Multiple windows for iPad
iOS 13 now supports side-by-side windows for the same app on iPad. This enables new experiences and drag-and-drop interactions between windows. This document shows you how to setup your application to support this feature, and introduces these new features.
Project Configuration
To configure your project for multiple windows, amend the info.plist to declare NSUserActivityTypes telling iOS your app will handle activities of this type, and UIApplicationSceneManifest to enable UIApplicationSupportsMultipleScenes for multiple windows and UISceneConfigurations to associate your scene with a storyboard.
<key>NSUserActivityTypes</key>
<array>
<string>com.xamarin.Gallery.openDetail</string>
</array>
<key>UIApplicationSceneManifest</key>
<dict>
<key>UIApplicationSupportsMultipleScenes</key>
<true/>
<key>UISceneConfigurations</key>
<dict>
<key>UIWindowSceneSessionRoleApplication</key>
<array>
<dict>
<key>UISceneConfigurationName</key>
<string>Default Configuration</string>
<key>UISceneDelegateClassName</key>
<string>SceneDelegate</string>
<key>UISceneStoryboardFile</key>
<string>Main</string>
</dict>
</array>
</dict>
</dict>
Opening Multiple Windows
With your app open and running on an iPad, there are a few ways to open multiple windows of that app that iOS handles be default.
- App Expose - tap the app icon in the dock to enter this mode while your app is open.
- Slide Over - drag the app icon from the dock over the top of your running app to have a floating window.
- Split Screen - drag the app icon from the dock to the edge of the iPad screen to create a new side-by-side window.
Additional interactions to enter a multiple window mode are available from within your application.
Drag from App - use a drag interaction within your app to start a new NSUserActivity just like dragging your app icon in previous examples.
When using a drag-and-drop interaction, you create an NSUserActivity and associate the data to be passed along to the new window you're asking iOS to open for you.
public UIDragItem [] GetItemsForBeginningDragSession (UICollectionView collectionView, IUIDragSession session, NSIndexPath indexPath)
{
var selectedPhoto = GetPhoto (indexPath);
var userActivity = selectedPhoto.OpenDetailUserActivity ();
var itemProvider = new NSItemProvider (UIImage.FromFile (selectedPhoto.Name));
itemProvider.RegisterObject (userActivity, NSItemProviderRepresentationVisibility.All);
var dragItem = new UIDragItem (itemProvider) {
LocalObject = selectedPhoto
};
return new [] { dragItem };
}
In the code above, the selectedPhoto model object has a method to return an NSUserActivity called OpenDetailUserActivity(). When the drag gesture is complete, the UIDragItem with present the userActivity via the NSItemProvider.
Explicit Actions - user gestures on buttons or links offer the ability to open a new window.
From the UIApplication you can start a new UISceneSession by calling RequestSceneSessionActivation. If an existing scene already exists, you should use that. By default a new scene will be created for you.
public void ItemSelected(UICollectionView collectionView, NSIndexPath indexPath)
{
var userActivity = selectedPhoto.OpenDetailUserActivity ();
UIApplication.SharedApplication.RequestSceneSessionActivation(
sceneSession: null,
userActivity: userActivity,
options: null,
errorHandler: null
);
}
In this example, the userActivity is the only value passed to the RequestSceneSessionActivation method in order to open a new window of the application based on an explicit user action; in this case an ItemSelected handler of a UICollectionView.