SfComboBox value is set to Null when Nested in ListView and the ListView's SelectedItem changes

[Rick Cruz]

I have a SfListView that use a SelectedItem data template to display a SfComboBox/SfPicker so the user can edit the selected item. I am finding that if the user selects a different item in the ListView, the SfComboBox's SelectionChanged is automatically called and indicates the AddedItem is null, AND the since the control is binded to the data object, the data object's value is also set to null. Then, I can see a second call to the SfComboBox's SelectionChanged to set the SelectedItem corresponding to the new selected SfListView item. 

If the user selects the original item, the default SelectedItem of the SfComboBox is set to null. 

I also confirmed that the SfComboBox's SelectionChanging event never fires when changing the selected listview item. So there is no way to cancel the data change?

I see the same behavior for the SfPicker, but an Entry control, which works as expected.

Is this a known limitation? Can I not use a ListView in this way? 

[Vallarasu Ravichandran]

Hi Rick Cruz,

Thank you for reaching out and for providing detailed observations regarding the behavior of SfComboBox or SfPicker within the SelectedItemTemplate of SfListView.

 

When you use a SfComboBox or SfPicker inside a SfListView's SelectedItemTemplate, the control is recreated every time the SelectedItem changes. This is because MAUI re-renders the template for the newly selected item. 

Since the ComboBox is bound to your model, this null value is written back to your data, unintentionally clearing it. We suspect that your data was not bound to combo box. Please ensure that the data source properly binded to combo box

 

We have prepared sample and validated from our end and we did not observe the issue in that context. We also shared a sample for your reference .

 

If possible, could you please share a minimal reproducible sample or demo project where the issue occurs? This will help us investigate further and provide a more tailored solution.

Regards,
Vallarasu R.

Attachment: ComboBoxSample_7951852.zip

[Rick Cruz]

Thanks for the reply and thorough example. Yes, I believe it was a Binding issue after all regarding the data updates. 

[Preethi Rajakandham]

Hi Rick Cruz,

You are welcome.

Please let us know if you require any further assistance on this. We will be happy to assist you.

Regards,

Preethi R