<=Api 23 时 相信大家都是通过installPackage这个类反射来静默安装apk的。但是呢api24及其之后就没有这个方法了，你再PackageManagerService或IPackageManager都是没有这个方法了。所以我们只能通过installPacakageAsUser来实现静默安装了。代码如下：

/**

* void installPackageAsUser(in String originPath,

* in IPackageInstallObserver2 observer,

* int flags,

* in String installerPackageName,

* int userId);

* @param installPath

*/

private void installApkInSilence(String installPath,String packageName) {

Class> pmService;

Class> activityTherad;

Method method;

try {

activityTherad = Class.forName("android.app.ActivityThread");

Class> paramTypes[] = getParamTypes(activityTherad, "getPackageManager");

method = activityTherad.getMethod("getPackageManager", paramTypes);

Object PackageManagerService = method.invoke(activityTherad);

pmService = PackageManagerService.getClass();

Class> paramTypes1[] = getParamTypes(pmService, "installPackageAsUser");

method = pmService.getMethod("installPackageAsUser", paramTypes1);

method.invoke(PackageManagerService, installPath, null, 0x00000040, packageName, getUserId(Binder.getCallingUid()));//getUserId

} catch (ClassNotFoundException e) {

e.printStackTrace();

} catch (NoSuchMethodException e) {

e.printStackTrace();

} catch (IllegalAccessException e) {

e.printStackTrace();

} catch (InvocationTargetException e) {

e.printStackTrace();

}

}

private Class>[] getParamTypes(Class> cls, String mName) {

Class> cs[] = null;

Method[] mtd = cls.getMethods();

for (int i = 0; i < mtd.length; i++) {

if (!mtd[i].getName().equals(mName)) {

continue;

}

cs = mtd[i].getParameterTypes();

}

return cs;

}

public static final int PER_USER_RANGE = 100000;

public static int getUserId(int uid) {

return uid / PER_USER_RANGE;

}