Unity与iOS交互

• Unity调用iOS的方法，首先在Xcode中新建一个iOS的桥接类，并且将.m的后缀修改为.mm

• 在.h中加入以下代码，里面的函数包括 无返回，返回字符串，返回布尔，带参数的函数等
  这里需要注意一个问题，传入的参数和返回的字符串最好都使用json格式

#if defined(__cplusplus)
extern "C"{
#endif
    // 获取系统语言
    extern char *GetLanguage();
    // 开始震动
    extern void StartVibration(char *param);
    // 是否是全面屏
    extern bool IsFullSecreen();
    // Unity iOS 字符串内存管理
    extern char* CharMemoryManagement(NSString *param);
#if defined(__cplusplus)
}
#endif

• 在.mm中的实现，这里需要注意的是，返回字符串的时候，只能通过CharMemoryManagement方法将字符串转换成char，我试过其他很多种转换方式，都会造成程序崩溃的问题，Tools类里面就是方法的具体实现，代码与本文无关就不贴出来了

#if defined(__cplusplus)
extern "C"{
#endif
    char *GetLanguage()
    {
        NSString *str = [Tools GetLanguage];
        return CharMemoryManagement(str);
    }
    void StartVibration(char *param)
    {
        [Tools StartVibration:[NSString stringWithUTF8String:param]];
    }
    bool IsFullSecreen()
    {
        return [Tools IsFullSecreen];
    }
    // 如果方法返回的是字符串，需要使用该方法将字符串转为char
    char* CharMemoryManagement(NSString *text)
    {
        char* ret = nullptr;
        ret = (char*) malloc([text length] + 1);
        memcpy(ret,[text UTF8String],([text length] + 1));
        return ret;
    }
#if defined(__cplusplus)
}
#endif

• 上面的步骤完成之后，将.h和.mm文件(包括Tools等依赖的文件)拷贝到Unity工程中Assets目录下
• 在Unity中，新建一个cs脚本，添加以下代码，这个脚本最好实现成单例，然后就可以通过Instance.IOSGetLanguage()来调用
  注意需要引用 using System.Runtime.InteropServices 命名空间

#if UNITY_IOS && !UNITY_EDITOR
    [DllImport("__Internal")] private static extern string GetLanguage();
    [DllImport("__Internal")] private static extern bool IsFullSecreen();
    [DllImport("__Internal")] private static extern void StartVibration(string param);
#endif

#region Unity to iOS
    public string IOSGetLanguage()
    {
#if UNITY_IOS && !UNITY_EDITOR
        return GetLanguage();
#else
        return "";
#endif
    }
    public void IOSStartVibration(long time)
    {
#if UNITY_IOS && !UNITY_EDITOR
        StartVibration(time.ToString());
#endif
    }
    public bool IOSIsFullSecreen()
    {
#if UNITY_IOS && !UNITY_EDITOR
        return IsFullSecreen();
#else
        return false;
#endif
    }

• iOS通知Unity，iOS直接调用Unity方法的实现是非常麻烦的，通常情况下，我们都使用通知的方法，常见的场景是Unity调用iOS方法需要异步返回时
• 在iOS类中加入下面代码，然后我们就可以给Unity发送通知了，如UnitySendMessage("节点名称", "方法名称", "参数，没有就传空字符串"",不能传nil")

// --------- 某个.mm文件中 ---------
#if defined(__cplusplus)
extern "C"{
#endif
    extern void UnitySendMessage(const char *, const char *, const char *);
#if defined(__cplusplus)
}
#endif

// --------- 需要通知Unity的iOS类中 ---------
- (void)didReceiveReward {
    // 在iOS的某个方法中，向Unity发送消息
    UnitySendMessage("iOSLibraryUnity", "OnDidReceiveReward", "收到奖励");
}

//  --------- Unity中挂在节点上的脚本，用来接收通知 ---------
private void Start()
{
    // 脚本挂载的节点名必须和UnitySendMessage发送时填的一样
    this.name = "iOSLibraryUnity";
}
private void OnDidReceiveReward(string msg)
{
    // 接收到iOS通知
    Debug.log(msg);
}

Unity脚本修改Xcode工程

Unity要在iOS平台发布，需要先生成Xcode工程，通常生成Xcode工程后我们还需要修改很多的配置，添加原生代码等， 而这些是可以通过cs脚本修改的，比如修改Xcode工程的plist、添加Framework库、拷贝文件到iOS工程、插入代码等

• 自动pod
  实现自动pod需要谷歌的一个插件https://github.com/googlesamples/unity-jar-resolver，该插件在谷歌相关的一些SDK中就有，如OnsSignal、Firebase等SDK，如你应用集成有这些SDK，则不需要再下载该插件了，查看是否集成了该插件可以看你Assets目录下有没有ExternalDependencyManager文件，或看Assets->External Dependency Manager有没有这个选项
• 集成完插件后，在Editor目录下新建一个Dependencies.xml的文件，里面的内容如下，这样在生成Xcode工程时就会自动将下面的库pod进工程

<dependencies>
  <iosPods>
    <iosPod name="AFNetworking" version="4.0.1"/>
    <iosPod name="SDWebImage" version="5.8.4"/>
    <iosPod name="Masonry" version="1.1.0"/>
    <iosPod name="YYModel" version="1.0.4"/>
  </iosPods>
</dependencies>

• 修改Xcode工程，在Editor中新建一个cs脚本，如下

using UnityEditor;
using UnityEditor.Callbacks;
using UnityEditor.iOS.Xcode;
using UnityEditor.XCodeEditor;

public static class BuildiOS
{
    [PostProcessBuild(100)]
    public static void OnPostprocessBuild(BuildTarget buildTarget, string buildPath)
    {
        if (buildTarget != BuildTarget.iOS)
            return;
        var mProjectPath = PBXProject.GetPBXProjectPath(buildPath);
        var mProject = new PBXProject();
        mProject.ReadFromString(File.ReadAllText(mProjectPath));

        var mTargetGUID = GetPBXProjectTargetGUID(mProject);
        var mFrameworkGUID = GetPBXProjectUnityFrameworkGUID(mProject);

        var mPlistPath = Path.Combine(buildPath, "Info.plist");

        // 修改Plist
        PlistModify(mPlistPath);

        // 添加系统库
        SystemFrameworkAdd(mProject, mFrameworkGUID);

        // 添加文件
        FilesAdd(mProject, mTargetGUID, buildPath, mProjectPath);

        // 插入代码
        UnityAppControllerCodesAdd(buildPath);
    }

#if UNITY_2019_3_OR_NEWER
    private static string GetPBXProjectTargetGUID(PBXProject project)
    {
        return project.GetUnityMainTargetGuid();
    }
    private static string GetPBXProjectUnityFrameworkGUID(PBXProject project)
    {
        return project.GetUnityFrameworkTargetGuid();
    }
#else
    private static string GetPBXProjectTargetGUID(PBXProject project)
    {
        return project.TargetGuidByName(PBXProject.GetUnityTargetName());
    }
    private static string GetPBXProjectUnityFrameworkGUID(PBXProject project)
    {
        return GetPBXProjectTargetGUID(project);
    }
#endif
}

• 修改plist

private static void PlistModify(string plistPath)
{
    var plist = new PlistDocument();
    plist.ReadFromFile(plistPath);

    // plist中添加一个字符串类型的key 如隐私设置
    plist.root.SetString("NSLocationAlwaysAndWhenInUseUsageDescription",
                         "$(PRODUCT_NAME) needs to get the location. I hope you agree.";

    // plist中添加一个布尔的key
    plist.root.SetBoolean("CADisableMinimumFrameDuration", false);

    // plist中添加一个字典的key 如ATS设置
    PlistElementDict dict = plist.root.CreateDict("NSAppTransportSecurity");
    dict.SetBoolean("NSAllowsArbitraryLoads", true);
        
    // 最后保存plist
    plist.WriteToFile(plistPath);
}

• 添加系统库

private static void SystemFrameworkAdd(PBXProject project, string mFrameworkGUID) 
{
    string[] FRAMEWORKS_TO_ADD = {
        "libz.dylib",
        "libc++.dylib",
        "Security.framework",
        "SystemConfiguration.framework",
    };
    foreach (var framework in FRAMEWORKS_TO_ADD)
    {
        project.AddFrameworkToProject(mFrameworkGUID, framework, false);
    }
}
private static void SystemLibAdd(PBXProject project, string targetGuid, string lib)
{
    string fileGuid = project.AddFile("usr/lib/" + lib, "Frameworks/" + lib, PBXSourceTree.Sdk);
    project.AddFileToBuild(targetGuid, fileGuid);
}

• 拷贝文件夹，代码文件如.h/.m等文件会自动拷贝的Xcode工程中，但图片，三方的Framework、lib等文件并不会自动拷贝到Xcode工程中，所以需要cs脚本来完成

private static void FilesAdd(PBXProject project, string mTargetGUID, string buildPath, string projectPath)
{
    string ResourcePath = "Assets/文件夹路径";
    XcodeDirectoryProcessor copy = new XcodeDirectoryProcessor();
    copy.CopyAndAddBuildToXcode(project, mTargetGUID, ResourcePath, buildPath, "Xcode中的文件夹名称");
    File.WriteAllText(projectPath, project.WriteToString());
}

• 插入代码

private static void UnityAppControllerCodesAdd(string buildPath)
{
    // 获取Prefix.pch文件
    string mPchPath = buildPath + "/Classes/Prefix.pch";
    UnityEditor.XCodeEditor.XClass Pch = new UnityEditor.XCodeEditor.XClass(mPchPath);
    // 需要插入的代码，例如我们在pch中插入一段引入类的代码
    string call = "#import \"output.h\"";
    // 代码标记，找到pch文件里面已经存在的代码，我们就可以将需要插入的代码，插入到这行代码下面
    string mark = "#include \"UnityInterface.h\"";
    // 开始插入代码
    Pch.WriteBelow(mark, call);
}

• 其他Editor中使用到的cs文件

using UnityEngine;
using System.IO;

#if UNITY_IOS
using UnityEditor.iOS.Xcode;

public static class ExtensionName
{
    public const string META = ".meta";
    public const string ARCHIVE = ".a";
    public const string FRAMEWORK = ".framework";
    public const string BUNDLE = ".bundle";
}

public class XcodeDirectoryProcessor {

    /// <summary>
    /// 添加编译本地文件到Xcode工程
    /// </summary>
    /// <param name="pbxProject"></param>
    /// <param name="targetGuid"></param>
    /// <param name="copyDirectoryPath">源路径</param>
    /// <param name="buildPath">拷贝路径</param>
    /// <param name="currentDirectoryPath">拷贝路径/currentDirectoryPath</param>
    /// <param name="needToAddBuild"></param>
    public void CopyAndAddBuildToXcode(PBXProject pbxProject, string targetGuid, string copyDirectoryPath, string buildPath, string currentDirectoryPath, bool needToAddBuild = true){

        string unityDirectoryPath = copyDirectoryPath;
        string xcodeDirectoryPath = buildPath;

        if(!string.IsNullOrEmpty(currentDirectoryPath)){
            unityDirectoryPath = Path.Combine(unityDirectoryPath, currentDirectoryPath);
            xcodeDirectoryPath = Path.Combine(xcodeDirectoryPath, currentDirectoryPath);
            Delete (xcodeDirectoryPath);
            Directory.CreateDirectory(xcodeDirectoryPath);
        }
        foreach (string filePath in Directory.GetFiles(unityDirectoryPath)){
            string extension = Path.GetExtension (filePath);
            if(extension == ExtensionName.META){
                continue;
            }
            else if(extension == ExtensionName.ARCHIVE){
                pbxProject.AddBuildProperty(
                    targetGuid, 
                    "LIBRARY_SEARCH_PATHS", 
                    "$(PROJECT_DIR)/" + currentDirectoryPath
                );
            }
            string fileName = Path.GetFileName (filePath);
            string copyPath = Path.Combine (xcodeDirectoryPath, fileName);
            if(fileName[0] == '.'){
                continue;
            }
            File.Delete(copyPath);
            File.Copy(filePath, copyPath);
            if(needToAddBuild){
                string relativePath = Path.Combine(currentDirectoryPath, fileName);
                pbxProject.AddFileToBuild(targetGuid, pbxProject.AddFile(relativePath, relativePath, PBXSourceTree.Source));
            }
        }
        //遍历文件夹
        foreach (string directoryPath in Directory.GetDirectories(unityDirectoryPath)){
            string directoryName = Path.GetFileName (directoryPath);
            bool nextNeedToAddBuild = needToAddBuild;
            if(directoryName.Contains(ExtensionName.FRAMEWORK) || directoryName.Contains(ExtensionName.BUNDLE) || 
               directoryName == "Unity-iPhone"){
                nextNeedToAddBuild = false;
            }
            CopyAndAddBuildToXcode (
                pbxProject, targetGuid, 
                copyDirectoryPath, buildPath, Path.Combine(currentDirectoryPath, directoryName), 
                nextNeedToAddBuild
            );
            if(directoryName.Contains(ExtensionName.FRAMEWORK) || directoryName.Contains(ExtensionName.BUNDLE)){
                string relativePath = Path.Combine(currentDirectoryPath, directoryName);
                pbxProject.AddFileToBuild(targetGuid, pbxProject.AddFile(relativePath, relativePath, PBXSourceTree.Source));
                pbxProject.AddBuildProperty(
                    targetGuid, 
                    "FRAMEWORK_SEARCH_PATHS", 
                    "$(PROJECT_DIR)/" + currentDirectoryPath
                );
            }
        }
    }

    /// <summary>
    /// 拷贝目录（拷贝时候会删除copyPath）
    /// </summary>
    /// <param name="sourcePath"></param>
    /// <param name="copyPath"></param>
    public void CopyAndReplace(string sourcePath, string copyPath)
    {
        Delete (copyPath);
        Directory.CreateDirectory(copyPath);
        foreach (var file in Directory.GetFiles(sourcePath)){
            File.Copy(file, Path.Combine(copyPath, Path.GetFileName(file)));
        }
        foreach (var dir in Directory.GetDirectories(sourcePath)){
            CopyAndReplace(dir, Path.Combine(copyPath, Path.GetFileName(dir)));
        }
    }

    /// <summary>
    /// 删除目录
    /// </summary>
    /// <param name="targetDirectoryPath"></param>
    public void Delete(string targetDirectoryPath){
        if (!Directory.Exists (targetDirectoryPath)) {
            return;
        }
        string[] filePaths = Directory.GetFiles(targetDirectoryPath);
        foreach (string filePath in filePaths){
            File.SetAttributes(filePath, FileAttributes.Normal);
            File.Delete(filePath);
        }
        string[] directoryPaths = Directory.GetDirectories(targetDirectoryPath);
        foreach (string directoryPath in directoryPaths){
            Delete(directoryPath);
        }
        Directory.Delete(targetDirectoryPath, false);
    }
}

#endif