TrackBar (Clase) (System.Windows.Forms)

Cambiar vista:

Clásica

Ligera

Sin script

Comentario del sitio

Biblioteca de clases de .NET Framework

TrackBar (Clase)

Actualización: noviembre 2007

Representa una barra de seguimiento estándar de Windows.

Espacio de nombres: System.Windows.Forms
Ensamblado: System.Windows.Forms (en System.Windows.Forms.dll)

Sintaxis

Visual Basic (Declaración)

<ComVisibleAttribute(True)> _
<DefaultBindingPropertyAttribute("Value")> _
<ClassInterfaceAttribute(ClassInterfaceType.AutoDispatch)> _
Public Class TrackBar _
	Inherits Control _
	Implements ISupportInitialize

Visual Basic (Uso)

Dim instance As TrackBar

[ComVisibleAttribute(true)]
[DefaultBindingPropertyAttribute("Value")]
[ClassInterfaceAttribute(ClassInterfaceType.AutoDispatch)]
public class TrackBar : Control, ISupportInitialize

Visual C++

[ComVisibleAttribute(true)]
[DefaultBindingPropertyAttribute(L"Value")]
[ClassInterfaceAttribute(ClassInterfaceType::AutoDispatch)]
public ref class TrackBar : public Control, 
	ISupportInitialize

/** @attribute ComVisibleAttribute(true) */
/** @attribute DefaultBindingPropertyAttribute("Value") */
/** @attribute ClassInterfaceAttribute(ClassInterfaceType.AutoDispatch) */
public class TrackBar extends Control implements ISupportInitialize

JScript

public class TrackBar extends Control implements ISupportInitialize

Comentarios

TrackBar es un control desplazable similar al control ScrollBar. Para configurar los intervalos entre los que se desplaza el valor de la propiedad Value de una barra de seguimiento, establezca la propiedad Minimum para especificar el extremo inferior del intervalo y la propiedad Maximum para especificar el extremo superior del intervalo.

La propiedad LargeChange define el incremento que se debe sumar o restar de la propiedad Value al hacer clic en uno de los lados del cuadro de desplazamiento. La barra de seguimiento se puede mostrar horizontal o verticalmente.

Este control se puede utilizar para entrar los datos numéricos obtenidos mediante la propiedad Value. Estos datos numéricos se pueden mostrar en un control o se pueden utilizar en el código.

Ejemplos

En el siguiente ejemplo de código se muestra un formulario que contiene un control TrackBar y un control TextBox. En el siguiente ejemplo se muestra la forma de establecer las propiedades Maximum, TickFrequency, LargeChange y SmallChange y la forma de administrar el evento Scroll. El contenido de TextBox se actualiza con el valor de la propiedad Value cuando se produce el evento Scroll.

Visual Basic

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

Public Class Form1
    Inherits System.Windows.Forms.Form

    Private WithEvents trackBar1 As System.Windows.Forms.TrackBar
    Private textBox1 As System.Windows.Forms.TextBox

    <System.STAThread()> _
    Public Shared Sub Main()
        System.Windows.Forms.Application.Run(New Form1)
    End Sub 'Main

    Public Sub New()
        Me.textBox1 = New System.Windows.Forms.TextBox
        Me.trackBar1 = New System.Windows.Forms.TrackBar

        ' TextBox for TrackBar.Value update.
        Me.textBox1.Location = New System.Drawing.Point(240, 16)
        Me.textBox1.Size = New System.Drawing.Size(48, 20)

        ' Set up how the form should be displayed and add the controls to the form.
        Me.ClientSize = New System.Drawing.Size(296, 62)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.textBox1, Me.trackBar1})
        Me.Text = "TrackBar Example"

        ' Set up the TrackBar.
        Me.trackBar1.Location = New System.Drawing.Point(8, 8)
        Me.trackBar1.Size = New System.Drawing.Size(224, 45)

        ' The Maximum property sets the value of the track bar when
        ' the slider is all the way to the right.
        trackBar1.Maximum = 30

        ' The TickFrequency property establishes how many positions
        ' are between each tick-mark.
        trackBar1.TickFrequency = 5

        ' The LargeChange property sets how many positions to move
        ' if the bar is clicked on either side of the slider.
        trackBar1.LargeChange = 3

        ' The SmallChange property sets how many positions to move
        ' if the keyboard arrows are used to move the slider.
        trackBar1.SmallChange = 2
    End Sub 'New

    Private Sub trackBar1_Scroll(ByVal sender As Object, _
                    ByVal e As System.EventArgs) Handles trackBar1.Scroll

        ' Display the trackbar value in the text box.
        textBox1.Text = trackBar1.Value
    End Sub 

End Class 'Form1

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

public class Form1 : System.Windows.Forms.Form
{
    private System.Windows.Forms.TrackBar trackBar1;
    private System.Windows.Forms.TextBox textBox1;

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

    public Form1()
    {
        this.textBox1 = new System.Windows.Forms.TextBox();
        this.trackBar1 = new System.Windows.Forms.TrackBar();

        // TextBox for TrackBar.Value update.
        this.textBox1.Location = new System.Drawing.Point(240, 16);
        this.textBox1.Size = new System.Drawing.Size(48, 20);

        // Set up how the form should be displayed and add the controls to the form.
        this.ClientSize = new System.Drawing.Size(296, 62);
        this.Controls.AddRange(new System.Windows.Forms.Control[] {this.textBox1,this.trackBar1});
        this.Text = "TrackBar Example";

        // Set up the TrackBar.
        this.trackBar1.Location = new System.Drawing.Point(8, 8);
        this.trackBar1.Size = new System.Drawing.Size(224, 45);
        this.trackBar1.Scroll += new System.EventHandler(this.trackBar1_Scroll);

        // The Maximum property sets the value of the track bar when
        // the slider is all the way to the right.
        trackBar1.Maximum = 30;

        // The TickFrequency property establishes how many positions
        // are between each tick-mark.
        trackBar1.TickFrequency = 5;

        // The LargeChange property sets how many positions to move
        // if the bar is clicked on either side of the slider.
        trackBar1.LargeChange = 3;

        // The SmallChange property sets how many positions to move
        // if the keyboard arrows are used to move the slider.
        trackBar1.SmallChange = 2;
    }


    private void trackBar1_Scroll(object sender, System.EventArgs e)
    {
        // Display the trackbar value in the text box.
        textBox1.Text = "" + trackBar1.Value;
    }
}

Visual C++

using namespace System;
using namespace System::Drawing;
using namespace System::Windows::Forms;
public ref class Form1: public System::Windows::Forms::Form
{
private:
   System::Windows::Forms::TrackBar^ trackBar1;
   System::Windows::Forms::TextBox^ textBox1;

public:
   Form1()
   {
      this->textBox1 = gcnew System::Windows::Forms::TextBox;
      this->trackBar1 = gcnew System::Windows::Forms::TrackBar;

      // TextBox for TrackBar::Value update.
      this->textBox1->Location = System::Drawing::Point( 240, 16 );
      this->textBox1->Size = System::Drawing::Size( 48, 20 );

      // Set up how the form should be displayed and add the controls to the form.
      this->ClientSize = System::Drawing::Size( 296, 62 );
      array<System::Windows::Forms::Control^>^formControls = {this->textBox1,this->trackBar1};
      this->Controls->AddRange( formControls );
      this->Text = "TrackBar Example";

      // Set up the TrackBar.
      this->trackBar1->Location = System::Drawing::Point( 8, 8 );
      this->trackBar1->Size = System::Drawing::Size( 224, 45 );
      this->trackBar1->Scroll += gcnew System::EventHandler( this, &Form1::trackBar1_Scroll );

      // The Maximum property sets the value of the track bar when
      // the slider is all the way to the right.
      trackBar1->Maximum = 30;

      // The TickFrequency property establishes how many positions
      // are between each tick-mark.
      trackBar1->TickFrequency = 5;

      // The LargeChange property sets how many positions to move
      // if the bar is clicked on either side of the slider.
      trackBar1->LargeChange = 3;

      // The SmallChange property sets how many positions to move
      // if the keyboard arrows are used to move the slider.
      trackBar1->SmallChange = 2;
   }


private:
   void trackBar1_Scroll( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {

      // Display the trackbar value in the text box.
      textBox1->Text = String::Concat( "", trackBar1->Value );
   }

};


[STAThread]
int main()
{
   Application::Run( gcnew Form1 );
}

import System.*;
import System.Drawing.*;
import System.Windows.Forms.*;

public class Form1 extends System.Windows.Forms.Form
{
    private System.Windows.Forms.TrackBar trackBar1;
    private System.Windows.Forms.TextBox textBox1;

    /** @attribute STAThread()
     */
    public static void main(String[] args)
    {
        Application.Run(new Form1());
    } //main

    public Form1()
    {
        this.textBox1 = new System.Windows.Forms.TextBox();
        this.trackBar1 = new System.Windows.Forms.TrackBar();
        // TextBox for TrackBar.Value update.
        this.textBox1.set_Location(new System.Drawing.Point(240, 16));
        this.textBox1.set_Size(new System.Drawing.Size(48, 20));
        // Set up how the form should be displayed and add the controls to the
        // form.
        this.set_ClientSize(new System.Drawing.Size(296, 62));
        this.get_Controls().AddRange(new System.Windows.Forms.Control[] { 
            this.textBox1, this.trackBar1 });
        this.set_Text("TrackBar Example");
        // Set up the TrackBar.
        this.trackBar1.set_Location(new System.Drawing.Point(8, 8));
        this.trackBar1.set_Size(new System.Drawing.Size(224, 45));
        this.trackBar1.add_Scroll(new System.EventHandler(this.trackBar1_Scroll));
        // The Maximum property sets the value of the track bar when
        // the slider is all the way to the right.
        trackBar1.set_Maximum(30);
        // The TickFrequency property establishes how many positions
        // are between each tick-mark.
        trackBar1.set_TickFrequency(5);
        // The LargeChange property sets how many positions to move
        // if the bar is clicked on either side of the slider.
        trackBar1.set_LargeChange(3);
        // The SmallChange property sets how many positions to move
        // if the keyboard arrows are used to move the slider.
        trackBar1.set_SmallChange(2);
    } //Form1

    private void trackBar1_Scroll(Object sender, System.EventArgs e)
    {
        // Display the trackbar value in the text box.
        textBox1.set_Text("" + trackBar1.get_Value());
    } //trackBar1_Scroll
} //Form1

Jerarquía de herencia

System.Object
  System.MarshalByRefObject
    System.ComponentModel.Component
      System.Windows.Forms.Control
        System.Windows.Forms.TrackBar

Seguridad para subprocesos

Todos los miembros static (Shared en Visual Basic) públicos de este tipo son seguros para la ejecución de subprocesos. No se garantiza que los miembros de instancias sean seguros para la ejecución de subprocesos.

Plataformas

Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile para Pocket PC

.NET Framework y .NET Compact Framework no admiten todas las versiones de cada plataforma. Para obtener una lista de las versiones compatibles, vea Requisitos de sistema de .NET Framework.

Información de versión

.NET Framework

Compatible con: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Compatible con: 3.5, 2.0, 1.0

Vea también

Referencia

TrackBar (Miembros)

System.Windows.Forms (Espacio de nombres)