请问怎么调用安卓原生的界面防劫持的代码呢？

安全检测公司提示说界面防劫持，提供了以下的示例代码，但我不知道如何在h5+中调用这行代码
请把以下android中的代码，转化为javascript页面中的代码：
@Override
protected void onPause() {
super.onPause();
String topActivityPackage = null;
ActivityManager activityManager = (ActivityManager)
(MyApplication.myContext.getSystemService(android.content.Context.ACTIVITY_SERVICE));
List<ActivityManager.RunningTaskInfo> runningTaskInfos =
activityManager
.getRunningTasks(1);
if (runningTaskInfos != null) {
ComponentName f = runningTaskInfos.get(0).topActivity;
topActivityPackage = f.getPackageName();
if(topActivityPackage.equalsIgnoreCase("自身应用包名")){ AlertDialog.Builder builder = new
AlertDialog.Builder(MainActivity.this); builder.setTitle("警告");
builder.setPositiveButton("检测到窗口被劫持" , null ); builder.show(); }
}
refresh();
}