FrameworkElement的HorizontalAlignment/VerticalAlignment与Android的fill_parent/wrap_conte

rameworkElement.HorizontalAlignment Property:
A horizontal alignment setting, as a value of the enumeration. The default is Stretch.

FrameworkElement.VerticalAlignment Property:
A vertical alignment setting. The default is Stretch.

默认是Stretch，类似Android的fill_parent，
非Stretch，类似Android的wrap_content。