Have to click away twice from Calendar in WPF

Question

Edit 2: Thank you all for your feedback. I solved the problem by adding this to my SelectedDatesChanged event:

Mouse.Capture(null);

When I select a

Answer 1

So it seems the Calendar captures the Mouse exclusively, One option could be to make a AttachedProperty to release the capture when the user clicks

Example:

public static class CalandarHelper 
{
    public static readonly DependencyProperty SingleClickDefocusProperty =
        DependencyProperty.RegisterAttached("SingleClickDefocus", typeof(bool), typeof(Calendar)
        , new FrameworkPropertyMetadata(false, new PropertyChangedCallback(SingleClickDefocusChanged)));

    public static bool GetSingleClickDefocus(DependencyObject obj) {
        return (bool)obj.GetValue(SingleClickDefocusProperty);
    }

    public static void SetSingleClickDefocus(DependencyObject obj, bool value) {
        obj.SetValue(SingleClickDefocusProperty, value);
    }

    private static void SingleClickDefocusChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        if (d is Calendar) 
        {
            Calendar calendar = d as Calendar;
            calendar.PreviewMouseDown += (a, b) =>
            {
                if (Mouse.Captured is Calendar || Mouse.Captured is System.Windows.Controls.Primitives.CalendarItem)
                {
                    Mouse.Capture(null);
                }
            };
        }
    }
}

Now you can apply this AttachedProperty to your Calender and it will defocus once an item is selected.

Full Example:

Xaml:

Code:

using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;

namespace WpfApplication2 
{
    /// 

    /// Interaction logic for MainWindow.xaml
    /// 
    public partial class MainWindow : Window 
    {
        public MainWindow() 
        {
            InitializeComponent();
        }
    }

    public static class CalandarHelper 
    {
        public static readonly DependencyProperty SingleClickDefocusProperty =
            DependencyProperty.RegisterAttached("SingleClickDefocus", typeof(bool), typeof(Calendar)
            , new FrameworkPropertyMetadata(false, new PropertyChangedCallback(SingleClickDefocusChanged)));

        public static bool GetSingleClickDefocus(DependencyObject obj) {
            return (bool)obj.GetValue(SingleClickDefocusProperty);
        }

        public static void SetSingleClickDefocus(DependencyObject obj, bool value) {
            obj.SetValue(SingleClickDefocusProperty, value);
        }

        private static void SingleClickDefocusChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            if (d is Calendar) 
            {
                Calendar calendar = d as Calendar;
                calendar.PreviewMouseDown += (a, b) =>
                {
                    if (Mouse.Captured is Calendar || Mouse.Captured is System.Windows.Controls.Primitives.CalendarItem)
                    {
                        Mouse.Capture(null);
                    }
                };
            }
        }
    }
}