ToolboxItemCreatorCallback Delegát
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.
Poskytuje mechanismus zpětného volání, který může vytvořit ToolboxItem.
public delegate System::Drawing::Design::ToolboxItem ^ ToolboxItemCreatorCallback(System::Object ^ serializedObject, System::String ^ format);
public delegate System.Drawing.Design.ToolboxItem ToolboxItemCreatorCallback(object serializedObject, string format);
type ToolboxItemCreatorCallback = delegate of obj * string -> ToolboxItem
Public Delegate Function ToolboxItemCreatorCallback(serializedObject As Object, format As String) As ToolboxItem
Parametry
- serializedObject
- Object
Objekt, který obsahuje data pro vytvoření ToolboxItem .
- format
- String
Název datového formátu schránky, pro který ToolboxItem se má vytvořit.
Návratová hodnota
Deserializovaný ToolboxItem objekt určený parametrem serializedObject
.
Příklady
Následující příklad poskytuje komponentu IToolboxService , která používá k přidání "Text" datového formátu obslužnou rutinu nebo ToolboxItemCreatorCallback, do sady nástrojů. Delegát zpětného volání tvůrce dat předá všechna textová data vložená do panelu nástrojů a přetažená do formuláře do vlastního ToolboxItem , který vytvoří TextBox text.
#using <System.Windows.Forms.dll>
#using <System.Drawing.dll>
#using <System.dll>
using namespace System;
using namespace System::ComponentModel;
using namespace System::ComponentModel::Design;
using namespace System::Drawing;
using namespace System::Drawing::Design;
using namespace System::Windows::Forms;
using namespace System::Security::Permissions;
namespace TextDataTextBoxComponent
{
// Custom toolbox item creates a TextBox and sets its Text property
// to the constructor-specified text.
[PermissionSetAttribute(SecurityAction::Demand, Name="FullTrust")]
public ref class TextToolboxItem: public ToolboxItem
{
private:
String^ text;
delegate void SetTextMethodHandler( Control^ c, String^ text );
public:
TextToolboxItem( String^ text )
: ToolboxItem()
{
this->text = text;
}
protected:
// ToolboxItem::CreateComponentsCore to create the TextBox
// and link a method to set its Text property.
virtual array<IComponent^>^ CreateComponentsCore( IDesignerHost^ host ) override
{
TextBox^ textbox = dynamic_cast<TextBox^>(host->CreateComponent( TextBox::typeid ));
// Because the designer resets the text of the textbox, use
// a SetTextMethodHandler to set the text to the value of
// the text data.
Control^ c = dynamic_cast<Control^>(host->RootComponent);
array<Object^>^temp0 = {textbox,text};
c->BeginInvoke( gcnew SetTextMethodHandler( this, &TextToolboxItem::OnSetText ), temp0 );
array<IComponent^>^temp1 = {textbox};
return temp1;
}
private:
// Method to set the text property of a TextBox after it is initialized.
void OnSetText( Control^ c, String^ text )
{
c->Text = text;
}
};
// Component that adds a "Text" data format ToolboxItemCreatorCallback
// to the Toolbox. This component uses a custom ToolboxItem that
// creates a TextBox containing the text data.
public ref class TextDataTextBoxComponent: public Component
{
private:
bool creatorAdded;
IToolboxService^ ts;
public:
TextDataTextBoxComponent()
{
creatorAdded = false;
}
property System::ComponentModel::ISite^ Site
{
// ISite to register TextBox creator
virtual System::ComponentModel::ISite^ get() override
{
return __super::Site;
}
virtual void set( System::ComponentModel::ISite^ value ) override
{
if ( value != nullptr )
{
__super::Site = value;
if ( !creatorAdded )
AddTextTextBoxCreator();
}
else
{
if ( creatorAdded )
RemoveTextTextBoxCreator();
__super::Site = value;
}
}
}
private:
// Adds a "Text" data format creator to the toolbox that creates
// a textbox from a text fragment pasted to the toolbox.
void AddTextTextBoxCreator()
{
ts = dynamic_cast<IToolboxService^>(GetService( IToolboxService::typeid ));
if ( ts != nullptr )
{
ToolboxItemCreatorCallback^ textCreator =
gcnew ToolboxItemCreatorCallback(
this,
&TextDataTextBoxComponent::CreateTextBoxForText );
try
{
ts->AddCreator(
textCreator,
"Text",
dynamic_cast<IDesignerHost^>(GetService( IDesignerHost::typeid )) );
creatorAdded = true;
}
catch ( Exception^ ex )
{
MessageBox::Show( ex->ToString(), "Exception Information" );
}
}
}
// Removes any "Text" data format creator from the toolbox.
void RemoveTextTextBoxCreator()
{
if ( ts != nullptr )
{
ts->RemoveCreator(
"Text",
dynamic_cast<IDesignerHost^>(GetService( IDesignerHost::typeid )) );
creatorAdded = false;
}
}
// ToolboxItemCreatorCallback delegate format method to create
// the toolbox item.
ToolboxItem^ CreateTextBoxForText( Object^ serializedObject, String^ format )
{
IDataObject^ o = gcnew DataObject(dynamic_cast<IDataObject^>(serializedObject));
if( o->GetDataPresent("System::String", true) )
{
String^ toolboxText = dynamic_cast<String^>(o->GetData( "System::String", true ));
return( gcnew TextToolboxItem( toolboxText ));
}
return nullptr;
}
public:
~TextDataTextBoxComponent()
{
if ( creatorAdded )
RemoveTextTextBoxCreator();
}
};
}
using System;
using System.ComponentModel;
using System.ComponentModel.Design;
using System.Drawing;
using System.Drawing.Design;
using System.Security.Permissions;
using System.Windows.Forms;
namespace TextDataTextBoxComponent
{
// Component that adds a "Text" data format ToolboxItemCreatorCallback
// to the Toolbox. This component uses a custom ToolboxItem that
// creates a TextBox containing the text data.
public class TextDataTextBoxComponent : Component
{
private bool creatorAdded = false;
private IToolboxService ts;
public TextDataTextBoxComponent()
{
}
// ISite override to register TextBox creator
public override System.ComponentModel.ISite Site
{
get
{
return base.Site;
}
set
{
if( value != null )
{
base.Site = value;
if (!creatorAdded)
{
AddTextTextBoxCreator();
}
}
else
{
if (creatorAdded)
{
RemoveTextTextBoxCreator();
}
base.Site = value;
}
}
}
// Adds a "Text" data format creator to the toolbox that creates
// a textbox from a text fragment pasted to the toolbox.
private void AddTextTextBoxCreator()
{
ts = (IToolboxService)GetService(typeof(IToolboxService));
if (ts != null)
{
ToolboxItemCreatorCallback textCreator =
new ToolboxItemCreatorCallback(this.CreateTextBoxForText);
try
{
ts.AddCreator(
textCreator,
"Text",
(IDesignerHost)GetService(typeof(IDesignerHost)));
creatorAdded = true;
}
catch(Exception ex)
{
MessageBox.Show(
ex.ToString(),
"Exception Information");
}
}
}
// Removes any "Text" data format creator from the toolbox.
private void RemoveTextTextBoxCreator()
{
if (ts != null)
{
ts.RemoveCreator(
"Text",
(IDesignerHost)GetService(typeof(IDesignerHost)));
creatorAdded = false;
}
}
// ToolboxItemCreatorCallback delegate format method to create
// the toolbox item.
private ToolboxItem CreateTextBoxForText(
object serializedObject,
string format)
{
DataObject o = new DataObject((IDataObject)serializedObject);
string[] formats = o.GetFormats();
if (o.GetDataPresent("System.String", true))
{
string toolboxText = (string)(o.GetData("System.String", true));
return (new TextToolboxItem(toolboxText));
}
return null;
}
protected override void Dispose(bool disposing)
{
if (creatorAdded)
{
RemoveTextTextBoxCreator();
}
}
}
// Custom toolbox item creates a TextBox and sets its Text property
// to the constructor-specified text.
public class TextToolboxItem : ToolboxItem
{
private string text;
private delegate void SetTextMethodHandler(Control c, string text);
public TextToolboxItem(string text) : base()
{
this.text = text;
}
// ToolboxItem.CreateComponentsCore override to create the TextBox
// and link a method to set its Text property.
protected override IComponent[] CreateComponentsCore(IDesignerHost host)
{
System.Windows.Forms.TextBox textbox =
(TextBox)host.CreateComponent(typeof(TextBox));
// Because the designer resets the text of the textbox, use
// a SetTextMethodHandler to set the text to the value of
// the text data.
Control c = host.RootComponent as Control;
c.BeginInvoke(
new SetTextMethodHandler(OnSetText),
new object[] {textbox, text});
return new System.ComponentModel.IComponent[] { textbox };
}
// Method to set the text property of a TextBox after it is initialized.
private void OnSetText(Control c, string text)
{
c.Text = text;
}
}
}
Imports System.ComponentModel
Imports System.ComponentModel.Design
Imports System.Drawing
Imports System.Drawing.Design
Imports System.Security.Permissions
Imports System.Windows.Forms
' Component that adds a "Text" data format ToolboxItemCreatorCallback
' to the Toolbox. This component uses a custom ToolboxItem that
' creates a TextBox containing the text data.
<PermissionSetAttribute(SecurityAction.Demand, Name:="FullTrust")> _
Public Class TextDataTextBoxComponent
Inherits System.ComponentModel.Component
Private creatorAdded As Boolean = False
Private ts As IToolboxService
Public Sub New()
End Sub
' ISite override to register TextBox creator
Public Overrides Property Site() As System.ComponentModel.ISite
Get
Return MyBase.Site
End Get
Set(ByVal Value As System.ComponentModel.ISite)
If (Value IsNot Nothing) Then
MyBase.Site = Value
If Not creatorAdded Then
AddTextTextBoxCreator()
End If
Else
If creatorAdded Then
RemoveTextTextBoxCreator()
End If
MyBase.Site = Value
End If
End Set
End Property
' Adds a "Text" data format creator to the toolbox that creates
' a textbox from a text fragment pasted to the toolbox.
Private Sub AddTextTextBoxCreator()
ts = CType(GetService(GetType(IToolboxService)), IToolboxService)
If (ts IsNot Nothing) Then
Dim textCreator As _
New ToolboxItemCreatorCallback(AddressOf Me.CreateTextBoxForText)
Try
ts.AddCreator( _
textCreator, _
"Text", _
CType(GetService(GetType(IDesignerHost)), IDesignerHost))
creatorAdded = True
Catch ex As Exception
MessageBox.Show(ex.ToString(), "Exception Information")
End Try
End If
End Sub
' Removes any "Text" data format creator from the toolbox.
Private Sub RemoveTextTextBoxCreator()
If (ts IsNot Nothing) Then
ts.RemoveCreator( _
"Text", _
CType(GetService(GetType(IDesignerHost)), IDesignerHost))
creatorAdded = False
End If
End Sub
' ToolboxItemCreatorCallback delegate format method to create
' the toolbox item.
Private Function CreateTextBoxForText( _
ByVal serializedObject As Object, _
ByVal format As String) As ToolboxItem
Dim o As New DataObject(CType(serializedObject, IDataObject))
Dim formats As String() = o.GetFormats()
If o.GetDataPresent("System.String", True) Then
Return New TextToolboxItem(CStr(o.GetData("System.String", True)))
End If
Return Nothing
End Function
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If creatorAdded Then
RemoveTextTextBoxCreator()
End If
End Sub
End Class
' Custom toolbox item creates a TextBox and sets its Text property
' to the constructor-specified text.
<PermissionSetAttribute(SecurityAction.Demand, Name:="FullTrust")> _
Public Class TextToolboxItem
Inherits System.Drawing.Design.ToolboxItem
Private [text] As String
Delegate Sub SetTextMethodHandler( _
ByVal c As Control, _
ByVal [text] As String)
Public Sub New(ByVal [text] As String)
Me.text = [text]
End Sub
' ToolboxItem.CreateComponentsCore override to create the TextBox
' and link a method to set its Text property.
<PermissionSetAttribute(SecurityAction.Demand, Name:="FullTrust")> _
Protected Overrides Function CreateComponentsCore(ByVal host As IDesignerHost) As IComponent()
Dim textbox As TextBox = CType(host.CreateComponent(GetType(TextBox)), TextBox)
' Because the designer resets the text of the textbox, use
' a SetTextMethodHandler to set the text to the value of
' the text data.
Dim c As Control = host.RootComponent
c.BeginInvoke( _
New SetTextMethodHandler(AddressOf OnSetText), _
New Object() {textbox, [text]})
Return New System.ComponentModel.IComponent() {textbox}
End Function
' Method to set the text property of a TextBox after it is initialized.
Private Sub OnSetText(ByVal c As Control, ByVal [text] As String)
c.Text = [text]
End Sub
End Class
Poznámky
Můžete implementovat metodu tvůrce položek panelu nástrojů s podpisem metody, který odpovídá podpisu metody tohoto typu delegáta, který vytvoří položku panelu nástrojů z libovolného objektu konkrétního datového formátu schránky umístěného na panelu nástrojů. Můžete například navrhnout tvůrce položek na panelu nástrojů, který vytvoří objekt pro TextBox uložení textu vloženého do sady nástrojů ze schránky. AddCreator Pomocí metody IToolboxService můžete přidat obslužnou rutinu ToolboxItemCreatorCallback události pro konkrétní datový typ do sady nástrojů. Parametr serializedObject
obsahuje datový objekt.
Při vytváření delegáta ToolboxItemCreatorCallback identifikujete metodu, která bude zpracovávat událost. Pokud chcete událost přidružit k obslužné rutině události, přidejte do události instanci delegáta. Obslužná rutina události je volána při každém výskytu události, dokud neodeberete delegáta. Další informace o delegátech obslužných rutin událostí najdete v tématu Zpracování a vyvolávání událostí.
Metody rozšíření
GetMethodInfo(Delegate) |
Získá objekt, který představuje metodu reprezentovanou zadaným delegátem. |