Migrate to a Swift Xcode project type

Migrate your existing Unity iOS project from the Objective-C project type to the new Swift project type.

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Last updated 22 days ago

Migrate your existing Unity iOS project from the Objective-C project type to the new Swift project type.

Considerations when migrating to a Swift Xcode project type

Consider the following before migrating to a Swift Xcode project type:

Exporting a project as a Swift Xcode project sets the minimum supported iOS version to 16. This applies even if your project's target version is lower.
Orientation handling during runtime behaves differently when using a Swift Xcode project type. For more information, refer to Manage screen orientation in Swift Xcode projects.
When migrating to a Swift Xcode project type, the following functionality isn't currently available:
- Unity as a Library
- Full screen video

Create a Swift Xcode project type

Use the following steps to create a Swift Xcode project type:

Navigate to Edit >
Project Settings
?
> Player.
Select the iOS tab.
From Other Settings > Configuration, set Xcode Project Type to Swift. This option is available for both iOS and tvOS.

Migrate post-process scripts for Swift Xcode projects

If you have post-process scripts that modify Xcode project files, you must update them to support changes to the project structure.

Update the project path

The Xcode project file now uses a sanitized version of your Unity project's name, rather than the static name

Unity-iPhone.xcodeproj

. To return the correct project path, use the

PBXProject.GetPBXProjectPath

method.

For example, update your code as follows:


// Before (Objective-C only):string projPath = Path.Combine(pathToBuiltProject, "Unity-iPhone.xcodeproj/project.pbxproj");// After (works for both Objective-C and Swift project types):string projPath = PBXProject.GetPBXProjectPath(pathToBuiltProject);

Review your existing modifications to the

.xcodeproj

file to ensure they're still required. For more information, refer to Structure of a Unity Xcode Swift project type.

Identify project types

To identify project types in your post-process scripts, use the

UnityEditor.PlayerSettings.xcodeProjectType

property. For example:


if (UnityEditor.PlayerSettings.xcodeProjectType == UnityEditor.XcodeProjectType.Swift) {    // Swift project type specific modifications} else {    // Objective-C project type specific modifications}

Migrate native plug-ins

With the introduction of the Swift project type, you must adapt your native plug-ins to work with the new UnityFramework and the updated Xcode project structure. This migration involves updating API calls, handling lifecycle events differently, and ensuring your plug-ins are correctly configured in the Unity Editor.

Configure plug-in compatibility

Ensure your plug-in is set to be included in the correct Xcode project type. By default, plug-ins are included in both the Objective-C and Swift project types. In the Unity Editor, open the Plugin Inspector for your native plug-in and review its platform settings to confirm the correct compatibility. For more information, refer to Configure a plug-in for iOS with the Inspector window.

Adapt to UnityFramework API changes

The contents of

UnityFramework

are different when using a Swift Xcode project type. Review your plug-in's dependencies and update any code that relies on functions or classes that are no longer available.

The

UnityPlayer

class now provides most of the functionality previously available through

UnityAppController

Note

UnityPlayer

isn't a direct substitute, so it's recommended to review the Swift project type API reference for details on its specific methods and properties.


// Before:UnityAppController* appController = GetAppController();// After (Swift):let player = UnityPlayer.shared// After (Objective-C):UnityPlayer *player = [UnityPlayer shared];

View and ViewController Access

To access the main rendering view and root view controller, use the properties on the

UnityPlayer

instance.


// Before:UIView* unityView = GetAppController().unityView;UIView* unityView = UnityGetUnityView();UIViewController* rootVC = GetAppController().rootViewController;UIViewController* rootVC = UnityGetGLViewController();// After (Swift):let unityView = UnityPlayer.shared.renderingViewlet rootVC = UnityPlayer.shared.rootViewController// After (Objective-C):UIView *unityView = [[UnityPlayer shared] renderingView];UIViewController *rootVC = [[UnityPlayer shared] rootViewController];

Pause and Resume

Pausing and resuming the application is now handled through methods on the

UnityPlayer

instance. For example:


// Before:if (!UnityIsPaused()) {    UnityPause(1);  // pause}UnityPause(0);  // resume// After (Swift):if (!UnityPlayer.shared.isPaused()) {    UnityPlayer.shared.pause()}UnityPlayer.shared.resume()// After (Objective-C):if (![[UnityPlayer shared] isPaused]) {    [[UnityPlayer shared] pause];}[[UnityPlayer shared] resume];

Migrate to NotificationCenter for lifecycle events

If your plug-in previously depended on

LifeCycleListener.h

AppDelegateListener

, you must migrate to using

NotificationCenter

to handle lifecycle events. The event definitions are now located in

UnityAPI/UnityPluginInterface/UnityNotifications.swift


// Before (using LifeCycleListener protocol):@interface MyPlugin : NSObject<AppDelegateListener>@end- (void)applicationWillFinishLaunchingWithOptions:(NSNotification*)notification { ... }// After (Swift):NotificationCenter.default.addObserver(    forName: UnityNotifications.applicationWillFinishLaunching,    object: nil, queue: nil) { _ in /* handle */ }// After (Objective-C):[[NSNotificationCenter defaultCenter]    addObserverForName:UnityNotifications.applicationWillFinishLaunching    object:nil queue:nil usingBlock:^(NSNotification *note) { /* handle */ }];

Available notifications include:

```
applicationWillFinishLaunching
```

applicationDidRegisterForRemoteNotifications

applicationDidFailToRegisterForRemoteNotifications

```
applicationDidReceiveRemoteNotification
```
```
unityDidQuit
```
```
unityDidUnload
```

applicationHandleEventsForBackgroundURLSession

```
sceneOpenURLContexts
```

UIApplication.didBecomeActiveNotification

UIApplication.didFinishLaunchingNotification

Note

To prevent duplicate notifications, Unity filters out certain lifecycle and app delegate events that iOS already provides, such as didFinishLaunchingNotification.

Call C# from native code

For the Swift project type, the recommended way to call into C# script is by using the

UnityPlayer.sendMessage()

method. The

UnitySendMessage()

C function is still available but now requires you to import

UnityPluginInterface.h


// Before (C/C++/Objective-C):UnitySendMessage("GameObjectName", "MethodName", "argument");// After (Swift):UnityPlayer.shared.sendMessage(toGameObject: "GameObjectName", method: "MethodName", argument: "argument")UnitySendMessage("GameObjectName", "MethodName", "argument")// After (Objective-C):#import "UnityPluginInterface.h"#import <UnityFramework/UnityFramework-Swift.h>[[UnityPlayer shared] sendMessageToGameObject:@"GameObjectName" method:@"MethodName" argument:@"argument"];UnitySendMessage("GameObjectName", "MethodName", "argument");// C/C++ still works (requires #import "UnityPluginInterface.h"):UnitySendMessage("GameObjectName", "MethodName", "argument");

Conditional Compilation

If you need to support both Xcode project types within the same plug-in source file, use the

UNITY_XCODE_PROJECT_TYPE_SWIFT

preprocessor macro to create different code paths.


#ifdef UNITY_XCODE_PROJECT_TYPE_SWIFT    UnityPlayer *player = [UnityPlayer shared];#else    UnityAppController* appController = GetAppController();#endif

Low level native plug-in API

The low-level native plug-in API remains the same, but the location of the header files has changed. The headers are now located in the

UnityAPI/UnityPluginInterface/

directory.

However, you can continue to import them in your code using the same syntax as before.

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