Change windows phone toolkit pushpin content - windows-phone-8

Question

How to change the content of toolkit pushpin via program dynamically?
I've put several pushpins on the maps on the initializing, and I want to change the content of the pushpin while user put a tap on it.
This is my xaml code:
<toolkit:MapExtensions.Children>
<toolkit:MapItemsControl x:Name="MapItems">
<toolkit:MapItemsControl.ItemTemplate>
<DataTemplate>
<toolkit:Pushpin GeoCoordinate="{Binding Coordinate}" Tap="PinOnTap">
<toolkit:Pushpin.Template>
<ControlTemplate TargetType="toolkit:Pushpin">
<StackPanel>
<ContentPresenter x:Name="content" HorizontalAlignment="Center" Content="{TemplateBinding Content}" />
<Path Data="M0,0 L0,1 L1,0" Fill="{TemplateBinding Background}" Stretch="Fill" Margin="32,0" Height="12" Width="18"
Visibility="{Binding Content.Visibility, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}"
HorizontalAlignment="Left" />
<Image Source="{Binding Icon_img}" Stretch="None" HorizontalAlignment="Left"/>
</StackPanel>
</ControlTemplate>
</toolkit:Pushpin.Template>
<Border Background="White" Visibility="Collapsed" Width="200" HorizontalAlignment="Center" >
<StackPanel Orientation="Horizontal" Tap="gotoProfileFromPin">
<Image Margin="8" Source="{Binding Image}" VerticalAlignment="Top" Width="50" Height="50" />
<StackPanel>
<TextBlock Text="{Binding Uid}" Visibility="Collapsed"/>
</StackPanel>
</StackPanel>
</Border>
</toolkit:Pushpin>
</DataTemplate>
</toolkit:MapItemsControl.ItemTemplate>
</toolkit:MapItemsControl>
</toolkit:MapExtensions.Children>
And my program.cs:
private void PinOnTap(object sender, System.Windows.Input.GestureEventArgs e)
{
var popOut = ((sender as Pushpin).Content) as Border;
popOut.Visibility = System.Windows.Visibility.Visible;
var popOutImg = (popOutNew.Child as StackPanel).DataContext;
var popUser = popOutImg as UserPin;
// function to get the images by Uid
popUser.Image = new Uri(images fetch from function, UriKind.RelativeOrAbsolute);
popOutNew.Child.UpdateLayout();
e.Handled = true;
}
In PinOnTap function, I'll fetch a picture from another function and show it on the maps as toolkit:Pushpin.Content, However it can't work.
This code:
popUser.Image = new Uri(images fetch from function, UriKind.RelativeOrAbsolute);
it only change the Image source but not update the UI.
I print it's value and it source has been changed, but I donno why it didn't appear on the map (the map only show the "Border" with white background and didn't have any image inside it)

Answer 1

I think You will have to Implement INotifyPropertyChange as th change is not reflected on Xaml .