Android 应用间资源覆盖
2020-01-19 本文已影响0人
古风子
该方案基于android 9.x验证
问题描述
客户想要我们的主应用MainApp，但是想通过值改变资源应用ResApp，达到改变应用多语言翻译的需求
也就是，我们提供给客户MainApp的apk文件，和ResApp的源码文件，客户通过改变ResApp，来控制MainApp的显示。
解决方案 1
- 将两个apk shared到同一个进程中去
//主应用 MainApp
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.jdf.res.main"
android:sharedUserId="com.jdf.res">
//资源应用 ResApp
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.jdf.res.resapp"
android:sharedUserId="com.jdf.res">
- 将两个应用新增同样名称，不同值的资源字段
//主应用 MainApp-默认资源
<resources>
<string name="app_name">MainApp</string>
<string name="test1">Main App test1</string>
<string name="test2">Main App test2</string>
<string name="test3">Main App test3</string>
<string name="test4">Main App test4</string>
<string name="test5">Main App test5</string>
<string name="test6">Main App test6</string>
</resources>
//资源应用 ResApp--默认资源
<resources>
<string name="app_name">ResApp</string>
<string name="test1">Res app test1</string>
<string name="test2">Res app test2</string>
<string name="test3">Res app test3</string>
<string name="test4">Res app test4</string>
<string name="test5">Res app test5</string>
<string name="test6">Res app test6</string>
</resources>
//资源应用 ResApp--中文资源
<resources>
<string name="app_name">资源应用</string>
<string name="test1">资源应用 test1</string>
<string name="test2">资源应用 test2</string>
<string name="test3">资源应用 test3</string>
<string name="test4">资源应用 test4</string>
<string name="test5">资源应用 test5</string>
<string name="test6">资源应用 test6</string>
</resources>
- 然后在主应用，覆盖resource值为资源应用的resource
//主应用 MainApp
@Override
public Resources getResources() {
Context context = null;
try {
context = createPackageContext("com.jdf.res.resapp", Context.CONTEXT_IGNORE_SECURITY);
} catch (PackageManager.NameNotFoundException e) {
e.printStackTrace();
}
if (context != null) {
return context.getResources();
} else {
return super.getResources();
}
}
通过以上方式覆盖后，我们再访问资源时，访问的就是资源应用的
Log.d("res", "Main app res string:" + getString(R.string.test1));
Log.d("res", "Main app res string:" + getString(R.string.test2));
Log.d("res", "Main app res string:" + getString(R.string.test3));
Log.d("res", "Main app res string:" + getString(R.string.test4));
Log.d("res", "Main app res string:" + getString(R.string.test5));
Log.d("res", "Main app res string:" + getString(R.string.test6));
- 测试结果
2010-01-01 08:37:02.153 8481-8481/com.jdf.res.main D/res: Main app res string:资源应用 test1
2010-01-01 08:37:02.156 8481-8481/com.jdf.res.main D/res: Main app res string:资源应用 test2
2010-01-01 08:37:02.157 8481-8481/com.jdf.res.main D/res: Main app res string:资源应用 test3
2010-01-01 08:37:02.159 8481-8481/com.jdf.res.main D/res: Main app res string:资源应用 test4
2010-01-01 08:37:02.161 8481-8481/com.jdf.res.main D/res: Main app res string:资源应用 test5
2010-01-01 08:37:02.162 8481-8481/com.jdf.res.main D/res: Main app res string:资源应用 test6
为什么能够访问到资源应用的字符串
原因是通过 android:sharedUserId将两个应用share到同一个进程，两个apk的同一个资源属性的资源id是相同的；然后通过覆盖resource，就能够通过资源id，访问到到另外一个应用的资源了
通过反编译，我们看下，两个应用的，新增的字符串属性的资源id编号
//主应用的资源id
/* renamed from: com.jdf.res.main.R$string */
public static final class string {
public static final int test1 = 2131492894;
public static final int test2 = 2131492895;
public static final int test3 = 2131492896;
public static final int test4 = 2131492897;
public static final int test5 = 2131492898;
public static final int test6 = 2131492899;
}
//资源应用的资源id
/* renamed from: com.jdf.res.resapp.R$string */
public static final class string {
.....
public static final int test1 = 2131492894;
public static final int test2 = 2131492895;
public static final int test3 = 2131492896;
public static final int test4 = 2131492897;
public static final int test5 = 2131492898;
public static final int test6 = 2131492899;
}
这种方式，在xml引用资源，同样适用，因为资源文件，也是通过调用处的上下文ressource加载的。
有一个缺点，主应用MainApp的桌面app名称，还是应用自己的，而不是ResApp的。
下面我们针对其他应用获取应用方式，针对性的解决应用名称不能替换的问题
应用名称获取方式 1
public static String getApplicationNameByPackageName(Context context, String packageName) {
PackageManager pm = context.getPackageManager();
String Name;
try {
Name = pm.getApplicationLabel(pm.getApplicationInfo(packageName, PackageManager.GET_META_DATA)).toString();
} catch (PackageManager.NameNotFoundException e) {
Name = "";
}
return Name;
}
如上所示，桌面是通过获取各个应用的getApplicationLabel获取应用名称的，所以，如果达到MainApp显示的应用名称也是ResApp的，我们还需要修改系统代码，覆盖MainApp的名称
系统修改修改方法：
diff --git a/base/core/java/android/app/ApplicationPackageManager.java b/base/core/java/android/app/ApplicationPackageManager.java
index b1a5651..40db061
--- a/base/core/java/android/app/ApplicationPackageManager.java
+++ b/base/core/java/android/app/ApplicationPackageManager.java
@@ -1755,7 +1755,10 @@ public class ApplicationPackageManager extends PackageManager {
@Override
public CharSequence getApplicationLabel(ApplicationInfo info) {
- return info.loadLabel(this);
+
+ return LabelManager.replaceLabel(this, info);
+
+// return info.loadLabel(this);
}
应用名称获取方式2
//LauncherActivityInfo.getLabel
public CharSequence getLabel() {
// TODO: Go through LauncherAppsService
return mActivityInfo.loadLabel(mPm);
}
//PackageItemInfo
public @NonNull CharSequence loadLabel(@NonNull PackageManager pm) {
if (sForceSafeLabels) {
return loadSafeLabel(pm);//里面也会调用loadUnsafeLabel方法
} else {
return loadUnsafeLabel(pm);
}
}
/** {@hide} */
public CharSequence loadUnsafeLabel(PackageManager pm) {
if (nonLocalizedLabel != null) {
CharSequence replacedLabel = LabelManager.loadUnsafeLabel(pm, packageName, labelRes, getApplicationInfo());
return nonLocalizedLabel;
}
if (labelRes != 0) {
CharSequence label = pm.getText(packageName, labelRes, getApplicationInfo());
if (label != null) {
return label.toString().trim();
}
}
if (name != null) {
return name;
}
return packageName;
}
考虑到子类覆盖的情况
xxx@ubuntu:~/xxx/android/xxx/frameworks/base/core/java$ grep -nr "loadUnsafeLabel(PackageManager pm)"
android/content/pm/ComponentInfo.java:100: @Override public CharSequence loadUnsafeLabel(PackageManager pm) {
android/content/pm/PackageItemInfo.java:199: public CharSequence loadUnsafeLabel(PackageManager pm) {
需要对ComponentInfo.java和PackageItemInfo.java两个类的loadUnsafeLabel方法进行处理
//ComponentInfo.java
/** @hide */
@Override public CharSequence loadUnsafeLabel(PackageManager pm) {
if (nonLocalizedLabel != null) {
return nonLocalizedLabel;
}
ApplicationInfo ai = applicationInfo;
CharSequence label;
if (labelRes != 0) {
- label = pm.getText(packageName, labelRes, ai);
+ /* add for res replace */
+ label = LabelManager.loadUnsafeLabel(pm, packageName, labelRes, ai);
+ //label = pm.getText(packageName, labelRes, ai);
if (label != null) {
return label;
}
@@ -126,7 +130,10 @@ public class ComponentInfo extends PackageItemInfo {
return ai.nonLocalizedLabel;
}
if (ai.labelRes != 0) {
- label = pm.getText(packageName, ai.labelRes, ai);
+ /* add for res replace */
+ label = LabelManager.loadUnsafeLabel(pm, packageName, ai.labelRes, ai);
+ //label = pm.getText(packageName, ai.labelRes, ai);
if (label != null) {
return label;
}
//PackageItemInfo.java
/** {@hide} */
public CharSequence loadUnsafeLabel(PackageManager pm) {
if (nonLocalizedLabel != null) {
return nonLocalizedLabel;
}
if (labelRes != 0) {
- CharSequence label = pm.getText(packageName, labelRes, getApplicationInfo());
+ /* add for camera res replace */
+ CharSequence label = LabelManager.loadUnsafeLabel(pm, packageName, labelRes, getApplicationInfo());
+ //CharSequence label = pm.getText(packageName, labelRes, getApplicationInfo());
if (label != null) {
return label.toString().trim();
}
LabelManager的实现
package android.app;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;
import android.util.Log;
public class LabelManager {
public static final String TAG = "LabelManager";
public static final boolean IS_SUPPORT_LABEL_MAR = true;
private static final String[] REPLACE_FROM_PKGS = new String[] {
"com.jdf.res.main",
"com.android.camera"
};
private static final String[] REPLACE_TO_PKGS = new String[] {
"com.jdf.res.resapp",
"test.android.camera"
};
private static String getReplacedPkg(String pkg) {
if (pkg != null) {
for (int i = 0; i < REPLACE_FROM_PKGS.length; i++) {
if (pkg.equals(REPLACE_FROM_PKGS[i])) {
return REPLACE_TO_PKGS[i];
}
}
}
return null;
}
public static CharSequence replaceLabel(PackageManager pm, ApplicationInfo info) {
if (IS_SUPPORT_LABEL_MAR) {
final String replacedPkg = getReplacedPkg(info.packageName);
if (replacedPkg != null) {//属于label要被替代的应用
ApplicationInfo replacedInfo;
try {
replacedInfo = pm.getApplicationInfo(replacedPkg, PackageManager.GET_META_DATA);
if (replacedInfo != null) {
final CharSequence loadLabel = replacedInfo.loadLabel(pm);
Log.d(TAG, "replace from [" + info.packageName + "] to [" + replacedPkg + "]");
Log.d(TAG, "replace from [" + info.loadLabel(pm) + "] to [" + loadLabel + "]");
return loadLabel;
}
} catch (NameNotFoundException e) {
e.printStackTrace();
}
}
}
return info.loadLabel(pm);
}
public static CharSequence loadUnsafeLabel(PackageManager pm, String fromPkgName, int labelRes,
ApplicationInfo appinfo) {
String toPkgName = getReplacedPkg(fromPkgName);
Log.d(LabelManager.TAG, "loadUnsafeLabel toPkgName:" +toPkgName);
if (toPkgName != null) {//改应用属于是要被替代的应用
ApplicationInfo applicationInfo = null;
try {
//使用替代的ApplicationInfo
applicationInfo = pm.getApplicationInfo(toPkgName, PackageManager.GET_META_DATA);
} catch (NameNotFoundException e) {
e.printStackTrace();
}
Log.d(LabelManager.TAG, "loadUnsafeLabel applicationInfo:" +applicationInfo);
if (applicationInfo != null) {
//获取目标App的应用名称
CharSequence toLabel = pm.getText(toPkgName, labelRes, applicationInfo);
Log.d(LabelManager.TAG, "loadUnsafeLabel replace[" + fromPkgName + "] to " + toPkgName + " label:" + toLabel);
if (toLabel != null) {
return toLabel.toString().trim();
}
}
}
return pm.getText(fromPkgName, labelRes, appinfo);
}
}
应用名称映射效果图
应用名称替换效果.png
解决方案 2
通过动态资源覆盖的方式，实现，参考章节：
优缺点：
方案一：
优点：每次修改资源，只需修改和编译ResApp，方便改动和发布
缺点：ResApp中的资源文件属性，需要跟MainApp保持一次，不能删除和增加属性字段；
需要修改系统，虽然改动不大
方案二：
优点：只需添加要覆盖的资源文件即可
缺点：每次资源改动，需要重新编译系统，改动和发布比较麻烦
