At that time the ListBoxItems have been set up and the Items. Count returns the correct number of ListBoxItems. Thanks, Kalle. Wednesday, October 25, AM. Actually in the Loaded event, you cannot ensure that the ItemContainerGenerator is done with generating the ListBoxItems for the ListBox, to get the code working, you can do something in the loaded event handleras follows: myListBox.
Well the solution is much simpler than anyone has ever thought. Just set the IsExpanded property of the newly inserted node to true and that would take away all the pain : -Kuntal Kishore.
Tuesday, October 26, PM. I am using WPF, I have 2 projects: - forms projects - client project used to load the available forms in the forms project In the forms project, I have a ListBox and I bound it to a DataTemplate containing the UI of vendors information.
Let's say at runtime, the listbox is filled with 2 vendors I need to access the element with its value from the client project. Items[i] ; I get an error since lbi is always null and the error says it can't return null!!! How can I solve this? Thursday, November 25, PM. Wednesday, June 8, AM. Thank you! It will be very useful to mark any objects which have ItemContainerGenerator.
I applied my ListView and worked well :. Thursday, February 16, AM. Step through the code with the debugger and see if there is actually nothing retured or if the as -cast is just wrong and thus turns it to null you could just use a normal cast to get a proper exception.
One problem that frequently occurs is that when an ItemsControl is virtualizing for most of the items no container will exist at any point in time. Also i would not recommend dealing with the item containers directly but rather binding properties and subscribing to events via the ItemsControl.
After trying many solutions suggesting to add IsExpanded and IsSelected to underlying object and binding to them in TreeViewItem style, while this mostly works in some case it still fails There are a few other minor differences between the ListBox and ListView controls What is The difference between ListBox and ListView - which should not essentially affect your use case. See the below implementation. Which helps me to avoid the same issue.
Set your application VirtualizingStackPanel. See the link for detailed info. For anyone still having issues with this, I was able to work around this issue by ignoring the first selection changed event and using a thread to basically repeat the call. Here's what I ended up doing:. There are some answers for WPF like applying Dispatcher. On the other hand if I scroll through list and then press AppBar icon it just works fine.
But users can directly press on icon right after data bound and they will not see some of the checkboxes. You're passing it an index, when it needs an object that is directly related to the ItemsSource. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams?
Collectives on Stack Overflow. Learn more. Asked 7 years, 2 months ago. Active 7 years, 2 months ago. Viewed times. Is there any workaround for this issue for Windows Phone 8? ContainerFromIndex i ; if item! Improve this question.
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