MeasureItemEventArgs Class
Provides data for the MeasureItem event of the ListBox, ComboBox, CheckedListBox, and MenuItem controls.
For a list of all members of this type, see MeasureItemEventArgs Members.
System.Object
System.EventArgs
System.Windows.Forms.MeasureItemEventArgs
[Visual Basic] Public Class MeasureItemEventArgs Inherits EventArgs [C#] public class MeasureItemEventArgs : EventArgs [C++] public __gc class MeasureItemEventArgs : public EventArgs [JScript] public class MeasureItemEventArgs extends EventArgs
Thread Safety
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
Remarks
This event is sent when the OwnerDraw property of ListBox, ComboBox, CheckedListBox, or MenuItem is set to true. It is used to tell the drawing function how to size an item.
For information about the event model, see Events and Delegates.
Example
[Visual Basic] 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 Not (components Is Nothing) Then components.Dispose() End If If Not (foreColorBrush Is 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.AutoScaleBaseSize = New System.Drawing.Size(5, 13) 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 [C#] 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.AutoScaleBaseSize = new System.Drawing.Size(5, 13); 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; } } } [C++] public __gc class Form1 : public System::Windows::Forms::Form { private: System::Windows::Forms::ListBox* listBox1; System::ComponentModel::Container* components; protected: void Dispose(bool disposing) { if( disposing ) { if ( components != 0 ) components->Dispose(); if ( foreColorBrush != 0 ) foreColorBrush->Dispose(); } Form::Dispose(disposing); } /// <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 = System::Drawing::Point(16, 48); this->listBox1->Name = S"listBox1"; this->listBox1->SelectionMode = System::Windows::Forms::SelectionMode::MultiExtended; this->listBox1->Size = System::Drawing::Size(256, 134); this->listBox1->TabIndex = 0; this->listBox1->MeasureItem += new System::Windows::Forms::MeasureItemEventHandler(this, &Form1::listBox1_MeasureItem); this->listBox1->DrawItem += new System::Windows::Forms::DrawItemEventHandler(this, &Form1::listBox1_DrawItem); // // Form1 // this->AutoScaleBaseSize = System::Drawing::Size(5, 13); this->ClientSize = System::Drawing::Size(292, 273); System::Windows::Forms::Control* temp0 [] = {this->listBox1}; this->Controls->AddRange(temp0); this->Name = S"Form1"; this->Text = S"Form1"; this->ResumeLayout(false); } void listBox1_MeasureItem(Object* /*sender*/, MeasureItemEventArgs* e) { System::Drawing::Font* font = (dynamic_cast<ListBoxFontItem*>(listBox1->Items->Item[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 == 0 ) 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. System::Drawing::Font* font = (dynamic_cast<ListBoxFontItem*>(listBox1->Items->Item[e->Index]))->Font; e->DrawBackground(); e->Graphics->DrawString(font->Name, font, brush, RectangleF::op_Implicit(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: __gc class ListBoxFontItem { public: System::Drawing::Font* Font; ListBoxFontItem(System::Drawing::Font* f) { Font = f; } String* ToString() { return Font->Name; } }; }; [STAThread] int main() { Application::Run(new Form1()); }
[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button
in the upper-left corner of the page.
Requirements
Namespace: System.Windows.Forms
Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
See Also
MeasureItemEventArgs Members | System.Windows.Forms Namespace | ListBox | ComboBox | CheckedListBox | MenuItem | MeasureItemEventHandler