ListView.OnColumnClick(ColumnClickEventArgs) Metodo

Riferimento

Definizione

Spazio dei nomi:: System.Windows.Forms

Assembly:: System.Windows.Forms.dll

Importante

Alcune informazioni sono relative alla release non definitiva del prodotto, che potrebbe subire modifiche significative prima della release definitiva. Microsoft non riconosce alcuna garanzia, espressa o implicita, in merito alle informazioni qui fornite.

Genera l'evento ColumnClick.

protected:
 virtual void OnColumnClick(System::Windows::Forms::ColumnClickEventArgs ^ e);

protected virtual void OnColumnClick (System.Windows.Forms.ColumnClickEventArgs e);

abstract member OnColumnClick : System.Windows.Forms.ColumnClickEventArgs -> unit
override this.OnColumnClick : System.Windows.Forms.ColumnClickEventArgs -> unit

Protected Overridable Sub OnColumnClick (e As ColumnClickEventArgs)

Parametri

e: ColumnClickEventArgs

Oggetto ColumnClickEventArgs che contiene i dati dell'evento.

Esempio

Nell'esempio di codice seguente viene creato un modulo che contiene un ListView controllo che ordina manualmente gli elementi quando viene fatto clic su una colonna nel ListView controllo. L'esempio definisce una classe denominata ListViewItemComparer che implementa l'interfaccia che esegue il System.Collections.IComparer ListViewItem confronto. Nell'esempio viene creata un'istanza di ListViewItemComparer e viene usata per impostare la ListViewItemSorter proprietà del ListView controllo. La Sort chiamata al metodo nel ColumnClick gestore eventi usa i metodi definiti in ListViewItemComparer per eseguire il tipo di elementi, in base alla colonna su cui viene fatto clic.

#using <System.dll>
#using <System.Drawing.dll>
#using <System.Windows.Forms.dll>

using namespace System;
using namespace System::Windows::Forms;
using namespace System::Drawing;
using namespace System::Collections;

// Implements the manual sorting of items by columns.
ref class ListViewItemComparer: public IComparer
{
private:
   int col;

public:
   ListViewItemComparer()
   {
      col = 0;
   }

   ListViewItemComparer( int column )
   {
      col = column;
   }

   virtual int Compare( Object^ x, Object^ y )
   {
      return String::Compare( (dynamic_cast<ListViewItem^>(x))->SubItems[ col ]->Text,
                              (dynamic_cast<ListViewItem^>(y))->SubItems[ col ]->Text );
   }
};

public ref class ListViewSortForm: public Form
{
private:
   ListView^ listView1;

public:
   ListViewSortForm()
   {
      // Create ListView items to add to the control.
      array<String^>^temp0 = {"Banana","a","b","c"};
      ListViewItem^ listViewItem1 = gcnew ListViewItem( temp0,-1,Color::Empty,Color::Yellow,nullptr );
      array<String^>^temp1 = {"Cherry","v","g","t"};
      ListViewItem^ listViewItem2 = gcnew ListViewItem( temp1,-1,Color::Empty,Color::Red,
                 gcnew System::Drawing::Font( "Microsoft Sans Serif",8.25F,FontStyle::Regular,GraphicsUnit::Point,0 ) );
      array<String^>^temp2 = {"Apple","h","j","n"};
      ListViewItem^ listViewItem3 = gcnew ListViewItem( temp2,-1,Color::Empty,Color::Lime,nullptr );
      array<String^>^temp3 = {"Pear","y","u","i"};
      ListViewItem^ listViewItem4 = gcnew ListViewItem( temp3,-1,Color::Empty,Color::FromArgb( 192, 128, 156 ),nullptr );

      //Initialize the ListView control and add columns to it.
      this->listView1 = gcnew ListView;

      // Set the initial sorting type for the ListView.
      this->listView1->Sorting = SortOrder::None;

      // Disable automatic sorting to enable manual sorting.
      this->listView1->View = View::Details;

      // Add columns and set their text.
      this->listView1->Columns->Add( gcnew ColumnHeader );
      this->listView1->Columns[ 0 ]->Text = "Column 1";
      this->listView1->Columns[ 0 ]->Width = 100;
      listView1->Columns->Add( gcnew ColumnHeader );
      listView1->Columns[ 1 ]->Text = "Column 2";
      listView1->Columns->Add( gcnew ColumnHeader );
      listView1->Columns[ 2 ]->Text = "Column 3";
      listView1->Columns->Add( gcnew ColumnHeader );
      listView1->Columns[ 3 ]->Text = "Column 4";

      // Suspend control logic until form is done configuring form.
      this->SuspendLayout();

      // Add Items to the ListView control.
      array<ListViewItem^>^temp4 = {listViewItem1,listViewItem2,listViewItem3,listViewItem4};
      this->listView1->Items->AddRange( temp4 );

      // Set the location and size of the ListView control.
      this->listView1->Location = Point(10,10);
      this->listView1->Name = "listView1";
      this->listView1->Size = System::Drawing::Size( 300, 100 );
      this->listView1->TabIndex = 0;

      // Enable editing of the items in the ListView.
      this->listView1->LabelEdit = true;

      // Connect the ListView::ColumnClick event to the ColumnClick event handler.
      this->listView1->ColumnClick += gcnew ColumnClickEventHandler( this, &ListViewSortForm::ColumnClick );

      // Initialize the form.
      this->ClientSize = System::Drawing::Size( 400, 400 );
      array<Control^>^temp5 = {this->listView1};
      this->Controls->AddRange( temp5 );
      this->Name = "ListViewSortForm";
      this->Text = "Sorted ListView Control";

      // Resume lay[Out] of* the form.
      this->ResumeLayout( false );
   }

private:

   // ColumnClick event handler.
   void ColumnClick( Object^ /*o*/, ColumnClickEventArgs^ e )
   {
      // Set the ListViewItemSorter property to a new ListViewItemComparer 
      // object. Setting this property immediately sorts the 
      // ListView using the ListViewItemComparer object.
      this->listView1->ListViewItemSorter = gcnew ListViewItemComparer( e->Column );
   }
};

[System::STAThreadAttribute]
int main()
{
   Application::Run( gcnew ListViewSortForm );
}

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

namespace ListViewSortFormNamespace
{

    public class ListViewSortForm : Form
    {
        private ListView listView1;
       
        public ListViewSortForm()
        {
            // Create ListView items to add to the control.
            ListViewItem listViewItem1 = new ListViewItem(new string[] {"Banana","a","b","c"}, -1, Color.Empty, Color.Yellow, null);
            ListViewItem listViewItem2 = new ListViewItem(new string[] {"Cherry","v","g","t"}, -1, Color.Empty, Color.Red, new Font("Microsoft Sans Serif", 8.25F, FontStyle.Regular, GraphicsUnit.Point, ((System.Byte)(0))));
            ListViewItem listViewItem3 = new ListViewItem(new string[] {"Apple","h","j","n"}, -1, Color.Empty, Color.Lime, null);
            ListViewItem listViewItem4 = new ListViewItem(new string[] {"Pear","y","u","i"}, -1, Color.Empty, Color.FromArgb(((System.Byte)(192)), ((System.Byte)(128)), ((System.Byte)(156))), null);
     
            //Initialize the ListView control and add columns to it.
            this.listView1 = new ListView();

            // Set the initial sorting type for the ListView.
            this.listView1.Sorting = SortOrder.None;
            // Disable automatic sorting to enable manual sorting.
            this.listView1.View = View.Details;
            // Add columns and set their text.
            this.listView1.Columns.Add(new ColumnHeader());
            this.listView1.Columns[0].Text = "Column 1";
            this.listView1.Columns[0].Width = 100;
            listView1.Columns.Add(new ColumnHeader());
            listView1.Columns[1].Text = "Column 2";
            listView1.Columns.Add(new ColumnHeader());
            listView1.Columns[2].Text = "Column 3";
            listView1.Columns.Add(new ColumnHeader());
            listView1.Columns[3].Text = "Column 4";
            // Suspend control logic until form is done configuring form.
            this.SuspendLayout();
            // Add Items to the ListView control.
            this.listView1.Items.AddRange(new ListViewItem[] {listViewItem1,
                listViewItem2,
                listViewItem3,
                listViewItem4});
            // Set the location and size of the ListView control.
            this.listView1.Location = new Point(10, 10);
            this.listView1.Name = "listView1";
            this.listView1.Size = new Size(300, 100);
            this.listView1.TabIndex = 0;
            // Enable editing of the items in the ListView.
            this.listView1.LabelEdit = true;
            // Connect the ListView.ColumnClick event to the ColumnClick event handler.
            this.listView1.ColumnClick += new ColumnClickEventHandler(ColumnClick);
            
            // Initialize the form.
            this.ClientSize = new Size(400, 400);
            this.Controls.AddRange(new Control[] {this.listView1});
            this.Name = "ListViewSortForm";
            this.Text = "Sorted ListView Control";
            // Resume layout of the form.
            this.ResumeLayout(false);
        }

        // ColumnClick event handler.
        private void ColumnClick(object o, ColumnClickEventArgs e)
        {
            // Set the ListViewItemSorter property to a new ListViewItemComparer 
            // object. Setting this property immediately sorts the 
            // ListView using the ListViewItemComparer object.
            this.listView1.ListViewItemSorter = new ListViewItemComparer(e.Column);
        }

        [System.STAThreadAttribute()]
        public static void Main()
        {
            Application.Run(new ListViewSortForm());
        }
    }

    // Implements the manual sorting of items by columns.
    class ListViewItemComparer : IComparer
    {
        private int col;
        public ListViewItemComparer()
        {
            col = 0;
        }
        public ListViewItemComparer(int column)
        {
            col = column;
        }
        public int Compare(object x, object y)
        {
            return String.Compare(((ListViewItem)x).SubItems[col].Text, ((ListViewItem)y).SubItems[col].Text);
        }
    }
}

Imports System.Windows.Forms
Imports System.Drawing
Imports System.Collections


Namespace ListViewSortFormNamespace

    Public Class ListViewSortForm
        Inherits Form

        Private listView1 As ListView

        Public Sub New()
            ' Create ListView items to add to the control.
            Dim listViewItem1 As New ListViewItem(New String() {"Banana", "a", "b", "c"}, -1, Color.Empty, Color.Yellow, Nothing)
            Dim listViewItem2 As New ListViewItem(New String() {"Cherry", "v", "g", "t"}, -1, Color.Empty, Color.Red, New Font("Microsoft Sans Serif", 8.25F, FontStyle.Regular, GraphicsUnit.Point, CType(0, System.Byte)))
            Dim listViewItem3 As New ListViewItem(New String() {"Apple", "h", "j", "n"}, -1, Color.Empty, Color.Lime, Nothing)
            Dim listViewItem4 As New ListViewItem(New String() {"Pear", "y", "u", "i"}, -1, Color.Empty, Color.FromArgb(CType(192, System.Byte), CType(128, System.Byte), CType(156, System.Byte)), Nothing)

            'Initialize the ListView control and add columns to it.
            Me.listView1 = New ListView

            ' Set the initial sorting type for the ListView.
            Me.listView1.Sorting = SortOrder.None
            ' Disable automatic sorting to enable manual sorting.
            Me.listView1.View = View.Details
            ' Add columns and set their text.
            Me.listView1.Columns.Add(New ColumnHeader)
            Me.listView1.Columns(0).Text = "Column 1"
            Me.listView1.Columns(0).Width = 100
            listView1.Columns.Add(New ColumnHeader)
            listView1.Columns(1).Text = "Column 2"
            listView1.Columns.Add(New ColumnHeader)
            listView1.Columns(2).Text = "Column 3"
            listView1.Columns.Add(New ColumnHeader)
            listView1.Columns(3).Text = "Column 4"
            ' Suspend control logic until form is done configuring form.
            Me.SuspendLayout()
            ' Add Items to the ListView control.
            Me.listView1.Items.AddRange(New ListViewItem() {listViewItem1, listViewItem2, listViewItem3, listViewItem4})
            ' Set the location and size of the ListView control.
            Me.listView1.Location = New Point(10, 10)
            Me.listView1.Name = "listView1"
            Me.listView1.Size = New Size(300, 100)
            Me.listView1.TabIndex = 0
            ' Enable editing of the items in the ListView.
            Me.listView1.LabelEdit = True
            ' Connect the ListView.ColumnClick event to the ColumnClick event handler.
            AddHandler Me.listView1.ColumnClick, AddressOf ColumnClick

            ' Initialize the form.
            Me.ClientSize = New Size(400, 400)
            Me.Controls.AddRange(New Control() {Me.listView1})
            Me.Name = "ListViewSortForm"
            Me.Text = "Sorted ListView Control"
            ' Resume layout of the form.
            Me.ResumeLayout(False)
        End Sub


        ' ColumnClick event handler.
        Private Sub ColumnClick(ByVal o As Object, ByVal e As ColumnClickEventArgs)
            ' Set the ListViewItemSorter property to a new ListViewItemComparer 
            ' object. Setting this property immediately sorts the 
            ' ListView using the ListViewItemComparer object.
            Me.listView1.ListViewItemSorter = New ListViewItemComparer(e.Column)
        End Sub

    End Class

    ' Implements the manual sorting of items by columns.
    Class ListViewItemComparer
        Implements IComparer

        Private col As Integer

        Public Sub New()
            col = 0
        End Sub

        Public Sub New(ByVal column As Integer)
            col = column
        End Sub

        Public Function Compare(ByVal x As Object, ByVal y As Object) As Integer _
           Implements IComparer.Compare
            Return [String].Compare(CType(x, ListViewItem).SubItems(col).Text, CType(y, ListViewItem).SubItems(col).Text)
        End Function
    End Class
End Namespace

Commenti

Quando viene generato un evento, il gestore dell'evento viene richiamato tramite un delegato. Per altre informazioni, vedere la gestione e generazione di eventi.

Il metodo OnColumnClick consente inoltre alle classi derivate di gestire l'evento senza associare un delegato. È la tecnica consigliata per la gestione dell'evento in una classe derivata.

Note per gli eredi

Quando si esegue l'override di OnColumnClick(ColumnClickEventArgs) in una classe derivata, verificare di chiamare il metodo OnColumnClick(ColumnClickEventArgs) della classe di base in modo che i delegati registrati ricevano l'evento.

Si applica a