Show a Continuous Animation During an Asynchronous Process : Thread « Windows Presentation Foundation « VB.Net Tutorial






<Window x:Class="WpfApplication1.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="WPF" Height="220" Width="180">
    <Window.Resources>
        <Storyboard  x:Key="PulseStoryboard" AutoReverse="True" >
            <ColorAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="ellipse" Storyboard.TargetProperty="(Shape.Fill).(GradientBrush.GradientStops)[0].(GradientStop.Color)">
                <SplineColorKeyFrame KeyTime="00:00:00.5000000" Value="Lime"/>
            </ColorAnimationUsingKeyFrames>
            <ColorAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="ellipse" Storyboard.TargetProperty="(Shape.Fill).(GradientBrush.GradientStops)[1].(GradientStop.Color)">
                <SplineColorKeyFrame KeyTime="00:00:00.5000000" Value="Green"/>
            </ColorAnimationUsingKeyFrames>
        </Storyboard>
    </Window.Resources>

    <Grid x:Name="LayoutRoot" >
        
        <Grid.RowDefinitions>
            <RowDefinition Height="*"/>
            <RowDefinition Height="60" />
        </Grid.RowDefinitions>
      
        <Ellipse Width="100" Height="100" Margin="10" Stroke="{x:Null}" x:Name="ellipse">
            <Ellipse.Fill>
                <RadialGradientBrush GradientOrigin="0.25,0.25">
                    <GradientStop Offset="0" Color="Red"/>
                    <GradientStop Offset="1" Color="Blue"/>
                </RadialGradientBrush>
            </Ellipse.Fill>
        </Ellipse>
       
        <Button Margin="10" Content="Start" Grid.Row="1" x:Name="button" Click="button_Click"/>
    </Grid>
</Window>
//File:Window.xaml.vb

Imports System.Windows

Imports System.Threading
Imports System.ComponentModel
Imports System.Windows.Media.Animation

Namespace WpfApplication1
  Public Partial Class Window1
    Inherits Window
    Private pulseStoryboard As Storyboard
    Private worker As BackgroundWorker

    Public Sub New()
      InitializeComponent()

      pulseStoryboard = DirectCast(Me.Resources("PulseStoryboard"), Storyboard)
      pulseStoryboard.RepeatBehavior = RepeatBehavior.Forever
      worker = New BackgroundWorker()

      AddHandler worker.DoWork, New DoWorkEventHandler(AddressOf worker_DoWork)
      AddHandler worker.RunWorkerCompleted, New RunWorkerCompletedEventHandler(AddressOf worker_RunWorkerCompleted)
    End Sub

    Private Sub button_Click(sender As Object, e As RoutedEventArgs)
      pulseStoryboard.Begin(Me, True)
      worker.RunWorkerAsync()
      button.IsEnabled = False
    End Sub

    Private Sub worker_RunWorkerCompleted(sender As Object, e As RunWorkerCompletedEventArgs)
      button.IsEnabled = True
      pulseStoryboard.[Stop](Me)
    End Sub

    Private Sub worker_DoWork(sender As Object, e As DoWorkEventArgs)
      For i As Integer = 1 To 50
        Thread.Sleep(100)
      Next
    End Sub
  End Class
End Namespace
WPF Show A Continuous Animation During An Asynchronous Process








16.115.Thread
16.115.1.Create a multi threaded web browsing application.Create a multi threaded web browsing application.
16.115.2.Show a Continuous Animation During an Asynchronous ProcessShow a Continuous Animation During an Asynchronous Process
16.115.3.Load the Data for a Window Asynchronously After It Has RenderedLoad the Data for a Window Asynchronously After It Has Rendered
16.115.4.Check Whether You Are Running on the UI ThreadCheck Whether You Are Running on the UI Thread
16.115.5.Ensure That You Are Running on the UI ThreadEnsure That You Are Running on the UI Thread
16.115.6.A Cancellable ProgressBar While Processing on a Background ThreadA Cancellable ProgressBar While Processing on a Background Thread
16.115.7.Show a Continuous Progress Bar While Processing on a Background ThreadShow a Continuous Progress Bar While Processing on a Background Thread
16.115.8.Execute a Method Asynchronously Using the Dispatcher QueueExecute a Method Asynchronously Using the Dispatcher Queue
16.115.9.Thread Sleep in Button Click handlerThread Sleep in Button Click handler
16.115.10.Execute a Method Asynchronously Using a Background Worker ThreadExecute a Method Asynchronously Using a Background Worker Thread
16.115.11.Track the Progress of a Background Worker ThreadTrack the Progress of a Background Worker Thread
16.115.12.Support the Cancellation of a Background Worker ThreadSupport the Cancellation of a Background Worker Thread
16.115.13.Create a Background Worker Thread in XAMLCreate a Background Worker Thread in XAML
16.115.14.WPF ThreadingWPF Threading
16.115.15.BlockThread.xamlBlockThread.xaml
16.115.16.Keep the UI from becoming non-responsive in single threaded application which performs a long operation.Keep the UI from becoming non-responsive in single threaded application which performs a long operation.