WPF Drawing Application

December 04, 2015

The following is a XAML page that allows the user to draw on it. This was written and tested under a Windows 10 desktop application, but should work for WPF. Here’s the XAML:

[code lang=“XML”]




The background is a different colour to identify the canvas.

There's the code to allow drawing:



``` csharp

        
        Path \_currentPath;

        private void Canvas\_PointerPressed(object sender, Windows.UI.Xaml.Input.PointerRoutedEventArgs e)
        {            
            \_currentPath = new Path
            {
                Data = new PathGeometry
                {
                    Figures = { new PathFigure
                    {
                        StartPoint = e.GetCurrentPoint((UIElement)sender).Position,
                        Segments = { new PolyLineSegment() }
                    }}
                },
                Stroke = new SolidColorBrush(Colors.Black),
                StrokeThickness = 5
            };

            Canvas.Children.Add(\_currentPath);
        }

        private void Canvas\_PointerMoved(object sender, PointerRoutedEventArgs e)
        {
            if (\_currentPath == null) return;

            var pls = (PolyLineSegment)((PathGeometry)\_currentPath.Data).Figures.Last().Segments.Last();
            pls.Points.Add(e.GetCurrentPoint((UIElement)sender).Position);
            
        }

        private void Canvas\_PointerReleased(object sender, PointerRoutedEventArgs e)
        {
            \_currentPath = null;
        }

As you can see, it doesn’t do anything for my drawing ability:

drawing

It’s all the code behind and, while I typically shy away from this, it seems to fit well for an application such as this (as the drawing relates more to the view than to anything else).



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