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wpftextboxgridattached-propertieslostfocus

WPF TextBox lostfocus as attached property


I have a Grid with many TextBoxes and I want to call NotifyPropertyChanged() method to update some other controls everytime one of these TextBox-es changed the value = lost the focus (I don't want to use PropertyChanged as UpdateSourceTrigger)

This is what I can do:

<Grid TextBoxBase.TextChanged="My_TextChanged"  >
...
</Grid>

I need something like:

TextBoxBase.OnLostFocus

Solution

  • Use the lost focus event

    TextBox.LostFocus="OnTextBoxLostFocus"
    

    Filter on textboxes ;)

    private void OnTextBoxLostFocus(object sender, RoutedEventArgs e)
    {
        if(!(e.OriginalSource is TextBox))
            return;
    
        //Do stuff
    }
    

    If your properties are not changed, your Textboxes will not be updated however. You should consider mutating the data those other TextBoxes are bound to, instead of using LostFocus to update your model.

    Good luck!