Re-introduce the repositionable modal Window (Dialog Box)

[fabianoriccardi]

This discussion is to propose the repositionable modal Dialog Window as used to be in previous frameworks (WPF and WinForm). The most notable example of what I would implement is the Options window in Visual Studio 2022.
I think this kind of window is convenient for windows that requires full user attention, but since they contain a lot of fields, they deserve a full-featured window (movable and resizable). So, the current ContentDialog is not enough for this scenario.

There is already a feature request in WinAppSDK 1.7 Plans, but in case it won't be implemented in next release, this discussion won't expire.

A related feature that can be useful to implement this is already discussed here, but at current state, I didn't find a method to create and populate a window with the aforementioned requirements.

[castorix]

You can make ContentDialog movable and resizable
A test with ManipulationDelta to move it and PointerPressed, PointerMoved, ... on a child rectangle to resize (mouse cursor should be modyfied too... or a better method) (I changed the Template in App.xaml to add a red border) :

[fabianoriccardi]

Great, but it doesn't look like a common window...

[castorix]

Great, but it doesn't look like a common window...

Because I updated the Template of ContentDialog (Grid + Border) for the test