ThreadTool和scheduled

1 随机线程池，若是须要有几个任务就开启几个线程来执行任务

ExecutorService service = Executors.newCachedThreadPool();

2 固定线程池

ExecutorService service = Executors.newFixedThreadPool(3);

3单线程，这个比传统线程的好处在于，线程销毁了，能够自动活过来

ExecutorService service = Executors.newSingleThreadExecutor();

定时调度的线程

 

@Override
	protected void onStart() {
		// TODO Auto-generated method stub
		super.onStart();
		scheduledExecutorService = Executors.newSingleThreadScheduledExecutor();
		//command 所要执行的任务
		//initialDelay  第一次启动时的延迟启动时间
		//period 每隔多少时间执行任务
		//unit 单位时间
		scheduledExecutorService.scheduleAtFixedRate(new ViewPagerTask(), 1, 2, TimeUnit.SECONDS);
	}
	@Override
	protected void onStop() {
		scheduledExecutorService.shutdown();
		super.onStop();
	}
    class ViewPagerTask implements Runnable{

		@Override
		public void run() {
			
			currentItem = (currentItem + 1)% images.size();
			handler.obtainMessage().sendToTarget();
		}
    	
    }
    Handler handler = new Handler(){

		@Override
		public void handleMessage(Message msg) {
			viewPager.setCurrentItem(currentItem);
		}
    	
    };