在DependencyProperty的setter上的C＃触发器方法

Question

I am trying to trigger a method every time the property Minutes is changed, however it never happens. I am not setting the property through XAML , it is being set by a bidding.

public static DependencyProperty MinutesProperty =
    DependencyProperty.Register("Minutes", typeof(string), typeof(TimelineControl));

public string Minutes
{
    get { return (string)GetValue(MinutesProperty); }
    set { 
        SetValue(MinutesProperty, value);
        my_method();
    }
}

public void my_method()
{
    Console.WriteLine("foo bar");
}

What am I doing wrong?

Answer 1

If you are setting the property through XAML, then your setter won't be called. To properly handle property changes, you should add a callback to the property's metadata when registering:

public static DependencyProperty MinutesProperty =
    DependencyProperty.Register("Minutes", typeof(string), typeof(TimelineControl),
    new PropertyMetadata(OnMinutesChanged));

private static void OnMinutesChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
    // Handle change here

    // For example, to call the my_method() method on the object:
    TimelineControl tc = (TimelineControl)d;
    tc.my_method();
}