When our Ribbon implementation does not have enough space and shows the down-arrow to expand out the collapsed group clicking on the arrow freezes our application and output has the error below. Do you guys have any idea what could cause it?
We did re-style the app a lot including your Ribbon so something you are looking for or trying to use in the visualtree might be broken. Any hints on debugging through this would be appreciated.
Error:
System.Windows.Data Error: 8 : Cannot save value from target back to source. BindingExpression:Path=IsOpen; DataItem='RibbonGroup' (Name=''); target element is 'DropDownToggle' (Name='PART_RibbonGroupButton'); target property is 'IsDroppedDown' (type 'Boolean') InvalidOperationException:'System.InvalidOperationException: Logical tree depth exceeded while traversing the tree. This could indicate a cycle in the tree.
I don't really have any ideas about debugging this but if you can provide a sample that demonstrates the issue we can see if we can find what is leading to that exception. It would seem that it is something about your custom RibbonGroup template since that is where that part exists.
Andrew,
You were correct, the template was broken. When we originally modified it one part was deleted by accident that should have been left alone.
What i did was use WinDiff to compare the original and modified template until i found the issue. Restoring the deleted part of XAML caused the bug to go away.
Appreciate your help