Using a Pan Window and Interactive Modes in Silverlight

SilverlightTutorials

Take the following steps to start a project and to add some code that will demonstrate the various interactive modes of the LEADTOOLS Silverlight Control and the Pan Viewer:

Start Visual Studio .NET.
Start with the project that you created in Loading and displaying an image in Silverlight.

Open the Page.xaml file and copy the below xaml code into the editor:

[XAML]

             <UserControl x:Class="Load_And_Display.MainPage"
               xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
               xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
               xmlns:Leadtools_Windows_Controls="clr-namespace:Leadtools.Windows.Controls;assembly=Leadtools.Windows.Controls"
               Width="800" Height="600">
               <Grid x:Name="LayoutRoot" Background="White">
                 <Grid.ColumnDefinitions>       
                     <ColumnDefinition Width="5*"/>
                     <ColumnDefinition Width="2*"/>
                 </Grid.ColumnDefinitions>
                 
                 <ScrollViewer VerticalScrollBarVisibility="Disabled" HorizontalScrollBarVisibility="Disabled" Grid.Column="0">
                     <StackPanel Orientation="Vertical" >
                         <Button Name="myButton" Content="Load" FontSize="30" Click="Button_Click" Height="40"></Button>
                         <Leadtools_Windows_Controls:RasterImageViewer x:Name="viewerControl" SizeMode="Normal" Height="550"></Leadtools_Windows_Controls:RasterImageViewer> 
                     </StackPanel>
                 </ScrollViewer>
                 
                 <ScrollViewer VerticalScrollBarVisibility="Disabled" HorizontalScrollBarVisibility="Disabled" Grid.Column="1">
                     <StackPanel Orientation="Vertical" >
                         <TextBlock Text="Pan Window :"/>
                         <Leadtools_Windows_Controls:ImagePanViewer x:Name="_imagePanViewer" Width="150" Height="150" HorizontalAlignment="Left"></Leadtools_Windows_Controls:ImagePanViewer>
                         <TextBlock Text="Interactive Mode :"/>
                         <ComboBox Name="_cmbInteractiveMode" SelectedIndex="0" Width="200" HorizontalAlignment="Left" SelectionChanged="ComboBox_SelectionChanged">
                             <ComboBoxItem Content="None"/>
                             <ComboBoxItem Content="Pan"/>
                             <ComboBoxItem Content="Center At"/>
                             <ComboBoxItem Content="Zoom To"/>
                             <ComboBoxItem Content="Scale"/>
                             <ComboBoxItem Content="Magnify Glass"/>
                         </ComboBox>
                     </StackPanel>
                 </ScrollViewer>    
               </Grid>
             </UserControl>

Switch to Page.xaml code view (right-click Page.xaml in the solution explorer then select View Code) and add the following class function:

[Visual Basic]

             Private Sub ComboBox_SelectionChanged(ByVal sender As Object, ByVal e As SelectionChangedEventArgs)
               If _cmbInteractiveMode Is Nothing OrElse _cmbInteractiveMode.SelectedItem Is Nothing Then
                  Return
               End If
            
               Dim item As String = (CType(IIf(TypeOf _cmbInteractiveMode.SelectedItem Is ComboBoxItem, _cmbInteractiveMode.SelectedItem, Nothing), ComboBoxItem)).Content.ToString()
            
               Select Case item
                  Case "Pan"
                     viewerControl.InteractiveMode = Leadtools.Windows.Controls.InteractiveMode.Pan
            
                  Case "Center At"
                     viewerControl.InteractiveMode = Leadtools.Windows.Controls.InteractiveMode.CenterAt
            
                  Case "Magnify Glass"
                     viewerControl.InteractiveMode = Leadtools.Windows.Controls.InteractiveMode.MagnifyGlass
            
                  Case "Scale"
                     viewerControl.InteractiveMode = Leadtools.Windows.Controls.InteractiveMode.Scale
            
                  Case "Zoom To"
                     viewerControl.InteractiveMode = Leadtools.Windows.Controls.InteractiveMode.ZoomTo
            
                  Case Else
                     viewerControl.InteractiveMode = Leadtools.Windows.Controls.InteractiveMode.None
               End Select
             End Sub

[C#]

             private void ComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
             {
               if (_cmbInteractiveMode == null || _cmbInteractiveMode.SelectedItem == null)
                  return;
            
               string item = (_cmbInteractiveMode.SelectedItem as ComboBoxItem).Content.ToString();
            
               switch (item)
               {
                  case "Pan":
                     viewerControl.InteractiveMode = Leadtools.Windows.Controls.InteractiveMode.Pan;
                     break;
            
                  case "Center At":
                     viewerControl.InteractiveMode = Leadtools.Windows.Controls.InteractiveMode.CenterAt;
                     break;
            
                  case "Magnify Glass":
                     viewerControl.InteractiveMode = Leadtools.Windows.Controls.InteractiveMode.MagnifyGlass;
                     break;
            
                  case "Scale":
                     viewerControl.InteractiveMode = Leadtools.Windows.Controls.InteractiveMode.Scale;
                     break;
            
                  case "Zoom To":
                     viewerControl.InteractiveMode = Leadtools.Windows.Controls.InteractiveMode.ZoomTo;
                     break;
            
                  default:
                     viewerControl.InteractiveMode = Leadtools.Windows.Controls.InteractiveMode.None;
                     break;
               }
             }

Update the Button_Click event as shown below:

[Visual Basic]

             Private Sub Button_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
               Try  
                  Dim ofd As OpenFileDialog = New OpenFileDialog()
                  If ofd.ShowDialog() = True Then
                     Dim fileStream As FileStream = ofd.File.OpenRead()
                     Try
                        Dim codecs As RasterCodecs = New RasterCodecs()
                        viewerControl.Image = codecs.Load(fileStream)
                        _imagePanViewer.Source = viewerControl
                     Finally
                        fileStream.Dispose()
                     End Try
                  End If
               Catch ex As Exception
                  MessageBox.Show(ex.Message)
               End Try
             End Sub

[C#]

             private void Button_Click(object sender, RoutedEventArgs e)
             {
               try
               {
                  OpenFileDialog ofd = new OpenFileDialog();
                  if (ofd.ShowDialog() == true)
                  {
                     using (FileStream fileStream = ofd.File.OpenRead())
                     {
                        RasterCodecs codecs = new RasterCodecs();
                        viewerControl.Image = codecs.Load(fileStream);
                        _imagePanViewer.Source = viewerControl;
                     }
                  }
               }
               catch (Exception ex)
               {
                  MessageBox.Show(ex.Message);
               }
             }

Build, and Run the program to test it.

Click the "Load" button, and select an image.

NOTE: if you encounter and "Invalid File Format" or "Feature Not Supported" exception, please refer to the topic Invalid File Format/Feature Not Supported.