如何仅在Popup外部单击时检测Popup LostFocus，而不是隐藏弹出窗口

Question

I have a custom UWP Control where i use Popup in it and how can i detect the Popup Lost Focus?

I have several tabs in my control and when i click any of my tab, the popup should be visible and vise versa and i have states for my tab to indicate the popup state.

Now i need to close the Popup when clicked outside the popup. I have done my research and found a property IsLightDismissEnabled which does close the Popup automatically and invokes LostFocus. But when switching between the Tabs the popup should not be closed , but when i use this property the popup is automatically closing which is not i desired.

This is the code i have In the code im updating the state based on whether Popup is already open and whether new tab is selected. And in State property im updating the Popup visibility

if (this.PART_Popup != null)
      {
           this.PART_Popup.LostFocus += this.PART_Popup_LostFocus;
           this.PART_Popup.IsLightDismissEnabled = true;
       }


private void PART_Popup_LostFocus(object sender, RoutedEventArgs e)
   {

        if (this.ParentItemsControl != null)
            {
                if (this.ParentItemsControl.State == State.Adorner)
                {
                    if (this.ParentItemsControl.PART_Popup.IsOpen && this.ParentItemsControl.SelectedItem == this)
                    {
                        this.ParentItemsControl.State = State.Hide;
                    }
                }
          else
                {
                    this.ParentItemsControl.State = State.Normal;
                }
            }
        }

Is there any way to invoke only LostFocus and i can have my code whether to close the Popup or stay it open(When Switching Tabs) ?? I also found when enabling the mentioned property, some double tap events were not working and i dont know why . So any help is appreciated .

Answer 1

When you use the property IsLightDismissEnabled , it will always close the Popup and I don't think you shouldn't use this property if you are willing to keep the functionality of your custom control. Rather you should handle the opening and closing manually.

I think instead of trying to handle the LostFocus event, You should try the Opened and Closed event instead and utilize the writable property IsOpen to manually open and close the Popup .

Hope that helps