[Feature request] SplitablePanel - Panel with resizable children.

[ms-somanna]

Is your feature request related to a problem? Please describe. When I want to have multiple resizable and collapsible children in a parent I cannot use either a grid or a stackpanel (or uniform stacking panel, simple panel etc) because a grid has the functionality of resizing its children using a grid splitter but cannot expanded the visible child like a panel can when another child is collapsed. And using a panel instead of a grid would produce opposite results- a panel canot have a grid splitter like control to resize its children in the way the grid splitter can.

So my suggestion would be to implement a control that has the functionality of both the grid and stackpanel. Something like the one answered here and here