Geek
Cool Guy

Instead of using += to set event handlers you should use the DependencyPropertyDescriptor method that Brian used for the Visibility issue. Internally the WPF Dependency system uses weak refrences for event handlers thus the memory leak issue is avoided. I will post example code showing my solution derived from yours. Thanks for the good work!

I found an issue when I was trying to show an animated image in the Adorner. The image would only change when the adorner was hidden and reloaded. The solution I found was here:
http://stackoverflow.com/questions/583808/animation-inside-an-adorner-calling-onrender

Adding:
base.AddVisualChild(contentPresenter);
as the last call in the CueBannerAdorner constructor fixed this.

My problem is similiar to the TextBox problem not showing CueBanner when external events update the bound value…

I cannot get the ComboBox to work. I have two (2) ComboBoxes for a Master-Detail UI. When the SelectedItem in MasterComboBox1 changes, I need DetailComboBox2 to show the CueBanner. I am setting the selectedItem to null, and the TextBox of the ComboBox clears – yet no CueBanner. There seems to be a disconnect between the Dependency Properties ComboBox.TextProperty and ComboBox.SelectedxxxProperty. I either get the value and the CueBanner superimposed or nothing at all.

Any help resolving this would be much appreciated. Thank You.

Mybextbox.CueBanner = “This is my CueText”;

It seems that the above code does compile, however it breaks the Design view in VS2008. The TextBox that I’ve put the CueBannerService in is now highlighted with an error of “Object reference not set to an instance of an object.”

If I remove the line with setting the event of TextChanged the design view works fine.

Any thoughts?

private static void CueBannerPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
Control control = (Control)d;
TextBox tb = (TextBox)d;
tb.Loaded += control_Loaded;
control.Loaded += control_Loaded;
if (d is TextBox)
{
tb.GotFocus += control_GotFocus;
tb.LostFocus += control_Loaded;
tb.TextChanged += textbox_Changed;
}

then in my textbox_Changed

private static void textbox_Changed(object sender, RoutedEventArgs e)
{
TextBox c = (TextBox)sender;
if (c.Text != “”)
{
RemoveCueBanner(c);
}
}

If you look at the GotFocus event handler, you can see that we call the RemoveCueBanner() method if there is text in the textbox.

I have a question though, how would we have the adorner disappear once the Text property in the TextBox changes?