wpf - Is there a way to cancel TabControl.Items.CurrentChanging? -

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there unfortunately no tabcontrol.selectionchanging event (selector.selectionchanging), struggling implement behavior can cancel changing request.

i tried handle tabcontrol.items.currentchanging (the items property , itemcollection) event setting e.cancel (of currentchangingeventargs) true, ui is updated new tab although item not changed in collection.

is there way prevent user switching different tabitem when condition dissatisfied?

i don't know exact reason why happens, , annoys me greatly.

but here's workaround it:

in sample below, checkbox "locking" current tab. checked means user can't change tab. 

void items_currentchanging(object sender, currentchangingeventargs e) {     if (checkbox1.ischecked.value)     {         var item = ((icollectionview)sender).currentitem;          e.cancel = true;          tabcontrol1.selecteditem = item;     } }

basically, happens (if understand correctly) visual tree gets updated, logical tree not. above way forces visual sync logical tree.


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