Compact overlay should allow resizing

[BreeceW]

Proposal: Compact overlay should allow resizing

Summary

The new CompactOverlayPresenter is described as “an ‘always on top’ window of a fixed size, with a 16:9 aspect ratio to allow for Picture-in-Picture like experiences.” There are three options for the initial size of the window, “Small,” “Medium,” and “Large,” however the size seems to be overridable by calling Resize on AppWindow. The user cannot resize the window via dragging its edges, nor is there an option to allow this.

Compact overlay windows should be resizable by the user to any size and aspect ratio by default, with APIs to configure this.

Rationale

• The UWP compact overlay allowed a custom initial size and always lets the user resize it
• Compact overlay isn’t just used for video (see Windows Calculator)
• Greater flexibility for both developer and user

Scope

Capability	Priority
This proposal will allow end users to freely resize compact overlay windows	Must
This proposal will allow developers to specify whether windows can be resized	Could

Important Notes

var presenter = CompactOverlayPresenter.Create();
presenter.InitialSize = CompactOverlaySize.Medium;
presenter.InitialSize = new CompactOverlaySize(300, 400);
presenter.ResizeMode = CompactOverlayResizeMode.Free; // Free should be default
presenter.ResizeMode = CompactOverlayResizeMode.Fixed; // This could be a Boolean CanResize
window.SetPresenter(presenter);

Alternatively, window could just have a CanResize property, and compact overlay would just follow that.

UWP let users resize compact overlay windows, but only within a range specified by the system. This is arbitrary and not particularly helpful. There should not be a limit anymore, or the limit should be specified by the developer.

Resizing from the corners should preserve the aspect ratio (perhaps optionally). This is useful for the video scenario without negating the others too much. Resizing from the edges would allow the user to make the window any size they please. This is how it works in UWP today.

If the existing InitialSize is there to provide good defaults for videos, I support that, but it is important that you be able to open a compact overlay window at any size as well and be able to resize it later.

Open Questions

Is it even a good idea to make windows fixed size? This is probably almost always going to result in poor user experience.
Should sizing APIs be on the presenter at all? Why not allow compact overlay windows to be resizable, and if a developer wants to make them fixed, they could specify that on AppWindow?

[martibravo]

I believe that you would be better served by an OverlappedPresenter: (as a temporary workaround)

Set its properties IsMaximizable and IsMinimizable to false and AppWindowTitlebar.ExtendsContentIntoTitlebar to true you'll get a resizable Picture-in-Picture window without a title nor max/min buttons and it will not be snappable with Snap Layouts.

//other includes
using Microsoft.UI.Windowing;
using Microsoft.UI.Xaml.Interop;
using System.Runtime.InteropServices.WindowsRuntime;

//namespace and other code

public sealed partial class MainWindow : Window
    {
        private AppWindow _apw;
        private OverlappedPresenter _presenter;
        
        public MainWindow()
        {
            this.InitializeComponent();
            GetAppWindowAndPresenter();
            _presenter.IsMaximizable = false;
            _presenter.IsMinimizable = false;
            _apw.TitleBar.ExtendsContentIntoTitleBar = true;
        }

        private void myButton_Click(object sender, RoutedEventArgs e)
        {
            myButton.Content = "Clicked";
        }

        public void GetAppWindowAndPresenter()
        {
            var hWnd = WinRT.Interop.WindowNative.GetWindowHandle(this);
            WindowId myWndId = Win32Interop.GetWindowIdFromWindow(hWnd);
            _apw = AppWindow.GetFromWindowId(myWndId);
            _presenter = _apw.Presenter as OverlappedPresenter;
        }
    }

[emhuang-msft]

tracked by http://task.ms/38044671