iOS AppDelegate UINotifications, in Unity MonoBehaviour scripts

AppDelegateLoudspeaker.cs

/// @creator: Slipp Douglas Thompson
/// @license: Public Domain per The Unlicense.  See <http://unlicense.org/>.
/// @why: Because this functionality should be built-into Unity.
/// @intended project path: Assets/Plugins/iOS-Bridge/AppDelegateLoudspeaker.cs
/// @intersource: https://gist.github.com/capnslipp/036f7c98f5ccf42e8428

using UnityEngine;



/// @note: Using direct 1-to-1 handlers/calls here (instead of a single method taking a string arg) for a few of reasons:
/// 	1. There's a fixed number of these and they'll change only infrequently, if ever.
/// 		• If notifications were to be added/removed, we'd have to also add/remove a method in AppDelegateLoudspeaker.m— and one parallel change per file seems pretty reasonable.
/// 	2. If bad something happens, we'll see the exact name of the notification in the backtrace.
/// 	3. The C# compiler [should be able to] optimize these non-variable use-cases better, which is important because we already know the `ComponentBroadcastAllExtension.BroadcastAllMessage()` call is spendy.
static class AppDelegateLoudspeaker
{
	// Native-Side Notification Handlers
	
	static void _BroadcastUIApplicationDidRegisterForRemoteNotificationsNotification() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationDidRegisterForRemoteNotificationsNotification");
	}
	static void _BroadcastUIApplicationDidFailToRegisterForRemoteNotificationsNotification() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationDidFailToRegisterForRemoteNotificationsNotification");
	}
	static void _BroadcastUIApplicationDidReceiveRemoteNotificationNotification() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationDidReceiveRemoteNotificationNotification");
	}
	static void _BroadcastUIApplicationDidReceiveLocalNotificationNotification() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationDidReceiveLocalNotificationNotification");
	}
	static void _BroadcastUIApplicationDidOpenURL() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationDidOpenURL");
	}
	static void _BroadcastUIApplicationDidReceiveMemoryWarningNotification() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationDidReceiveMemoryWarningNotification");
	}
	static void _BroadcastUIApplicationSignificantTimeChangeNotification() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationSignificantTimeChangeNotification");
	}
	static void _BroadcastUIApplicationWillChangeStatusBarFrameNotification() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationWillChangeStatusBarFrameNotification");
	}
	static void _BroadcastUIApplicationWillChangeStatusBarOrientationNotification() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationWillChangeStatusBarOrientationNotification");
	}
	static void _BroadcastUIApplicationDidFinishLaunchingNotification() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationDidFinishLaunchingNotification");
	}
	static void _BroadcastUIApplicationDidBecomeActiveNotification() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationDidBecomeActiveNotification");
	}
	static void _BroadcastUIApplicationWillResignActiveNotification() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationWillResignActiveNotification");
	}
	static void _BroadcastUIApplicationDidEnterBackgroundNotification() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationDidEnterBackgroundNotification");
	}
	static void _BroadcastUIApplicationWillEnterForegroundNotification() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationWillEnterForegroundNotification");
	}
	static void _BroadcastUIApplicationWillTerminateNotification() {
		ComponentBroadcastAllExtension.BroadcastAllMessage("OnUIApplicationWillTerminateNotification");
	}
}

AppDelegateLoudspeaker.h

/// @creator: Slipp Douglas Thompson
/// @license: Public Domain per The Unlicense.  See <http://unlicense.org/>.
/// @why: Because this functionality should be built-into Unity.
/// @intended project path: Assets/Plugins/iOS/AppDelegateLoudspeaker.h
/// @intersource: https://gist.github.com/capnslipp/036f7c98f5ccf42e8428
#pragma once

#include "PluginBase/AppDelegateListener.h"



@interface AppDelegateLoudspeaker : NSObject<AppDelegateListener>
@end

AppDelegateLoudspeaker.m

/// @creator: Slipp Douglas Thompson
/// @license: Public Domain per The Unlicense.  See <http://unlicense.org/>.
/// @why: Because this functionality should be built-into Unity.
/// @intended project path: Assets/Plugins/iOS/AppDelegateLoudspeaker.m
/// @intersource: https://gist.github.com/capnslipp/036f7c98f5ccf42e8428

#import "AppDelegateLoudspeaker.h"



#pragma mark Mono Type and Function Prototypes/Forward Declarations

typedef void* MonoDomain;
typedef void* MonoAssembly;
typedef void* MonoImage;
typedef void* MonoClass;
typedef void* MonoObject;
typedef void* MonoMethodDesc;
typedef void* MonoMethod;
typedef void* gpointer;
typedef int gboolean;

MonoDomain * mono_domain_get();
MonoAssembly * mono_domain_assembly_open(MonoDomain *domain, const char *assemblyName);
MonoImage * mono_assembly_get_image(MonoAssembly *assembly);
MonoMethodDesc * mono_method_desc_new(const char *methodString, gboolean useNamespace);
MonoMethodDesc * mono_method_desc_free(MonoMethodDesc *desc);
MonoMethod * mono_method_desc_search_in_image(MonoMethodDesc *methodDesc, MonoImage *image);
MonoObject * mono_runtime_invoke(MonoMethod *method, void *obj, void **params, MonoObject **exc);
gpointer mono_object_unbox(MonoObject *obj);



#pragma mark AppDelegateLoudspeaker

@interface AppDelegateLoudspeaker () {
	MonoImage *_monoImage;
}

- (MonoImage *)fetchMonoImage;

@end


@implementation AppDelegateLoudspeaker


#pragma mark Create/Destroy

- (id)init
{
	self = [super init];
	if (!self)
		return nil;
	
	_monoImage = [self fetchMonoImage];
	
	UnityRegisterAppDelegateListener(self);
	
	return self;
}

- (MonoImage *)fetchMonoImage
{
	MonoDomain *domain = mono_domain_get();
	NSString *assemblyPath = [NSBundle.mainBundle.bundlePath stringByAppendingPathComponent:@"Data/Managed/Assembly-CSharp-firstpass.dll"];
	MonoAssembly *assembly = mono_domain_assembly_open(domain, assemblyPath.UTF8String);
	MonoImage *image = mono_assembly_get_image(assembly);
	return image;
}

- (void)dealloc
{
	UnityUnregisterAppDelegateListener(self);
	
	_monoImage = NULL;
	
	#if !__has_feature(objc_arc)
		[super dealloc];
	#endif
}


#pragma mark Util

/// @arg methodName: The title-case name the notification method on the C#-side AppDelegateLoudspeaker class.
- (void)monoInvokeLoudspeakerNotification:(NSString *)notificationName
{
	NSString *methodDescStr = [[NSString alloc] initWithFormat:@"%@:_Broadcast%@()", NSStringFromClass(self.class), notificationName];
	MonoMethodDesc *methodDesc = mono_method_desc_new(methodDescStr.UTF8String, FALSE);
	
	MonoMethod *method = mono_method_desc_search_in_image(methodDesc, _monoImage);
	
	mono_method_desc_free(methodDesc);
	#if !__has_feature(objc_arc)
		[methodDescStr release];
	#endif
	
	mono_runtime_invoke(method, NULL /* obj */, NULL /* params */, NULL /* exc */);
}


#pragma mark AppDelegateListener Handlers

- (void)didRegisterForRemoteNotificationsWithDeviceToken:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationDidRegisterForRemoteNotificationsNotification"];
}
- (void)didFailToRegisterForRemoteNotificationsWithError:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationDidFailToRegisterForRemoteNotificationsNotification"];
}
- (void)didReceiveRemoteNotification:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationDidReceiveRemoteNotificationNotification"];
}
- (void)didReceiveLocalNotification:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationDidReceiveLocalNotificationNotification"];
}
- (void)onOpenURL:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationDidOpenURL"];
}
- (void)applicationDidReceiveMemoryWarning:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationDidReceiveMemoryWarningNotification"];
}
- (void)applicationSignificantTimeChange:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationSignificantTimeChangeNotification"];
}
- (void)applicationWillChangeStatusBarFrame:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationWillChangeStatusBarFrameNotification"];
}
- (void)applicationWillChangeStatusBarOrientation:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationWillChangeStatusBarOrientationNotification"];
}


#pragma mark LifeCycleListener Handlers

- (void)didFinishLaunching:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationDidFinishLaunchingNotification"];
}
- (void)didBecomeActive:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationDidBecomeActiveNotification"];
}
- (void)willResignActive:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationWillResignActiveNotification"];
}
- (void)didEnterBackground:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationDidEnterBackgroundNotification"];
}
- (void)willEnterForeground:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationWillEnterForegroundNotification"];
}
- (void)willTerminate:(NSNotification*)notification {
	[self monoInvokeLoudspeakerNotification:@"UIApplicationWillTerminateNotification"];
}


@end

ComponentBroadcastAllExtension.cs

/// @creator: Slipp Douglas Thompson
/// @license: Public Domain per The Unlicense.  See <http://unlicense.org/>.
/// @why: Because this functionality should be built-into Unity.
/// @intended project path: Assets/Plugins/UnityEngine Extensions/ComponentBroadcastAllExtensions.cs
/// @intersource: https://gist.github.com/capnslipp/036f7c98f5ccf42e8428

using System.Collections.Generic;
using System.Linq;
using UnityEngine;
using UObject=UnityEngine.Object;



public static class ComponentBroadcastAllExtension
{
	/// @todo: Profile to see if it would be better to just SendMessage to every Transform rather than Where for the roots.
	static Transform[] GetAllRootTransforms()
	{
		Transform[] allTransforms = UObject.FindObjectsOfType<Transform>();
		Transform[] rootTransforms = new List<Transform>(allTransforms).Where(t => (t.parent == null)).ToArray();
		return rootTransforms;
	}
	
	/// Rather expensive (because of GetAllRootTransforms()).  Use sparingly.
	public static void BroadcastAllMessage(this Component @this, string methodName) {
		BroadcastAllMessage(methodName);
	}
	/// Rather expensive (because of GetAllRootTransforms()).  Use sparingly.
	/// Assumes SendMessageOptions.DontRequireReceiver because checking if any one of the root GameObjects has it would be a PitA (because Unity doesn't use normal catchable exceptions).
	public static void BroadcastAllMessage(string methodName)
	{
		Component[] roots = GetAllRootTransforms();
		
		foreach (Component root in roots)
			root.BroadcastMessage(methodName, SendMessageOptions.DontRequireReceiver);
	}
}

UsageExample.cs

using UnityEngine;



public class UsageExample : MonoBehaviour
{
	void OnUIApplicationWillResignActiveNotification()
	{
		Debug.Log("UIApplicationWillResignActiveNotification!");
	}
}