Very simple test of writing a native iOS plugin for unity
Loosely following the instructions here.
- Make a simple Unity project (this one's called "IOSPluginTestUnity") and add a cube to the main scene.
- Build a Cocoa Touch Static Library in Xcode (this one's called "IOSPluginTest").
- Place the .a file that results from building the Xcode project into an Assets/Plugins/iOS directory in the Unity project.
- Write a script and attach it to the cude in the main scene. Use it to call the native iOS and set the colour of the cube depending on the result of the call.
- Build & run the Unity project for iOS. This generates another Xcode project (this one's called "IOSPluginTestUnityXcode").
- Build, deploy, and run the project on the iPhone. I needed to fix the signing team first. And later I needed to change the build target to > 8 (I went for 10.2).
The commit afdf67 contains just one simple call from the Unity C# script into the iOS native C++ code.
Commit c99815 incudes a callback from the iOS native C++ code into the Unity C# script.
Then commit 32cea6 goes back to the simple call (without a callback). But the call from the Unity C# script into the iOS native C++ then calls further into an instance method on an Objective-C object.
The code in 05f4e4 adds a callback from the Objective-C back into the Unity C# script.
For commit b4f22f I am back to a very simple call from a Unity C# script but this time it is into a Mono C# DLL.
Extending that, commit 7ef0fc has a Unity C# script calling into a Mono C# DLL which in turn calls into the native iOS static library, and includes a callback from the native iOS static library to the Mono C# DLL.
The code in commit 963fb0 should look no different from the code in the previous commit, but the Mono DLL and the native iOS static library were added to the Unity project by importing a Unity package (called MonoTestPackage.unitypackage in the IOSPluginTestUnity directory). The package was created following the instructions in the Unity manual here.
I'll end with a wee experiment. If I do away with the Mono DLL and the iOS static library and just include their files directly in Unity will it still work? Yes. This version has the Mono DLL and the native iOS static library deleted and the Calculations.cs file from the Mono DLL placed in Assets/Scripts and the files IOSPluginTest.h and IOSPluginTest.m from the iOS static library placed in Assets/Plugins/iOS.