2018-11-15-UWP-how-to-get-the-touch-width

The touch width can help us to make a gorgeous application. This article tells you how to get the touch width from the PointEvent in UWP.

Opening the VisualStudio and create an empty UWP application.

We should open the MainPage.xaml and add the background in the Grid to make the Grid can get the PointMove event.

<Grid Background="Transparent">

    </Grid>

Then we can open the MainPage.xaml.cs to write the code to get the PointerMove event.

public MainPage()
        {
            InitializeComponent();

            Content.PointerMoved += MainPage_PointerMoved;
        }

        private void MainPage_PointerMoved(object sender, PointerRoutedEventArgs e)
        {

        }

We can use GetCurrentPoint to get the PointerPoint.

private void MainPage_PointerMoved(object sender, PointerRoutedEventArgs e)
        {
            var point = e.GetCurrentPoint(this);
        }

And we can find the ContactRect in Properties. We can get the touch width from ContactRect.

private void MainPage_PointerMoved(object sender, PointerRoutedEventArgs e)
        {
            var point = e.GetCurrentPoint(this);
            Rect rect = point.Properties.ContactRect;
        }

To get the touch width.

private void MainPage_PointerMoved(object sender, PointerRoutedEventArgs e)
        {
            var point = e.GetCurrentPoint(this);
            Rect rect = point.Properties.ContactRect;
            Debug.WriteLine($"Touch rect width={rect.Width},height={rect.Height}");
        }

We also can use ContactRectRaw in Properties.

private void MainPage_PointerMoved(object sender, PointerRoutedEventArgs e)
        {
            var point = e.GetCurrentPoint(this);
            Rect rect = point.Properties.ContactRect;
            Debug.WriteLine($"Touch rect width={rect.Width},height={rect.Height}");
            rect = point.Properties.ContactRectRaw;
            Debug.WriteLine($"Touch raw rect width={rect.Width},height={rect.Height}");
        }

Try to run the code and touch the application and you can watch the output windows that prints the touch width.