xamarin-android-button-left-image.cs

private void SetLeftDrawableWithBounds(Button button, int drawableResId, Size size, Android.Graphics.Color tintColor) {
    var context = button.Context;
    var drawable = DrawableCompat.Wrap(AppCompatDrawableManager.Get().GetDrawable(context, drawableResId)).Mutate();
    drawable.SetBounds(0, 0, (int) context.ToPixels(size.Width), (int) context.ToPixels(size.Height));

    if (tintColor != Android.Graphics.Color.Transparent) {
        DrawableCompat.SetTint(drawable, tintColor);
    }

    button.SetCompoundDrawables(drawable, null, null, null);
}