Xamarin.Forms - How to overlay an ActivityIndicator in the middle of a StackLayout programmatically

Question

I want to overlay my ActivityIndicator in the middle of my form but I\'m not entirely sure how I can go about this, I assume I need to wrap my stack layout in a relative lay

Answer 1

In code you can try this:

RelativeLayout relativeLayout = new RelativeLayout ();
StackLayout stack = new StackLayout ();
ActivityIndicator indicator = new ActivityIndicator ();

relativeLayout.Children.Add (stack);
relativeLayout.Children.Add (indicator);

RelativeLayout.SetBoundsConstraint (stack, () => relativeLayout.Bounds);

RelativeLayout.SetBoundsConstraint (indicator,
    BoundsConstraint.FromExpression (() =>  
        new Rectangle (relativeLayout.Width / 2 - 16, relativeLayout.Height / 2 - 16, 32, 32)));

Assuming width/height of the ActivityIndicator of 32/32, you can pick a size that fits your needs or calculate the size on the fly.

There still seem to be bugs in RelateiveLayout, it throws unexpected null pointer exceptions on occasion, even for solvable constraints