How do I detect a ListBox mouse click, then deselect other ListBoxes?

C# wpf - There are blue, yellow, and red cities in the ListBoxes (Pandemic Game). This is the red ListBox xaml:



A MouseDoubleClick jumps to the correct code in xaml.cs.

I've added MouseDown="gLBxOriginalRedCities_MouseDown". 



When I click a city in "gLBxOriginalRedCities" the code does not jump to

private void gLBxOriginalRedCities_MouseDown(object sender, MouseButtonEventArgs e)
{
    gLBxOriginalBlueCities.UnselectAll();
    gLBxOriginalYellowCities.UnselectAll();
}


How do I detect a ListBox mouse click, and then unselect the other ListBox items?

The MouseDown event might not be the best choice for this scenario because the ListBox control uses this event internally to fire its SelectionChanged event1. Therefore, your MouseDown event handler might not be called.

Instead, you can use the PreviewMouseLeftButtonDown event1. This event is a tunneling event, which means it starts at the root of the visual tree and works its way down to the control that generated the event1. Since your code would get the chance to handle the event prior to the ListBoxItem, this will get fired1.

Here’s how you can modify your XAML:

And your event handler in C#:

private void gLBxOriginalRedCities_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
    gLBxOriginalBlueCities.UnselectAll();
    gLBxOriginalYellowCities.UnselectAll();
}

This code will unselect all items in the other ListBox controls when you click an item in gLBxOriginalRedCities1.

Remember to replace the variables with your own values. Also, ensure that the new driver is properly included in your project1.

Thanks

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Naimish Makwana2y agoPosted Mar 26, 2024, 5:01 AM Accepted answer The MouseDown event might not be the best choice for this scenario because the ListBox control uses this event internally to fire its SelectionChanged event1. Therefore, your MouseDown event handler might not be called. Instead, you can use the PreviewMouseLeftButtonDown event1. This event is a tunneling event, which means it starts at the root of the visual tree and works its way down to the control that generated the event1. Since your code would get the chance to handle the event prior to the ListBoxItem, this will get fired1. Here’s how you can modify your XAML: And your event handler in C#: private void gLBxOriginalRedCities_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e) { gLBxOriginalBlueCities.UnselectAll(); gLBxOriginalYellowCities.UnselectAll(); } This code will unselect all items in the other ListBox controls when you click an item in gLBxOriginalRedCities1. Remember to replace the variables with your own values. Also, ensure that the new driver is properly included in your project1. Thanks