Android笔记(二十五)：两种sdk热更插件资源加载方案

背景

在研究sdk插件化热更新方式的过程中总结出了两套插件资源加载方案，在此记录下

资源热更方式

方式一：合并所有插件资源

需要解决资源id冲突问题

资源ID值一共4个字段，由三部分组成：PackageId+TypeId+EntryId

• PackageId：是包的Id值，Android 中如果第三方应用的话，这个默认值是 0x7f，系统应用的话就是 0x01 ，插件的话那么就是给插件分配的id值，占用1个字节。
• TypeId：是资源的类型Id值，一般 Android 中有这几个类型：attr，drawable，layout，anim，raw，dimen，string，bool，style，integer，array，color，id，menu 等。【应用程序所有模块中的资源类型名称，按照字母排序之后。值是从1开支逐渐递增的，而且顺序不能改变（每个模块下的R文件的相同资源类型id值相同)。比如：anim=0x01占用1个字节，那么在这个编译出的所有R文件中anim 的值都是 0x01】
• EntryId:是在具体的类型下资源实例的id值，从0开始，依次递增，他占用2个字节。

两种解决方式

1. gradle3.5以上可以动态配置aapt的package-id参数修改插件apk的packageId，可在插件模块的build.gradle配置如下：

android {compileSdkVersion 32defaultConfig {applicationId "xxx"minSdkVersion 21targetSdkVersion 32versionCode 1versionName "1.0"}buildTypes {release {minifyEnabled falseproguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'}}compileOptions {sourceCompatibility JavaVersion.VERSION_1_8targetCompatibility JavaVersion.VERSION_1_8}//为模块定一个唯一的package-id，如0x80aaptOptions {additionalParameters '--allow-reserved-package-id','--package-id', '0x80'}
}

2. gradle3.5以下，可以将打包出来的插件apk包进行解包，修改public.xml文件内资源id的package-id，再扫描每一个R$xxx.smali文件，纠正代码中R类的值，与public.xml中的对应，重新打包。

反射替换Application中的mResources字段

注意：在启动service和receiver的时候，会使用application的resource

fun mergePatchResources(application: Application, apkPaths : List<String>) {val newAssetManagerObj = AssetManager::class.java.newInstance()//todo 需要注意这里的addAssetPath被标志为废弃了val addAssetPath = AssetManager::class.java.getMethod("addAssetPath", String::class.java)// 插入宿主的资源addAssetPath.invoke(newAssetManagerObj, application.baseContext.packageResourcePath)// 插入插件的资源apkPaths.forEach {addAssetPath.invoke(newAssetManagerObj, it)}val newResourcesObj = Resources(newAssetManagerObj,application.baseContext.resources.displayMetrics,application.baseContext.resources.configuration)newHoldResources = newResourcesObjval resourcesField = application.baseContext.javaClass.getDeclaredField("mResources")resourcesField.isAccessible = trueresourcesField[application.baseContext] = newResourcesObjval packageInfoField = application.baseContext.javaClass.getDeclaredField("mPackageInfo")packageInfoField.isAccessible = trueval packageInfoObj = packageInfoField[application.baseContext]// 获取 mPackageInfo 变量对象中类的Resources类型的mResources 变量，并替换它的值为新的Resources对象// 注意：这是最主要的需要替换的，如果不需要支持插件运行时更新，只留这一个就可以了val resourcesField2 = packageInfoObj.javaClass.getDeclaredField("mResources")resourcesField2.isAccessible = trueresourcesField2[packageInfoObj] = newResourcesObj// 获取 ContextImpl 中的 Resources.Theme 类型的 mTheme 变量，并至空它// 注意：清理mTheme对象，否则通过inflate方式加载资源会报错, 如果是activity动态加载插件，则需要把activity的mTheme对象也设置为nullval themeField = application.baseContext.javaClass.getDeclaredField("mTheme")themeField.isAccessible = truethemeField[application.baseContext] = null
}

更新Activity的资源

1. 监听activity的onCreate回调

((Application)context).registerActivityLifecycleCallbacks(new Application.ActivityLifecycleCallbacks() {@Overridepublic void onActivityCreated(@NonNull Activity activity, @Nullable Bundle savedInstanceState) {Log.d("zbm111", "doMonitorActivity---onCreate");Resources resources = "含宿主和所有插件资源的完整resource对象"ResHookUtil.monkeyPatchExistingResources(activity, resources);}@Overridepublic void onActivityStarted(@NonNull Activity activity) {}@Overridepublic void onActivityResumed(@NonNull Activity activity) {}@Overridepublic void onActivityPaused(@NonNull Activity activity) {}@Overridepublic void onActivityStopped(@NonNull Activity activity) {}@Overridepublic void onActivitySaveInstanceState(@NonNull Activity activity, @NonNull Bundle outState) {}@Overridepublic void onActivityDestroyed(@NonNull Activity activity) {}});

2. 将要启动的activity反射替换mResources字段

public static void monkeyPatchExistingResources(Activity activity, Resources newResources) {try {Class<?> contextThemeWrapperClass = null;try {contextThemeWrapperClass = Class.forName("android.view.ContextThemeWrapper");} catch (ClassNotFoundException e) {e.printStackTrace();}// 反射获取 ContextThemeWrapper 类的 mResources 字段Field mResourcesField = null;try {mResourcesField = contextThemeWrapperClass.getDeclaredField("mResources");} catch (NoSuchFieldException e) {e.printStackTrace();}// 设置字段可见性mResourcesField.setAccessible(true);// 将插件资源设置到插件 Activity 中try {mResourcesField.set(activity, newResources);} catch (IllegalAccessException e) {e.printStackTrace();}Method mTheme = contextThemeWrapperClass.getDeclaredMethod("setTheme", Resources.Theme.class);mTheme.setAccessible(true);mTheme.invoke(activity, (Object) null);} catch (Exception e) {e.printStackTrace();}}

方式二：封装含插件资源的Resource对象

注意：插件apk的包名须与宿主的包名保持一致

需要解决资源id冲突问题

参考方式一，可以通过修改type id与宿主区分开

hook ActivityThread的handler设置callback

1. 给ActivityThread中mH（Hander类型）对象的mCallback字段设置一个代理对象ProxyHandlerCallback

    public static void doHandlerHook(Context context) {try {HookUtils.context = context;Class<?> activityThreadClass = Class.forName("android.app.ActivityThread");Method currentActivityThread = activityThreadClass.getDeclaredMethod("currentActivityThread");Object activityThread = currentActivityThread.invoke(null);Field mHField = activityThreadClass.getDeclaredField("mH");mHField.setAccessible(true);Handler mH = (Handler) mHField.get(activityThread);Field mCallbackField = Handler.class.getDeclaredField("mCallback");mCallbackField.setAccessible(true);mCallbackField.set(mH, new ProxyHandlerCallback(mH));} catch (Exception e) {e.printStackTrace();}}

2. 系统启动service前，进行拦截，将ActivityThread的mPackages新增一个service的LoadedApk，该LoadedApk的mResources字段替换为含插件+宿主资源的SingleMixRes对象；
   系统启动receiver前，进行拦截，将application的mResources字段替换为含插件+宿主资源的SingleMixRes对象。

public class ProxyHandlerCallback implements Handler.Callback {private Handler mBaseHandler;private Map<String, String> mPathToPluginNameMap = new HashMap<>();public ProxyHandlerCallback(Handler mBaseHandler) {this.mBaseHandler = mBaseHandler;}@Overridepublic boolean handleMessage(Message msg) {Log.d("zbm111", "接受到消息了msg:" + msg);if (msg.what == 113){//启动receiver的时候走这里try {Object object = msg.obj;Field infoField = object.getClass().getDeclaredField("info");infoField.setAccessible(true);ActivityInfo activityInfo = (ActivityInfo) infoField.get(object);String hostReceiverName = activityInfo.name;Resources resources = "含插件+宿主资源的SingleMixRes对象";Field resourcesField = ((Application)HookUtils.getContext()).getBaseContext().getClass().getDeclaredField("mResources");resourcesField.setAccessible(true);resourcesField.set(((Application)HookUtils.getContext()).getBaseContext(), resources);}catch (Exception e){Log.e("zbm111", "handle create receiver failed");}} else if (msg.what == 114) {//启动service的时候走这里try {Object object = msg.obj;Field infoField = object.getClass().getDeclaredField("info");infoField.setAccessible(true);ServiceInfo serviceInfo = (ServiceInfo) infoField.get(object);String hostServiceName = serviceInfo.name;String path = "插件apk本地存储路径"//todo dex热修复必须同时进行资源热更if (path != null) {replaceLoadApk(hostServiceName, path, false);Log.i("zbm111", "replaced to plugin service success");}} catch (Exception e) {Log.e("zbm111", "handle create service failed");}}mBaseHandler.handleMessage(msg);return true;}private void replaceLoadApk(String componentName, String path, boolean isUseActivity) throws Exception {Log.i("zbm111", "start replaceLoadApk");Field activityThreadField = Class.forName("android.app.ActivityThread").getDeclaredField("sCurrentActivityThread");activityThreadField.setAccessible(true);Object sCurrentActivityThread = activityThreadField.get(null);Field mPackagesField = sCurrentActivityThread.getClass().getDeclaredField("mPackages");mPackagesField.setAccessible(true);ArrayMap mPackages = (ArrayMap) mPackagesField.get(sCurrentActivityThread);if (null == mPackages) {Log.i("zbm111", "can not get mPackages");return;}ApplicationInfo applicationInfo = generateApplicationInfo(path);if (null != applicationInfo) {Field compatibilityInfoField = Class.forName("android.content.res.CompatibilityInfo").getDeclaredField("DEFAULT_COMPATIBILITY_INFO");compatibilityInfoField.setAccessible(true);Object defaultCompatibilityInfo = compatibilityInfoField.get(null);Object loadedApk;if (isUseActivity){Method getPackageInfoMethod = sCurrentActivityThread.getClass().getDeclaredMethod("getPackageInfo", ApplicationInfo.class, Class.forName("android.content.res.CompatibilityInfo"), int.class);getPackageInfoMethod.setAccessible(true);loadedApk = getPackageInfoMethod.invoke(sCurrentActivityThread, applicationInfo, defaultCompatibilityInfo, Context.CONTEXT_INCLUDE_CODE);}else {Method getPackageInfoMethod = sCurrentActivityThread.getClass().getDeclaredMethod("getPackageInfoNoCheck", ApplicationInfo.class, Class.forName("android.content.res.CompatibilityInfo"));getPackageInfoMethod.setAccessible(true);loadedApk = getPackageInfoMethod.invoke(sCurrentActivityThread, applicationInfo, defaultCompatibilityInfo);}String pluginName = applicationInfo.packageName;if (!TextUtils.isEmpty(pluginName)) {Log.i("zbm111", "plugin pkg name is " + pluginName);Resources resources = "含插件+宿主资源的SingleMixRes对象";setResource(loadedApk, resources);mPackages.put(pluginName, new WeakReference<>(loadedApk));mPackagesField.set(sCurrentActivityThread, mPackages);mPathToPluginNameMap.put(path, pluginName);} else {Log.i("zbm111", "get plugin pkg name failed");}} else {Log.i("zbm111", "can not get application info");}}private void setResource(Object loadedApk, Resources resources) throws Exception{Field mResourcesField = loadedApk.getClass().getDeclaredField("mResources");mResourcesField.setAccessible(true);mResourcesField.set(loadedApk, resources);}public ApplicationInfo generateApplicationInfo(String pluginPath) {try {ApplicationInfo applicationInfo = getApplicationInfoByPackageArchiveInfo(pluginPath);if (null == applicationInfo) {LogUtil.i("zbm111", "get applicationInfo failed");return null;}applicationInfo.sourceDir = pluginPath;applicationInfo.publicSourceDir = pluginPath;return applicationInfo;} catch (Exception e) {LogUtil.i("zbm111", "generateApplicationzInfo failed " + e.getMessage());}return null;}private ApplicationInfo getApplicationInfoByPackageArchiveInfo(String pluginPath) {PackageManager packageManager = HookUtils.getContext().getPackageManager();if (null == packageManager) {LogUtil.i("zbm111", "get PackageManager failed");return null;}PackageInfo packageInfo = packageManager.getPackageArchiveInfo(pluginPath, 0);if (null == packageInfo) {LogUtil.i("zbm111", "get packageInfo failed");return null;}return packageInfo.applicationInfo;}
}

3. 自定义ResourcesWrapper

public class ResourcesWrapper extends Resources {private Resources mBase;public ResourcesWrapper(Resources base){super(base.getAssets(),base.getDisplayMetrics(),base.getConfiguration());mBase = base;}@Overridepublic CharSequence getText(int id) throws NotFoundException {return mBase.getText(id);}@TargetApi(Build.VERSION_CODES.O)@Overridepublic Typeface getFont(int id) throws NotFoundException {return mBase.getFont(id);}@Overridepublic CharSequence getQuantityText(int id, int quantity) throws NotFoundException {return mBase.getQuantityText(id, quantity);}@Overridepublic String getString(int id) throws NotFoundException {return mBase.getString(id);}@Overridepublic String getString(int id, Object... formatArgs) throws NotFoundException {return mBase.getString(id, formatArgs);}@Overridepublic String getQuantityString(int id, int quantity, Object... formatArgs) throws NotFoundException {return mBase.getQuantityString(id, quantity, formatArgs);}@Overridepublic String getQuantityString(int id, int quantity) throws NotFoundException {return mBase.getQuantityString(id, quantity);}@Overridepublic CharSequence getText(int id, CharSequence def) {return mBase.getText(id, def);}@Overridepublic CharSequence[] getTextArray(int id) throws NotFoundException {return mBase.getTextArray(id);}@Overridepublic String[] getStringArray(int id) throws NotFoundException {return mBase.getStringArray(id);}@Overridepublic int[] getIntArray(int id) throws NotFoundException {return mBase.getIntArray(id);}@Overridepublic TypedArray obtainTypedArray(int id) throws NotFoundException {return mBase.obtainTypedArray(id);}@Overridepublic float getDimension(int id) throws NotFoundException {return mBase.getDimension(id);}@Overridepublic int getDimensionPixelOffset(int id) throws NotFoundException {return mBase.getDimensionPixelOffset(id);}@Overridepublic int getDimensionPixelSize(int id) throws NotFoundException {return mBase.getDimensionPixelSize(id);}@Overridepublic float getFraction(int id, int base, int pbase) {return mBase.getFraction(id, base, pbase);}@Overridepublic Drawable getDrawable(int id) throws NotFoundException {return mBase.getDrawable(id);}@TargetApi(Build.VERSION_CODES.LOLLIPOP)@Overridepublic Drawable getDrawable(int id, Theme theme) throws NotFoundException {return mBase.getDrawable(id, theme);}@Overridepublic Drawable getDrawableForDensity(int id, int density) throws NotFoundException {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH_MR1) {return mBase.getDrawableForDensity(id, density);} else {return null;}}@TargetApi(Build.VERSION_CODES.LOLLIPOP)@Overridepublic Drawable getDrawableForDensity(int id, int density, Theme theme) {return mBase.getDrawableForDensity(id, density, theme);}@Overridepublic Movie getMovie(int id) throws NotFoundException {return mBase.getMovie(id);}@Overridepublic int getColor(int id) throws NotFoundException {return mBase.getColor(id);}@TargetApi(Build.VERSION_CODES.M)@Overridepublic int getColor(int id, Theme theme) throws NotFoundException {return mBase.getColor(id, theme);}@Overridepublic ColorStateList getColorStateList(int id) throws NotFoundException {return mBase.getColorStateList(id);}@TargetApi(Build.VERSION_CODES.M)@Overridepublic ColorStateList getColorStateList(int id, Theme theme) throws NotFoundException {return mBase.getColorStateList(id, theme);}@Overridepublic boolean getBoolean(int id) throws NotFoundException {return mBase.getBoolean(id);}@Overridepublic int getInteger(int id) throws NotFoundException {return mBase.getInteger(id);}@Overridepublic XmlResourceParser getLayout(int id) throws NotFoundException {return mBase.getLayout(id);}@Overridepublic XmlResourceParser getAnimation(int id) throws NotFoundException {return mBase.getAnimation(id);}@Overridepublic XmlResourceParser getXml(int id) throws NotFoundException {return mBase.getXml(id);}@Overridepublic InputStream openRawResource(int id) throws NotFoundException {return mBase.openRawResource(id);}@Overridepublic InputStream openRawResource(int id, TypedValue value) throws NotFoundException {return mBase.openRawResource(id, value);}@Overridepublic AssetFileDescriptor openRawResourceFd(int id) throws NotFoundException {return mBase.openRawResourceFd(id);}@Overridepublic void getValue(int id, TypedValue outValue, boolean resolveRefs) throws NotFoundException {mBase.getValue(id, outValue, resolveRefs);}@Overridepublic void getValueForDensity(int id, int density, TypedValue outValue, boolean resolveRefs) throws NotFoundException {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH_MR1) {mBase.getValueForDensity(id, density, outValue, resolveRefs);}}@Overridepublic void getValue(String name, TypedValue outValue, boolean resolveRefs) throws NotFoundException {mBase.getValue(name, outValue, resolveRefs);}@Overridepublic TypedArray obtainAttributes(AttributeSet set, int[] attrs) {return mBase.obtainAttributes(set, attrs);}@Overridepublic DisplayMetrics getDisplayMetrics() {return mBase.getDisplayMetrics();}@Overridepublic Configuration getConfiguration() {return mBase.getConfiguration();}@Overridepublic int getIdentifier(String name, String defType, String defPackage) {return mBase.getIdentifier(name, defType, defPackage);}@Overridepublic String getResourceName(int resid) throws NotFoundException {return mBase.getResourceName(resid);}@Overridepublic String getResourcePackageName(int resid) throws NotFoundException {return mBase.getResourcePackageName(resid);}@Overridepublic String getResourceTypeName(int resid) throws NotFoundException {return mBase.getResourceTypeName(resid);}@Overridepublic String getResourceEntryName(int resid) throws NotFoundException {return mBase.getResourceEntryName(resid);}@Overridepublic void parseBundleExtras(XmlResourceParser parser, Bundle outBundle) throws XmlPullParserException, IOException {mBase.parseBundleExtras(parser, outBundle);}@Overridepublic void parseBundleExtra(String tagName, AttributeSet attrs, Bundle outBundle) throws XmlPullParserException {mBase.parseBundleExtra(tagName, attrs, outBundle);}
}

4. SingleMixRes优先从插件加载资源，找不到则从宿主加载资源

public class SingleMixRes extends ResourcesWrapper{private Resources mHostResources;public SingleMixRes(Resources hostResources, Resources pluginResources) {super(pluginResources);mHostResources = hostResources;}@Overridepublic CharSequence getText(int id) throws NotFoundException {try {return super.getText(id);} catch (NotFoundException e) {return mHostResources.getText(id);}}@Overridepublic String getString(int id) throws NotFoundException {try {return super.getString(id);} catch (NotFoundException e) {return mHostResources.getString(id);}}@Overridepublic String getString(int id, Object... formatArgs) throws NotFoundException {try {return super.getString(id,formatArgs);} catch (NotFoundException e) {return mHostResources.getString(id,formatArgs);}}@Overridepublic float getDimension(int id) throws NotFoundException {try {return super.getDimension(id);} catch (NotFoundException e) {return mHostResources.getDimension(id);}}@Overridepublic int getDimensionPixelOffset(int id) throws NotFoundException {try {return super.getDimensionPixelOffset(id);} catch (NotFoundException e) {return mHostResources.getDimensionPixelOffset(id);}}@Overridepublic int getDimensionPixelSize(int id) throws NotFoundException {try {return super.getDimensionPixelSize(id);} catch (NotFoundException e) {return mHostResources.getDimensionPixelSize(id);}}@Overridepublic Drawable getDrawable(int id) throws NotFoundException {try {return super.getDrawable(id);} catch (NotFoundException e) {return mHostResources.getDrawable(id);}}@TargetApi(Build.VERSION_CODES.LOLLIPOP)@Overridepublic Drawable getDrawable(int id, Theme theme) throws NotFoundException {try {return super.getDrawable(id, theme);} catch (NotFoundException e) {return mHostResources.getDrawable(id,theme);}}@Overridepublic Drawable getDrawableForDensity(int id, int density) throws NotFoundException {try {return super.getDrawableForDensity(id, density);} catch (NotFoundException e) {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH_MR1) {return mHostResources.getDrawableForDensity(id, density);} else {return null;}}}@TargetApi(Build.VERSION_CODES.LOLLIPOP)@Overridepublic Drawable getDrawableForDensity(int id, int density, Theme theme) {try {return super.getDrawableForDensity(id, density, theme);} catch (Exception e) {return mHostResources.getDrawableForDensity(id,density,theme);}}@Overridepublic int getColor(int id) throws NotFoundException {try {return super.getColor(id);} catch (NotFoundException e) {return mHostResources.getColor(id);}}@TargetApi(Build.VERSION_CODES.M)@Overridepublic int getColor(int id, Theme theme) throws NotFoundException {try {return super.getColor(id,theme);} catch (NotFoundException e) {return mHostResources.getColor(id,theme);}}@Overridepublic ColorStateList getColorStateList(int id) throws NotFoundException {try {return super.getColorStateList(id);} catch (NotFoundException e) {return mHostResources.getColorStateList(id);}}@TargetApi(Build.VERSION_CODES.M)@Overridepublic ColorStateList getColorStateList(int id, Theme theme) throws NotFoundException {try {return super.getColorStateList(id,theme);} catch (NotFoundException e) {return mHostResources.getColorStateList(id,theme);}}@Overridepublic boolean getBoolean(int id) throws NotFoundException {try {return super.getBoolean(id);} catch (NotFoundException e) {return mHostResources.getBoolean(id);}}@Overridepublic XmlResourceParser getLayout(int id) throws NotFoundException {try {return super.getLayout(id);} catch (NotFoundException e) {return mHostResources.getLayout(id);}}@Overridepublic String getResourceName(int resid) throws NotFoundException {try {return super.getResourceName(resid);} catch (NotFoundException e) {return mHostResources.getResourceName(resid);}}@Overridepublic int getInteger(int id) throws NotFoundException {try {return super.getInteger(id);} catch (NotFoundException e) {return mHostResources.getInteger(id);}}@Overridepublic CharSequence getText(int id, CharSequence def) {try {return super.getText(id,def);} catch (NotFoundException e) {return mHostResources.getText(id,def);}}@Overridepublic InputStream openRawResource(int id) throws NotFoundException {try {return super.openRawResource(id);} catch (NotFoundException e) {return mHostResources.openRawResource(id);}}@Overridepublic XmlResourceParser getXml(int id) throws NotFoundException {try {return super.getXml(id);} catch (NotFoundException e) {return mHostResources.getXml(id);}}@TargetApi(Build.VERSION_CODES.O)@Overridepublic Typeface getFont(int id) throws NotFoundException {try {return super.getFont(id);} catch (NotFoundException e) {return mHostResources.getFont(id);}}@Overridepublic Movie getMovie(int id) throws NotFoundException {try {return super.getMovie(id);} catch (NotFoundException e) {return mHostResources.getMovie(id);}}@Overridepublic XmlResourceParser getAnimation(int id) throws NotFoundException {try {return super.getAnimation(id);} catch (NotFoundException e) {return mHostResources.getAnimation(id);}}@Overridepublic InputStream openRawResource(int id, TypedValue value) throws NotFoundException {try {return super.openRawResource(id,value);} catch (NotFoundException e) {return mHostResources.openRawResource(id,value);}}@Overridepublic AssetFileDescriptor openRawResourceFd(int id) throws NotFoundException {try {return super.openRawResourceFd(id);} catch (NotFoundException e) {return mHostResources.openRawResourceFd(id);}}
}

更新Activity的资源

参考方式一

两种方式注意事项

1. 打包出的插件apk需要去除第三方smali代码，否则可能会报资源问题
2. 代码更新与资源更新最好同步，预防id对应不上

附录

修改资源id冲突及去除第三方smali文件工具