I am trying to use Command Binding to dynamically add tabs to the control. I followed the demo sample (http://demos.telerik.com/silverlight/#TabControl/Databinding
). However, the command binding for the Add and Remove buttons don't work always. The problem is with the InvalidateCanExecute call. The button state is not changing properly. Initially it works, then once the button is disabled, then the re-enable logic doesn't seem to work always. When I stepped through the code, I found that the CanExecuteChangeHandler is lost (initially the handler count is 1 and when the issue shows up, the handler count drops to 0).
I checked your online sample. Unfortunately, the sample also exhibits the same problem. It doesn't always exhibit the issue. After quite a few clicks (like Keep Adding tabs till Add is disabled in all the tabs except the first one (the first tab's Add button never gets disabled), click remove a few times, then add, etc...) the issue shows itself.
I tried to find a definite sequence of clicks that would always reproduce the issue, but couldn't. However, the issue eventually happens. Sometimes sooner, sometimes later.
Here is the sequence I used to reproduce (not consistent/definite number of steps though):
1. Click on the Add button of the first tab till the max allowed (disabling the add button from all tabs except the first)
2. Click on the disabled Add buttons of the tabs one by one starting from the last to the first
3. Click on the delete button of the second tab repeatedly, deleting all the tabs except the first
4. Repeat steps 1 to 3 a few times
5. Perform step 1
6. Perform step 2
7. Click on the Add button of the second tab a few times
8. Click on the Add button of the first tab a few times
9. Click on the Add button of the second tab a few times
10. Click the delete button of the second tab once
11. You will see that the add buttons are not re-enabled for all the tabs
I don't believe the sequence has anything to do with the issue. I belive, the CanExecuteChangeHandler gets lost eventually, causing the controls not to change state.
I am evaluating the RadControls for an upcoming project. The UI needs nested tab controls and the dynamic addition of tabs. Your demo kind of reflected what I needed.
Any help would be appreciated..