cache the brush to use for drawing.
    private SolidBrush foreColorBrush;

    private void listBox1_DrawItem(object sender, System.Windows.Forms.DrawItemEventArgs e)
    {
       Brush brush;

       // Create the brush using the ForeColor specified by the DrawItemEventArgs
       if ( foreColorBrush == null )
          foreColorBrush = new SolidBrush(e.ForeColor);
       else if ( foreColorBrush.Color != e.ForeColor )
       {
          // The control's ForeColor has changed, so dispose of the cached brush and
          // create a new one.
          foreColorBrush.Dispose();
          foreColorBrush = new SolidBrush(e.ForeColor);
       }

       // Select the appropriate brush depending on if the item is selected.
       // Since State can be a combinateion (bit-flag) of enum values, you can't use
       // "==" to compare them.
       if ( (e.State & DrawItemState.Selected) == DrawItemState.Selected )
          brush = SystemBrushes.HighlightText;
       else
          brush = foreColorBrush;

       // Perform the painting.
       Font font = ((ListBoxFontItem)listBox1.Items[e.Index]).Font;
       e.DrawBackground();
       e.Graphics.DrawString(font.Name, font, brush, e.Bounds);
       e.DrawFocusRectangle();
    }

    /// <summary>
    ///  A wrapper class for use with storing Fonts in a ListBox.  Since ListBox uses the
    ///  ToString() of its items for the text it displays, this class is needed to return
    ///  the name of the font, rather than its ToString() value.
    /// </summary>
    public class ListBoxFontItem 
    {
       public Font Font;

       public ListBoxFontItem(Font f) 
       {
          Font = f;
       }

       public override string ToString() 
       {
          return Font.Name;
       }
    }
 }
Public Class Form1
   Inherits System.Windows.Forms.Form
   Private WithEvents listBox1 As System.Windows.Forms.ListBox
   Private components As System.ComponentModel.Container = Nothing

   Private FontSize As Single = 12.0F

   '
   '  This sample displays a ListBox that contains a list of all the fonts
   '  installed on the system and draws each item in its respective font.
   '
   Public Sub New()
      InitializeComponent()

      ' Populate control with the fonts installed on the system.
      Dim families As FontFamily() = FontFamily.Families

      Dim family As FontFamily
      For Each family In families
         Dim style As FontStyle = FontStyle.Regular

         ' Monotype Corsiva is only available in italic
         If family.Name = "Monotype Corsiva" Then
            style = style Or FontStyle.Italic
         End If

         listBox1.Items.Add(New ListBoxFontItem(New Font(family.Name, FontSize, style, GraphicsUnit.Point)))
      Next family
   End Sub


   Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
      If disposing Then
         If (components IsNot Nothing) Then
            components.Dispose()
         End If

         If (foreColorBrush IsNot Nothing) Then
            foreColorBrush.Dispose()
         End If
      End If

      MyBase.Dispose(disposing)
   End Sub

   Private Sub InitializeComponent()
      Me.listBox1 = New System.Windows.Forms.ListBox()
      Me.SuspendLayout()
      ' 
      ' listBox1
      ' 
      Me.listBox1.DrawMode = System.Windows.Forms.DrawMode.OwnerDrawVariable
      Me.listBox1.Location = New System.Drawing.Point(16, 48)
      Me.listBox1.Name = "listBox1"
      Me.listBox1.SelectionMode = System.Windows.Forms.SelectionMode.MultiExtended
      Me.listBox1.Size = New System.Drawing.Size(256, 134)
      Me.listBox1.TabIndex = 0
      ' 
      ' Form1
      ' 
      Me.ClientSize = New System.Drawing.Size(292, 273)
      Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.listBox1})
      Me.Name = "Form1"
      Me.Text = "Form1"
      Me.ResumeLayout(False)
   End Sub

   <STAThread()> Shared Sub Main()
      Application.Run(New Form1())
   End Sub

   Private Sub listBox1_MeasureItem(ByVal sender As Object, ByVal e As System.Windows.Forms.MeasureItemEventArgs) Handles listBox1.MeasureItem
      Dim font As Font = CType(listBox1.Items(e.Index), ListBoxFontItem).Font
      Dim stringSize As SizeF = e.Graphics.MeasureString(font.Name, font)

      ' Set the height and width of the item
      e.ItemHeight = CInt(stringSize.Height)
      e.ItemWidth = CInt(stringSize.Width)
   End Sub

   ' For efficiency, cache the brush used for drawing.
   Private foreColorBrush As SolidBrush

   Private Sub listBox1_DrawItem(ByVal sender As Object, ByVal e As System.Windows.Forms.DrawItemEventArgs) Handles listBox1.DrawItem
      Dim brush As Brush

      ' Create the brush using the ForeColor specified by the DrawItemEventArgs
      If foreColorBrush Is Nothing Then
         foreColorBrush = New SolidBrush(e.ForeColor)
      Else
         If Not foreColorBrush.Color.Equals(e.ForeColor) Then
            ' The control's ForeColor has changed, so dispose of the cached brush and
            ' create a new one.
            foreColorBrush.Dispose()
            foreColorBrush = New SolidBrush(e.ForeColor)
         End If
      End If

      ' Select the appropriate brush depending on if the item is selected.
      ' Since State can be a combinateion (bit-flag) of enum values, you can't use
      ' "==" to compare them.
      If (e.State And DrawItemState.Selected) = DrawItemState.Selected Then
         brush = SystemBrushes.HighlightText
      Else
         brush = foreColorBrush
      End If

      ' Perform the painting.
      Dim font As Font = CType(listBox1.Items(e.Index), ListBoxFontItem).Font
      e.DrawBackground()
      e.Graphics.DrawString(font.Name, font, brush, e.Bounds.X, e.Bounds.Y)
      e.DrawFocusRectangle()
   End Sub

   '
   '  A wrapper class for use with storing Fonts in a ListBox.  Since ListBox uses the
   '  ToString() of its items for the text it displays, this class is needed to return
   '  the name of the font, rather than its ToString() value.
   '
   Public Class ListBoxFontItem
      Public Font As Font

      Public Sub New(ByVal f As Font)
         Font = f
      End Sub

      Public Overrides Function ToString() As String
         Return Font.Name
      End Function
   End Class
End Class

注釈

このイベントが送信されるときに、OwnerDrawプロパティのListBoxComboBoxCheckedListBox、またはMenuItemに設定されているtrueします。This event is sent when the OwnerDraw property of ListBox, ComboBox, CheckedListBox, or MenuItem is set to true. 描画関数項目のサイズを変更する方法を通知に使用されます。It is used to tell the drawing function how to size an item.

イベント モデルについては、次を参照してください。処理とイベントの発生します。For information about the event model, see Handling and Raising Events.

コンストラクター

MeasureItemEventArgs(Graphics, Int32) MeasureItemEventArgs(Graphics, Int32) MeasureItemEventArgs(Graphics, Int32) MeasureItemEventArgs(Graphics, Int32)

MeasureItemEventArgs クラスの新しいインスタンスを初期化します。Initializes a new instance of the MeasureItemEventArgs class.

MeasureItemEventArgs(Graphics, Int32, Int32) MeasureItemEventArgs(Graphics, Int32, Int32) MeasureItemEventArgs(Graphics, Int32, Int32) MeasureItemEventArgs(Graphics, Int32, Int32)

項目の高さに対するパラメーターを指定して、MeasureItemEventArgs クラスの新しいインスタンスを初期化します。Initializes a new instance of the MeasureItemEventArgs class providing a parameter for the item height.

プロパティ

Graphics Graphics Graphics Graphics

計測対象となる Graphics オブジェクトを取得します。Gets the Graphics object to measure against.

Index Index Index Index

高さと幅が必要な項目のインデックスを取得します。Gets the index of the item for which the height and width is needed.

ItemHeight ItemHeight ItemHeight ItemHeight

Index で指定した項目の高さを取得または設定します。Gets or sets the height of the item specified by the Index.

ItemWidth ItemWidth ItemWidth ItemWidth

Index で指定した項目の幅を取得または設定します。Gets or sets the width of the item specified by the Index.

メソッド

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

指定したオブジェクトが、現在のオブジェクトと等しいかどうかを判断します。Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode() GetHashCode() GetHashCode() GetHashCode()

既定のハッシュ関数として機能します。Serves as the default hash function.

(Inherited from Object)
GetType() GetType() GetType() GetType()

現在のインスタンスの Type を取得します。Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

現在の Object の簡易コピーを作成します。Creates a shallow copy of the current Object.

(Inherited from Object)
ToString() ToString() ToString() ToString()

現在のオブジェクトを表す文字列を返します。Returns a string that represents the current object.

(Inherited from Object)

適用対象

こちらもご覧ください