I have a listbox that I'm doing some databinding. As you can see I have some images associated with the data that I'm displaying... Everything is working great, except that when I change themes I need to change my image to the black images. I can't seem to figure out how to change the images when they 开发者_开发百科are bound like this.
Any ideas?
<ListBox x:Name="lbPharm" ItemsSource="{Binding col}">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel x:Name="DataTemplateStackPanel" Orientation="Horizontal">
<TextBlock FontFamily="Segoe WP Semibold" FontWeight="Bold" FontSize="30" VerticalAlignment="Top" Margin="20,10">*</TextBlock>
<StackPanel>
<TextBlock x:Name="ItemText" Text="{Binding name}" FontSize="{StaticResource PhoneFontSizeLarge}"/>
<TextBlock x:Name="ItemNumber" Text="{Binding number}" FontSize="{StaticResource PhoneFontSizeNormal}"/>
</StackPanel>
<Image Source="Images/phone.png" Margin="20,0" x:Name="phone" Visibility="Visible">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener Tap="GestureListener_Tap_Phone"/>
</toolkit:GestureService.GestureListener>
</Image>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
You should create a binding for the image source instead of setting it explicitly in XAML.
<ListBox x:Name="lbPharm" ItemsSource="{Binding col}">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel x:Name="DataTemplateStackPanel" Orientation="Horizontal">
<TextBlock FontFamily="Segoe WP Semibold" FontWeight="Bold" FontSize="30" VerticalAlignment="Top" Margin="20,10">*</TextBlock>
<StackPanel>
<TextBlock x:Name="ItemText" Text="{Binding name}" FontSize="{StaticResource PhoneFontSizeLarge}"/>
<TextBlock x:Name="ItemNumber" Text="{Binding number}" FontSize="{StaticResource PhoneFontSizeNormal}"/>
</StackPanel>
<!-- Image source is bound to a property -->
<Image Source="{Binding ImageSource}" Margin="20,0" x:Name="phone" Visibility="Visible">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener Tap="GestureListener_Tap_Phone"/>
</toolkit:GestureService.GestureListener>
</Image>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
Now, just update the property in your view model as needed, as long as the class containing the property implements INotifyPropertyChanged
the new image will show up in your ListBox
.
The ImageSource
property may have to be a BitmapImage
instead of a string. XAML must use a converter to convert your path string when it is used as a literal but I think it doesn't do this if you use a binding. Or you could use your own converter. Either way, construct a BitmapImage
as follows:
new BitmapImage( new Uri( "/path/to/image.png", UriKind.Relative ) )
EDIT
Adding an example:
<DataTemplate x:Key="LongListSelectorItemTemplate">
<StackPanel VerticalAlignment="Top"
Orientation="Horizontal">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener Tap="OnTap" />
</toolkit:GestureService.GestureListener>
<Image Source="{Binding ImageSource}"
MinHeight="32"
MinWidth="32"
MaxHeight="48"
MaxWidth="48" />
<StackPanel>
<TextBlock Text="{Binding Name}"
Style="{StaticResource PhoneTextExtraLargeStyle}"
Margin="12,10,12,0" />
<TextBlock Text="{Binding Parent}"
Foreground="{StaticResource PhoneAccentBrush}"
Style="{StaticResource PhoneTextSubtleStyle}"
Margin="24,0,12,10" />
</StackPanel>
</StackPanel>
</DataTemplate>
Corresponding view model:
public class Item : INotifyPropertyChanged
{
#region Private Members
private string _name = null;
private string _imageSource = null;
private string _parent = null;
#endregion
public string Name
{
get
{
return _name;
}
set
{
if( value != _name ) {
_name = value;
NotifyPropertyChanged( "Name" );
}
}
}
public string Parent
{
get
{
return _parent;
}
set
{
if( value != _parent ) {
_parent = value;
NotifyPropertyChanged( "Parent" );
}
}
}
public string ImageSource
{
get
{
return _imageSource;
}
set
{
if( value != _imageSource ) {
_imageSource = value;
NotifyPropertyChanged( "ImageSource" );
}
}
}
#region INotifyPropertyChanged Members
public event PropertyChangedEventHandler PropertyChanged;
private void NotifyPropertyChanged( String propertyName )
{
PropertyChangedEventHandler handler = PropertyChanged;
if( null != handler ) {
handler( this, new PropertyChangedEventArgs( propertyName ) );
}
}
#endregion
}
This is code from a project I'm working on, it is similar to your case except I'm displaying the image with a LongListSelector
instead of a ListBox
. And it looks like I mislead you earlier about not being able to use a string directly for the image source, I'm doing exactly that and it works. Sorry about that.
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