ToolTip.Draw Událost
Definice
Důležité
Některé informace platí pro předběžně vydaný produkt, který se může zásadně změnit, než ho výrobce nebo autor vydá. Microsoft neposkytuje žádné záruky, výslovné ani předpokládané, týkající se zde uváděných informací.
public:
event System::Windows::Forms::DrawToolTipEventHandler ^ Draw;
public event System.Windows.Forms.DrawToolTipEventHandler Draw;
public event System.Windows.Forms.DrawToolTipEventHandler? Draw;
member this.Draw : System.Windows.Forms.DrawToolTipEventHandler
Public Custom Event Draw As DrawToolTipEventHandler
Event Type
Příklady
Následující příklad kódu ukazuje, jak vlastní nakreslit ToolTip. Příklad vytvoří a přidruží ToolTip ho ke třem Button ovládacím prvkům umístěným na Form. Příklad nastaví OwnerDraw vlastnost na true
a zpracuje Draw událost. V obslužné rutině DrawToolTip události je vlastní nakresleno odlišně v závislosti na tom, pro jaké tlačítko ToolTip se zobrazuje, jak je uvedeno ve DrawToolTipEventArgs.AssociatedControl vlastnosti.
#using <System.dll>
#using <System.Windows.Forms.dll>
#using <System.Drawing.dll>
using namespace System;
using namespace System::Drawing;
using namespace System::Windows::Forms;
using namespace System::Windows::Forms::VisualStyles;
// Form for the ToolTip example.
public ref class ToolTipExampleForm: public System::Windows::Forms::Form
{
private:
System::Windows::Forms::ToolTip^ toolTip1;
System::Windows::Forms::Button^ button1;
System::Windows::Forms::Button^ button2;
System::Windows::Forms::Button^ button3;
public:
ToolTipExampleForm()
{
// Create the ToolTip and set initial values.
this->toolTip1 = gcnew System::Windows::Forms::ToolTip;
this->toolTip1->AutoPopDelay = 5000;
this->toolTip1->InitialDelay = 500;
this->toolTip1->OwnerDraw = true;
this->toolTip1->ReshowDelay = 10;
this->toolTip1->Draw += gcnew DrawToolTipEventHandler( this, &ToolTipExampleForm::toolTip1_Draw );
// Create button1 and set initial values.
this->button1 = gcnew System::Windows::Forms::Button;
this->button1->Location = System::Drawing::Point( 8, 8 );
this->button1->Text = "Button 1";
this->toolTip1->SetToolTip( this->button1, "Button1 tip text" );
// Create button2 and set initial values.
this->button2 = gcnew System::Windows::Forms::Button;
this->button2->Location = System::Drawing::Point( 8, 32 );
this->button2->Text = "Button 2";
this->toolTip1->SetToolTip( this->button2, "Button2 tip text" );
// Create button3 and set initial values.
this->button3 = gcnew System::Windows::Forms::Button;
this->button3->Location = System::Drawing::Point( 8, 56 );
this->button3->Text = "Button 3";
this->toolTip1->SetToolTip( this->button3, "Button3 tip text" );
// Set up the Form.
array<Control^>^temp0 = {this->button1,this->button2,this->button3};
this->Controls->AddRange( temp0 );
this->Text = "owner drawn ToolTip example";
}
protected:
~ToolTipExampleForm()
{
if ( toolTip1 != nullptr )
{
delete toolTip1;
}
}
// Handles drawing the ToolTip.
private:
void toolTip1_Draw( System::Object^ /*sender*/, System::Windows::Forms::DrawToolTipEventArgs^ e )
{
// Draw the ToolTip differently depending on which
// control this ToolTip is for.
// Draw a custom 3D border if the ToolTip is for button1.
if ( e->AssociatedControl == button1 )
{
// Draw the standard background.
e->DrawBackground();
// Draw the custom border to appear 3-dimensional.
array<Point>^ temp1 = {Point(0,e->Bounds.Height - 1),Point(0,0),Point(e->Bounds.Width - 1,0)};
e->Graphics->DrawLines( SystemPens::ControlLightLight, temp1 );
array<Point>^ temp2 = {Point(0,e->Bounds.Height - 1),Point(e->Bounds.Width - 1,e->Bounds.Height - 1),Point(e->Bounds.Width - 1,0)};
e->Graphics->DrawLines( SystemPens::ControlDarkDark, temp2 );
// Specify custom text formatting flags.
TextFormatFlags sf = static_cast<TextFormatFlags>(TextFormatFlags::VerticalCenter | TextFormatFlags::HorizontalCenter | TextFormatFlags::NoFullWidthCharacterBreak);
// Draw the standard text with customized formatting options.
e->DrawText( sf );
}
// Draw a custom background and text if the ToolTip is for button2.
else
// Draw a custom background and text if the ToolTip is for button2.
if ( e->AssociatedControl == button2 )
{
// Draw the custom background.
e->Graphics->FillRectangle( SystemBrushes::ActiveCaption, e->Bounds );
// Draw the standard border.
e->DrawBorder();
// Draw the custom text.
// The using block will dispose the StringFormat automatically.
StringFormat^ sf = gcnew StringFormat;
try
{
sf->Alignment = StringAlignment::Center;
sf->LineAlignment = StringAlignment::Center;
sf->HotkeyPrefix = System::Drawing::Text::HotkeyPrefix::None;
sf->FormatFlags = StringFormatFlags::NoWrap;
System::Drawing::Font^ f = gcnew System::Drawing::Font( "Tahoma",9 );
try
{
e->Graphics->DrawString( e->ToolTipText, f, SystemBrushes::ActiveCaptionText, e->Bounds, sf );
}
finally
{
if ( f )
delete safe_cast<IDisposable^>(f);
}
}
finally
{
if ( sf )
delete safe_cast<IDisposable^>(sf);
}
}
// Draw the ToolTip using default values if the ToolTip is for button3.
else if ( e->AssociatedControl == button3 )
{
e->DrawBackground();
e->DrawBorder();
e->DrawText();
}
}
};
// The main entry point for the application.
[STAThread]
int main()
{
Application::Run( gcnew ToolTipExampleForm );
}
using System;
using System.Drawing;
using System.Windows.Forms;
using System.Windows.Forms.VisualStyles;
namespace ToolTipExample
{
// Form for the ToolTip example.
public class ToolTipExampleForm : System.Windows.Forms.Form
{
private System.Windows.Forms.ToolTip toolTip1;
private System.Windows.Forms.Button button1;
private System.Windows.Forms.Button button2;
private System.Windows.Forms.Button button3;
public ToolTipExampleForm()
{
// Create the ToolTip and set initial values.
this.toolTip1 = new System.Windows.Forms.ToolTip();
this.toolTip1.AutoPopDelay = 5000;
this.toolTip1.InitialDelay = 500;
this.toolTip1.OwnerDraw = true;
this.toolTip1.ReshowDelay = 10;
this.toolTip1.Draw += new DrawToolTipEventHandler(this.toolTip1_Draw);
this.toolTip1.Popup += new PopupEventHandler(toolTip1_Popup);
// Create button1 and set initial values.
this.button1 = new System.Windows.Forms.Button();
this.button1.Location = new System.Drawing.Point(8, 8);
this.button1.Text = "Button 1";
this.toolTip1.SetToolTip(this.button1, "Button1 tip text");
// Create button2 and set initial values.
this.button2 = new System.Windows.Forms.Button();
this.button2.Location = new System.Drawing.Point(8, 32);
this.button2.Text = "Button 2";
this.toolTip1.SetToolTip(this.button2, "Button2 tip text");
// Create button3 and set initial values.
this.button3 = new System.Windows.Forms.Button();
this.button3.Location = new System.Drawing.Point(8, 56);
this.button3.Text = "Button 3";
this.toolTip1.SetToolTip(this.button3, "Button3 tip text");
// Set up the Form.
this.Controls.AddRange(new Control[] {
this.button1, this.button2, this.button3
});
this.Text = "owner drawn ToolTip example";
}
// Clean up any resources being used.
protected override void Dispose(bool disposing)
{
if (disposing)
{
toolTip1.Dispose();
}
base.Dispose(disposing);
}
// The main entry point for the application.
[STAThread]
static void Main()
{
Application.Run(new ToolTipExampleForm());
}
// Determines the correct size for the button2 ToolTip.
private void toolTip1_Popup(object sender, PopupEventArgs e)
{
if (e.AssociatedControl == button2)
{
using (Font f = new Font("Tahoma", 9))
{
e.ToolTipSize = TextRenderer.MeasureText(
toolTip1.GetToolTip(e.AssociatedControl), f);
}
}
}
// Handles drawing the ToolTip.
private void toolTip1_Draw(System.Object sender,
System.Windows.Forms.DrawToolTipEventArgs e)
{
// Draw the ToolTip differently depending on which
// control this ToolTip is for.
// Draw a custom 3D border if the ToolTip is for button1.
if (e.AssociatedControl == button1)
{
// Draw the standard background.
e.DrawBackground();
// Draw the custom border to appear 3-dimensional.
e.Graphics.DrawLines(SystemPens.ControlLightLight, new Point[] {
new Point (0, e.Bounds.Height - 1),
new Point (0, 0),
new Point (e.Bounds.Width - 1, 0)
});
e.Graphics.DrawLines(SystemPens.ControlDarkDark, new Point[] {
new Point (0, e.Bounds.Height - 1),
new Point (e.Bounds.Width - 1, e.Bounds.Height - 1),
new Point (e.Bounds.Width - 1, 0)
});
// Specify custom text formatting flags.
TextFormatFlags sf = TextFormatFlags.VerticalCenter |
TextFormatFlags.HorizontalCenter |
TextFormatFlags.NoFullWidthCharacterBreak;
// Draw the standard text with customized formatting options.
e.DrawText(sf);
}
// Draw a custom background and text if the ToolTip is for button2.
else if (e.AssociatedControl == button2)
{
// Draw the custom background.
e.Graphics.FillRectangle(SystemBrushes.ActiveCaption, e.Bounds);
// Draw the standard border.
e.DrawBorder();
// Draw the custom text.
// The using block will dispose the StringFormat automatically.
using (StringFormat sf = new StringFormat())
{
sf.Alignment = StringAlignment.Center;
sf.LineAlignment = StringAlignment.Center;
sf.HotkeyPrefix = System.Drawing.Text.HotkeyPrefix.None;
sf.FormatFlags = StringFormatFlags.NoWrap;
using (Font f = new Font("Tahoma", 9))
{
e.Graphics.DrawString(e.ToolTipText, f,
SystemBrushes.ActiveCaptionText, e.Bounds, sf);
}
}
}
// Draw the ToolTip using default values if the ToolTip is for button3.
else if (e.AssociatedControl == button3)
{
e.DrawBackground();
e.DrawBorder();
e.DrawText();
}
}
}
}
Imports System.Drawing
Imports System.Windows.Forms
Imports System.Windows.Forms.VisualStyles
Public Module ToolTipExampleApp
' The main entry point for the application.
<STAThread()> _
Sub Main()
Application.Run(New ToolTipExampleForm)
End Sub
End Module
' Form for the ToolTip example.
Public Class ToolTipExampleForm
Inherits System.Windows.Forms.Form
Private WithEvents toolTip1 As System.Windows.Forms.ToolTip
Private WithEvents button1 As System.Windows.Forms.Button
Private WithEvents button2 As System.Windows.Forms.Button
Private WithEvents button3 As System.Windows.Forms.Button
Public Sub New()
' Create the ToolTip and set initial values.
Me.toolTip1 = New System.Windows.Forms.ToolTip
Me.toolTip1.AutoPopDelay = 5000
Me.toolTip1.InitialDelay = 500
Me.toolTip1.OwnerDraw = True
Me.toolTip1.ReshowDelay = 10
' Create button1 and set initial values.
Me.button1 = New System.Windows.Forms.Button
Me.button1.Location = New System.Drawing.Point(8, 8)
Me.button1.Text = "Button 1"
Me.toolTip1.SetToolTip(Me.button1, "Button1 tip text")
' Create button2 and set initial values.
Me.button2 = New System.Windows.Forms.Button
Me.button2.Location = New System.Drawing.Point(8, 32)
Me.button2.Text = "Button 2"
Me.toolTip1.SetToolTip(Me.button2, "Button2 tip text")
' Create button3 and set initial values.
Me.button3 = New System.Windows.Forms.Button
Me.button3.Location = New System.Drawing.Point(8, 56)
Me.button3.Text = "Button 3"
Me.toolTip1.SetToolTip(Me.button3, "Button3 tip text")
' Set up the Form.
Me.Controls.AddRange(New Control() {Me.button1, _
Me.button2, _
Me.button3})
Me.Text = "owner drawn ToolTip example"
End Sub
' Clean up any resources being used.
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If (disposing) Then
toolTip1.Dispose()
End If
MyBase.Dispose(disposing)
End Sub
' Determines the correct size for the button2 ToolTip.
Private Sub toolTip1_Popup(ByVal sender As System.Object, _
ByVal e As PopupEventArgs) Handles toolTip1.Popup
If e.AssociatedControl Is button2 Then
Dim f As New Font("Tahoma", 9)
Try
e.ToolTipSize = TextRenderer.MeasureText( _
toolTip1.GetToolTip(e.AssociatedControl), f)
Finally
f.Dispose()
End Try
End If
End Sub
' Handles drawing the ToolTip.
Private Sub toolTip1_Draw(ByVal sender As System.Object, _
ByVal e As DrawToolTipEventArgs) Handles toolTip1.Draw
' Draw the ToolTip differently depending on which
' control this ToolTip is for.
' Draw a custom 3D border if the ToolTip is for button1.
If (e.AssociatedControl Is button1) Then
' Draw the standard background.
e.DrawBackground()
' Draw the custom border to appear 3-dimensional.
e.Graphics.DrawLines( _
SystemPens.ControlLightLight, New Point() { _
New Point(0, e.Bounds.Height - 1), _
New Point(0, 0), _
New Point(e.Bounds.Width - 1, 0)})
e.Graphics.DrawLines( _
SystemPens.ControlDarkDark, New Point() { _
New Point(0, e.Bounds.Height - 1), _
New Point(e.Bounds.Width - 1, e.Bounds.Height - 1), _
New Point(e.Bounds.Width - 1, 0)})
' Specify custom text formatting flags.
Dim sf As TextFormatFlags = TextFormatFlags.VerticalCenter Or _
TextFormatFlags.HorizontalCenter Or _
TextFormatFlags.NoFullWidthCharacterBreak
' Draw standard text with customized formatting options.
e.DrawText(sf)
ElseIf (e.AssociatedControl Is button2) Then
' Draw a custom background and text if the ToolTip is for button2.
' Draw the custom background.
e.Graphics.FillRectangle(SystemBrushes.ActiveCaption, e.Bounds)
' Draw the standard border.
e.DrawBorder()
' Draw the custom text.
Dim sf As StringFormat = New StringFormat
Try
sf.Alignment = StringAlignment.Center
sf.LineAlignment = StringAlignment.Center
sf.HotkeyPrefix = System.Drawing.Text.HotkeyPrefix.None
sf.FormatFlags = StringFormatFlags.NoWrap
Dim f As Font = New Font("Tahoma", 9)
Try
e.Graphics.DrawString(e.ToolTipText, f, _
SystemBrushes.ActiveCaptionText, _
RectangleF.op_Implicit(e.Bounds), sf)
Finally
f.Dispose()
End Try
Finally
sf.Dispose()
End Try
ElseIf (e.AssociatedControl Is button3) Then
' Draw the ToolTip using default values if the ToolTip is for button3.
e.DrawBackground()
e.DrawBorder()
e.DrawText()
End If
End Sub
End Class
Poznámky
Draw Pomocí události můžete přizpůsobit vzhled objektu ToolTip.
Událost Draw je vyvolána ToolTip třídou, když ToolTip je vykreslen a ToolTip.OwnerDraw hodnota vlastnosti je true
a IsBalloon vlastnost je false
. Třída DrawToolTipEventArgs obsahuje všechny informace potřebné k vykreslení objektu ToolTip, včetně textu popisku, objektu Rectanglea objektu Graphics , na kterém se má výkres provést. Pokud chcete přizpůsobit vzhled popisu, použijte Rectangle k určení hranic popisu a objektu Graphics k provedení přizpůsobeného výkresu. Můžete zvýšit hranice ToolTip před zobrazením události zpracováním Popup události.
Další informace o zpracování událostí najdete v tématu Zpracování a vyvolávání událostí.