Display a modal page as a popover on iOS and Mac Catalyst

This .NET Multi-platform App UI (.NET MAUI) iOS platform-specific is used to display a modal page as a popover. It's consumed by setting the Page.ModalPopoverSourceView bindable property to a View, the Page.ModalPopoverRect bindable property to a Rectangle, and the Page.ModalPresentationStyle bindable property to UIModalPresentationStyle.Popover. This can be achieved in C# using the fluent API:

using Microsoft.Maui.Controls.PlatformConfiguration;
using Microsoft.Maui.Controls.PlatformConfiguration.iOSSpecific;
...

public partial class PopoverPage : ContentPage
{
    public PopoverPage(View modal, Rectangle rectangle)
    {
        InitializeComponent();
        On<iOS>().SetModalPopoverView(modal);
        On<iOS>().SetModalPopoverRect(rectangle);
        On<iOS>().SetModalPresentationStyle(UIModalPresentationStyle.Popover);
    }
}

The Page.On<iOS> method specifies that this platform-specific will only run on iOS. The Page.SetModalPopoverView method, in the Microsoft.Maui.Controls.PlatformConfiguration.iOSSpecific namespace, is used to set the source view of the popover. The Page.SetModalPopoverRect method is used to set the rectangle within the view from which the popover will originate. The Page.SetModalPresentationStyle method is used to set the modal presentation style to popover by specifying the UIModalPresentationStyle.Popover enumeration value.

Pages that use this platform-specific to display a modal page as a popover must use modal navigation:

Page modalPage = new PopoverPage(originButton, Rectangle.Empty);
await Navigation.PushModalAsync(modalPage);

For more information about modal navigation, see Perform modal navigation.