How to set the stroke opacity for InkCanvas pen color?

Question

How to set the opacity for ink stroke in the UWP?

Answer 1

You could set the opacity property of InkDrawingAttributesPencilProperties Class to achieve your target.

For example:

<InkCanvas x:Name="inkCanvas"></InkCanvas>

public MainPage()
{
    this.InitializeComponent();
    inkCanvas.InkPresenter.InputDeviceTypes =
        Windows.UI.Core.CoreInputDeviceTypes.Mouse |
        Windows.UI.Core.CoreInputDeviceTypes.Pen;

    InkDrawingAttributes pencilAttributes = InkDrawingAttributes.CreateForPencil();
    pencilAttributes.Color = Windows.UI.Colors.Red;
    pencilAttributes.Size = new Windows.Foundation.Size(3, 3);
    pencilAttributes.PencilProperties.Opacity = 0.5f;
    inkCanvas.InkPresenter.UpdateDefaultDrawingAttributes(pencilAttributes);
}