android Timer and TImerTask Caused by: java.lang.IllegalStateException: TimerTask is scheduled already E/AndroidRuntime(31290): at java.util.Timer.scheduleImpl(Timer.java:569) E/AndroidRuntime(31290): at java.util.Timer.schedule(Timer.java:478)…
什么是Handler? Android 的官方解释: 文档分节1:A Handler allows you to send and process Message and Runnable objects associated with a thread's MessageQueue. Each Handler instance is associated with a single thread and that thread's message queue. When you create…
Android考虑到线程安全问题,不允许在线程中执行UI线程,在Android中,有一个类:android.os.Handler,这个可以实现各处线程间的消息传递.先看段代码,这个实例化了一个Handler,Handler可以通过Message在多个线程通讯,这里做的是定时recLen加1,然后以一定的格式,显示到recTime上(UI线程上的操作). 1 final Handler handler = new Handler(){ 2 public void handleMess…