Question

I’m working on a project where I have to add a small preview pane and a about box whenever a user is hovering the buttons on the main window.

For the examlpe: I have a window – preview.xaml, and my main window called MainWindow.xaml.

How do I set the preview windows bottom to appear on the top of button1 on the MainWindow?

I tried something like this without any luck:

public preview()
{
   InitializeComponent();
   this.WindowStartupLocation = WindowStartupLocation.Manual;
   Top = mainWindow.button1.Margin.Top;
}

I hope my ramblings makes any sense…

Any help is greatly appreciated!

Answer 1

You need to set Left and Top window properties to screen coordinates, button margins won’t help here. Use PointToScreen function to obtain screen coordinates of your buttons:

    private void button1_MouseEnter(object sender, MouseEventArgs e)
    {
        var control = ((FrameworkElement)sender);
        // get screen coordinates of (0,0) point of button
        var location = control.PointToScreen(new Point(0, 0));
        var w = new preview()
        {
            WindowStartupLocation = System.Windows.WindowStartupLocation.Manual,
            ShowActivated = false,
        };
        w.Top = location.Y - w.Height;
        w.Left = location.X + (control.ActualWidth - w.Width) / 2;
        w.Show();
    }