动态加载其他已经安装的apk的dex文件， 并通过反射执行，, private

动态加载其他已经安装的apk的dex文件， 并通过反射执行，, private

    private void useDexClassLoader(){                  //创建一个意图，用来找到指定的apk                  Intent intent = new Intent("com.suchangli.android.plugin", null);                  //获得包管理器                  PackageManager pm = getPackageManager();                  List<ResolveInfo> resolveinfoes =  pm.queryIntentActivities(intent, 0);                  //获得指定的activity的信息                  ActivityInfo actInfo = resolveinfoes.get(0).activityInfo;                  //获得包名                  String pacageName = actInfo.packageName;                  //获得apk的目录或者jar的目录                  String apkPath = actInfo.applicationInfo.sourceDir;                  //dex解压后的目录,注意，这个用宿主程序的目录，android中只允许程序读取写自己                  //目录下的文件                  String dexOutputDir = getApplicationInfo().dataDir;                  //native代码的目录                  String libPath = actInfo.applicationInfo.nativeLibraryDir;                  //创建类加载器，把dex加载到虚拟机中                  DexClassLoader calssLoader = new DexClassLoader(apkPath, dexOutputDir, libPath,                                  this.getClass().getClassLoader());                  //利用反射调用插件包内的类的方法                  try {                              Class<?> clazz = calssLoader.loadClass(pacageName+".Plugin1");                              Object obj = clazz.newInstance();                              Class[] param = new Class[2];                              param[0] = Integer.TYPE;                              param[1] = Integer.TYPE;                              Method method = clazz.getMethod("function1", param);                              Integer ret = (Integer)method.invoke(obj, 1,12);                              Log.i("Host", "return result is " + ret);                      } catch (ClassNotFoundException e) {                              e.printStackTrace();                      } catch (InstantiationException e) {                              e.printStackTrace();                      } catch (IllegalAccessException e) {                              e.printStackTrace();                      } catch (NoSuchMethodException e) {                              e.printStackTrace();                      } catch (IllegalArgumentException e) {                              e.printStackTrace();                      } catch (InvocationTargetException e) {                              e.printStackTrace();                      }          }