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Android 6.0与9.0 加载WebView Resource 的区别

程序员文章站 2022-06-04 15:07:01
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从前两篇文章里面我们分析了 6.0的资源管理机制和9.0的资源管理机制

先说以下6.0的 

根据6.0 ResourceManager的代码 我们先做一个测试

编写如下代码 我们将mActiveResources中保存的内容打印出来

                ResourcesManager resourcesManager = ResourcesManager.getInstance();
                //6.0打印
                try {
                    ArrayMap<Object, WeakReference<Object>> map = Reflector.with(resourcesManager).field("mActiveResources").get();
                    for (int i = 0; i < map.size(); i++) {
                        Object a = map.keyAt(i);
                        Object b = map.valueAt(i).get();
                        System.out.println(Reflector.with(a).field("mResDir").get());
                        System.out.println(b.toString());
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }

打印输出

10-12 15:47:02.816 10785-10785/com.vivo.res_manager_study I/System.out: /data/app/com.vivo.res_manager_study-1/base.apk
10-12 15:47:02.816 10785-10785/com.vivo.res_manager_study I/System.out: [email protected]

可以看到当前包的Resources已经被加入到mActiveResources中了

再修改代码

在打印之前添加webView初始化

WebView webView = new WebView(context);

打印输出

10-12 15:48:48.586 10985-10985/com.vivo.res_manager_study I/System.out: /data/app/com.google.android.webview-1/base.apk
10-12 15:48:48.586 10985-10985/com.vivo.res_manager_study I/System.out: [email protected]
10-12 15:48:48.586 10985-10985/com.vivo.res_manager_study I/System.out: /data/app/com.vivo.res_manager_study-2/base.apk
10-12 15:48:48.586 10985-10985/com.vivo.res_manager_study I/System.out: [email protected]

可以看到添加了webView初始化代码之后 mActiveResources中增加了一个Resources实例，该实例指向webView组件安装路径

WebView就是从这个Resources取到了自己所需要的资源

这也是7.0以下版本中替换Activity和Application的Resources不会出现Web组件崩溃的原因，因为在这个level的系统中，web组件资源与主apk资源是分离的

 

OK 分析完6.0的再看9.0的

9.0的ResourceManager相对复杂 我们也是使用反射的方法将两种情况下的ResourceManager数据打印出来

编写打印代码

                System.out.println(" 打印 mResourceImpls 中缓存的 ResourceImpl");
                ResourcesManager resourcesManager = ResourcesManager.getInstance();
                // 9.0源码
                try {
                    ArrayMap map = Reflector.with(resourcesManager).field("mResourceImpls").get();
                    for (int i = 0; i < map.size(); i++) {
                        Object key = map.keyAt(i);
                        WeakReference value = (WeakReference) map.get(key);
                        System.out.println(value.get() + "  " + key);
                    }
                } catch (Reflector.ReflectedException e) {
                    e.printStackTrace();
                }
                System.out.println(" 打印 mActivityResourceReferences 中缓存的 Activity Resources");
                try {
                    WeakHashMap<Object, Object> map = Reflector.with(resourcesManager).field("mActivityResourceReferences").get();
                    for (Map.Entry<Object, Object> entry : map.entrySet()) {
                        Object activityResources = entry.getValue();
                        ArrayList<WeakReference<Resources>> list = Reflector.with(activityResources).field("activityResources").get();
                        for (WeakReference<Resources> weakReference : list) {
                            Resources resources = weakReference.get();
                            Object resourcesImpl = Reflector.with(resources).field("mResourcesImpl").get();
                            System.out.println(resourcesImpl);
                        }
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }

在这份打印代码中 我们输出了mResourceImpls和mActivityResourceReferences中的数据 不理解这两个缓存作用的可以去看之前的文章

打印输出

I/System.out:  打印 mResourceImpls 中缓存的 ResourceImpl
I/System.out: [email protected]  ResourcesKey{ mHash=8a5fac6a mResDir=null mSplitDirs=[] mOverlayDirs=[] mLibDirs=[] mDisplayId=0 mOverrideConfig=v28 mCompatInfo={480dpi always-compat}}
I/System.out: [email protected]  ResourcesKey{ mHash=bafccb1 mResDir=/data/app/com.vivo.res_manager_study-_k1QRBE8jUyrPTVnJDIbsA==/base.apk mSplitDirs=[] mOverlayDirs=[] mLibDirs=[/system/framework/org.apache.http.legacy.boot.jar] mDisplayId=0 mOverrideConfig=v28 mCompatInfo={480dpi always-compat}}
I/System.out: [email protected]  ResourcesKey{ mHash=30333beb mResDir=/data/app/com.vivo.res_manager_study-_k1QRBE8jUyrPTVnJDIbsA==/base.apk mSplitDirs=[] mOverlayDirs=[] mLibDirs=[/system/framework/org.apache.http.legacy.boot.jar] mDisplayId=0 mOverrideConfig=en-rUS-ldltr-sw360dp-w360dp-h752dp-normal-long-notround-lowdr-nowidecg-port-notnight-xxhdpi-finger-keysexposed-nokeys-navhidden-nonav-v28 mCompatInfo={480dpi always-compat}}
I/System.out:  打印 mActivityResourceReferences 中缓存的 Activity Resources
I/System.out: [email protected]

根据 mActivityResourceReferences中AcitvityResource 我们找到对应的ResourcesImpl并且根据ResourceKey得知了ResourcesImpl中的内容

mResDir=/data/app/com.vivo.res_manager_study-_k1QRBE8jUyrPTVnJDIbsA==/base.apk 
mSplitDirs=[] 
mOverlayDirs=[] 
mLibDirs=[/system/framework/org.apache.http.legacy.boot.jar] 
mDisplayId=0 
mOverrideConfig=en-rUS-ldltr-sw360dp-w360dp-h752dp-normal-long-notround-lowdr-nowidecg-port-notnight-xxhdpi-finger-keysexposed-nokeys-navhidden-nonav-v28 mCompatInfo={480dpi always-compat}}

下面我们在打印代码之前添加初始化webView的源码

                new WebView(MainActivity.this);
                System.out.println(" 打印 mResourceImpls 中缓存的 ResourceImpl");
                ResourcesManager resourcesManager = ResourcesManager.getInstance();
                // 9.0源码
                try {
                    ArrayMap map = Reflector.with(resourcesManager).field("mResourceImpls").get();
                    for (int i = 0; i < map.size(); i++) {
                        Object key = map.keyAt(i);
                        WeakReference value = (WeakReference) map.get(key);
                        System.out.println(value.get() + "  " + key);
                    }
                } catch (Reflector.ReflectedException e) {
                    e.printStackTrace();
                }
                System.out.println(" 打印 mActivityResourceReferences 中缓存的 Activity Resources");
                try {
                    WeakHashMap<Object, Object> map = Reflector.with(resourcesManager).field("mActivityResourceReferences").get();
                    for (Map.Entry<Object, Object> entry : map.entrySet()) {
                        Object activityResources = entry.getValue();
                        ArrayList<WeakReference<Resources>> list = Reflector.with(activityResources).field("activityResources").get();
                        for (WeakReference<Resources> weakReference : list) {
                            Resources resources = weakReference.get();
                            Object resourcesImpl = Reflector.with(resources).field("mResourcesImpl").get();
                            System.out.println(resourcesImpl);
                        }
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }

打印输出

I/System.out:  打印 mResourceImpls 中缓存的 ResourceImpl
I/System.out: [email protected]  ResourcesKey{ mHash=8a5fac6a mResDir=null mSplitDirs=[] mOverlayDirs=[] mLibDirs=[] mDisplayId=0 mOverrideConfig=v28 mCompatInfo={480dpi always-compat}}
I/System.out: [email protected]  ResourcesKey{ mHash=25ddf2aa mResDir=/data/app/com.vivo.res_manager_study-sVY46cDW2JT2hEkohn2GJw==/base.apk mSplitDirs=[] mOverlayDirs=[] mLibDirs=[/system/framework/org.apache.http.legacy.boot.jar,/data/app/com.android.chrome-dO2jAeCdfgkLjVHzK2yx0Q==/base.apk] mDisplayId=0 mOverrideConfig=v28 mCompatInfo={480dpi always-compat}}
I/System.out: [email protected]  ResourcesKey{ mHash=4114b0be mResDir=/data/app/com.android.chrome-dO2jAeCdfgkLjVHzK2yx0Q==/base.apk mSplitDirs=[/data/app/com.android.chrome-dO2jAeCdfgkLjVHzK2yx0Q==/split_autofill_assistant.apk,/data/app/com.android.chrome-dO2jAeCdfgkLjVHzK2yx0Q==/split_autofill_assistant.config.en.apk,/data/app/com.android.chrome-dO2jAeCdfgkLjVHzK2yx0Q==/split_autofill_assistant.config.in.apk,/data/app/com.android.chrome-dO2jAeCdfgkLjVHzK2yx0Q==/split_autofill_assistant.config.ms.apk,/data/app/com.android.chrome-dO2jAeCdfgkLjVHzK2yx0Q==/split_autofill_assistant.config.zh.apk,/data/app/com.android.chrome-dO2jAeCdfgkLjVHzK2yx0Q==/split_config.en.apk,/data/app/com.android.chrome-dO2jAeCdfgkLjVHzK2yx0Q==/split_config.in.apk,/data/app/com.android.chrome-dO2jAeCdfgkLjVHzK2yx0Q==/split_config.ms.apk,/data/app/com.android.chrome-dO2jAeCdfgkLjVHzK2yx0Q==/split_config.zh.apk] mOverlayDirs=[] mLibDirs=[] mDisplayId=0 mOverrideConfig=v28 mCompatInfo={480dpi always-compat}}
I/System.out: [email protected]  ResourcesKey{ mHash=4a6161e4 mResDir=/data/app/com.vivo.res_manager_study-sVY46cDW2JT2hEkohn2GJw==/base.apk mSplitDirs=[] mOverlayDirs=[] mLibDirs=[/system/framework/org.apache.http.legacy.boot.jar,/data/app/com.android.chrome-dO2jAeCdfgkLjVHzK2yx0Q==/base.apk] mDisplayId=0 mOverrideConfig=en-rUS-ldltr-sw360dp-w360dp-h752dp-normal-long-notround-lowdr-nowidecg-port-notnight-xxhdpi-finger-keysexposed-nokeys-navhidden-nonav-v28 mCompatInfo={480dpi always-compat}}
I/System.out: [email protected]  ResourcesKey{ mHash=578cb784 mResDir=/data/app/com.vivo.res_manager_study-sVY46cDW2JT2hEkohn2GJw==/base.apk mSplitDirs=[] mOverlayDirs=[] mLibDirs=[/system/framework/org.apache.http.legacy.boot.jar] mDisplayId=0 mOverrideConfig=v28 mCompatInfo={480dpi always-compat}}
I/System.out: [email protected]  ResourcesKey{ mHash=7c1026be mResDir=/data/app/com.vivo.res_manager_study-sVY46cDW2JT2hEkohn2GJw==/base.apk mSplitDirs=[] mOverlayDirs=[] mLibDirs=[/system/framework/org.apache.http.legacy.boot.jar] mDisplayId=0 mOverrideConfig=en-rUS-ldltr-sw360dp-w360dp-h752dp-normal-long-notround-lowdr-nowidecg-port-notnight-xxhdpi-finger-keysexposed-nokeys-navhidden-nonav-v28 mCompatInfo={480dpi always-compat}}
I/System.out:  打印 mActivityResourceReferences 中缓存的 Activity Resources
I/System.out: [email protected]

同样 根据 mActivityResourceReferences中AcitvityResource 我们找到对应的ResourcesImpl并且根据ResourceKey得知了ResourcesImpl中的内容

mResDir=/data/app/com.vivo.res_manager_study-sVY46cDW2JT2hEkohn2GJw==/base.apk mSplitDirs=[]
mOverlayDirs=[] 
mLibDirs=[/system/framework/org.apache.http.legacy.boot.jar,
/data/app/com.android.chrome-dO2jAeCdfgkLjVHzK2yx0Q==/base.apk] 
mDisplayId=0 
mOverrideConfig=en-rUS-ldltr-sw360dp-w360dp-h752dp-normal-long-notround-lowdr-nowidecg-port-notnight-xxhdpi-finger-keysexposed-nokeys-navhidden-nonav-v28 
mCompatInfo={480dpi always-compat}

对比没有添加webview 实例化之前的代码 我们发现mLibDirs中新增了

/data/app/com.android.chrome-dO2jAeCdfgkLjVHzK2yx0Q==/base.apk

从7.0开始 android将Web组件资源作为libDir添加至Assert中，用于资源查找，没有完全使用Resource分离的方式

 

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