I couldn't figure out how to clean up ListView items after changing the item-source or leaving a page.
Let's take your TemplateCell Example from
https://docs.telerik.com/devtools/maui/controls/listview/cells/template-cell
If i use a custom view instead of the grid it doesn't get a unloaded event or disposed or something else.
This prevents me to do a native view cleanup in my custom view. Consequently i can't disconnect Handlers resulting in memory leaks.
Am I missing something here? Something in the documentation?
Is there an example?
1 Answer, 1 is accepted
Hi Nico,
If you want to remove the ListView items, you can set the source to null/clear the Items collection. And then set the items again on the OnAppearing method.
I am not sure why you use the Unloaded event of the ContentView.
Another approach is to create a custom cell that inherits from Telerik.Maui.Controls.Compatibility.DataControls.ListView.ListViewTemplateCell and override the OnBindingContextChanged. I have attached this approach in the sample app.
Please check the code and the provided solutions and let me know if you have any additional questions. I have also left comments in the code for convenience.
Rank 1
Hi Didi,
i came back to this because our QS reported leaks.
I tried the inherited ListViewTemplateCell approach, but unfortunately onBindingContextChanged and onParentSet/onHandlerChanged etc isn't called on Android. And i can't find a way to get the parent ListView from the cell too (works on Windows).
The view in the cell is complex and i need to manually deep clean it up the entire visual tree down to avoid memory leaks.
So i need to know when and how to determine, when the cell is ready to be disposed (not recycled/unloaded for a later reuse)
Perfect would be a custom Cell inherited from ListViewTemplateCell which implements IDisposeable...
Hi Nico,
You can create a custom cell that inherits from the ListViewTemplateCell. This is displayed in the project I attached previously. If you need further implementation for this cell, I can suggest you contact the professional services team.
I've created a minimal repo example showing whats not working:
Using the unloaded event in the custom view itself to cleanup (ListViewContent in the repo):
https://github.com/baaaaif/TelerikListViewCleanup
Doing so, when navigating to the second page and back - the list view items are broken