android apk嵌套 从一个apk启动另外一个apk

a.apk-主应用 b.apk-被启动应用

主要思想：把b.apk放到assets目录下，由于有大小限制（1M），所以改名成b.mp3(因为mp3,jpg,png,mp4等不会检查，不会限制大小)，然后在用的时候再改回来

1.具体实现：

public void intallApp(Context context) {

try {

String path = context.getFilesDir().getAbsolutePath()+ "/b.apk"; //从assets中解压到这个目录

File f = new File(path);

if (!f.exists()) {

f.createNewFile();

}

InputStream is = context.getAssets().open("b.mp3");//assets里的文件在应用安装后仍然存在于apk文件中

inputStreamToFile(is, f);

String cmd = "chmod 777 " + f.getAbsolutePath();

Runtime.getRuntime().exec(cmd);

cmd = "chmod 777 " + f.getParent();

Runtime.getRuntime().exec(cmd);

// 尝试提升上2级的父文件夹权限，在阅读插件下载到手机存储时，刚好用到了2级目录

// /data/data/packagename/files/这个目录下面所有的层级目录都需要提升权限，才可安装apk，弹出安装界面

cmd = "chmod 777 " + new File(f.getParent()).getParent();

Runtime.getRuntime().exec(cmd);

Intent intent = new Intent();

intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

intent.setAction(android.content.Intent.ACTION_VIEW);

String type = "application/vnd.android.package-archive";

/* 设置intent的file与MimeType */

intent.setDataAndType(Uri.fromFile(f), type);

context.startActivity(intent);

} catch (ActivityNotFoundException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

}

public void inputStreamToFile(InputStream inputStream,File file){

///InputStream inputStream = null;

OutputStream outputStream = null;

try {

// read this file into InputStream

//inputStream = new FileInputStream("test.txt");

// write the inputStream to a FileOutputStream

outputStream = new FileOutputStream(file);

int read = 0;

byte[] bytes = new byte[1024];

while ((read = inputStream.read(bytes)) != -1) {

outputStream.write(bytes, 0, read);

}

System.out.println("Done!");

} catch (IOException e) {

e.printStackTrace();

} finally {

if (inputStream != null) {

try {

inputStream.close();

} catch (IOException e) {

e.printStackTrace();

}

}

if (outputStream != null) {

try {

// outputStream.flush();

outputStream.close();

} catch (IOException e) {

e.printStackTrace();

}

}

}

}

2.如果是启动已安装的应用，实现如下：

public boolean startApp(Context context, String packageName) {

//String packageName = "XXX";

Intent intent = new Intent(Intent.ACTION_MAIN, null);

intent.addCategory(Intent.CATEGORY_LAUNCHER);

PackageManager pm = context.getPackageManager();

List<ResolveInfo> listInfos = pm.queryIntentActivities(intent, 0);

String className = null;

for (ResolveInfo info : listInfos) {

if (packageName.equals(info.activityInfo.packageName)) {

className = info.activityInfo.name;

break;

}

}

if (className != null && className.length() > 0) {

intent.setComponent(new ComponentName(packageName, className));

intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK

| Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED);

context.startActivity(intent);

return true;

}

return false;

}

如果你知道包名,还知道作为启动的那activity的类名，就更简单了，就可以省掉上面查找的过程，直接启动。