How to implement the Android timer function

In Android development, the timer generally has the following 3 ways to implement:

1, using handler and thread of sleep (long) method

2, the use of handler postdelayed (Runnable, Long) method

3, the use of handler and timer and TimerTask combination method

Here are the following:

The sleep (long) method using handle and thread

Handler is primarily used to handle received messages. This is only the main method, of course, there are other ways to achieve handler, interested in the API can be checked, there is not too much explanation.

1. Define a handler class to handle the received message.

New Handler () {    publicvoid  handlemessage (Message msg) {        //  Things to do        Super. Handlemessage (msg);}    };

2. Create a new thread class that implements the Runnable interface as follows:

 Public classMyThreadImplementsRunnable {@Override Public voidrun () {//TODO auto-generated Method Stub         while(true) {            Try{Thread.Sleep (10000);//thread paused for 10 seconds, per millisecondMessage message =NewMessage (); Message.what= 1; Handler.sendmessage (message);//Send Message}Catch(interruptedexception e) {//TODO auto-generated Catch blockE.printstacktrace (); }        }    }}

3. Add the following statement where you want to start the thread:

New Thread (new MyThread ()). Start ();

4. After the thread is started, the thread sends a message every 10s.

Second, using handler postdelayed (Runnable, Long) method

This implementation is relatively simple.

1. Define a handler class

Handler handler=New  Handler (); Runnable Runnable=new  Runnable () {    @Override    publicvoid  run () {        //  TODO auto-generated method stubs        // things        to do Handler.postdelayed (This, a);    }};

2. Start the timer

Handler.postdelayed (Runnable, 2000); // runnable is performed every two seconds.

3. Stop Timer

Handler.removecallbacks (runnable);

Third, the use of handler and timer and TimerTask combination method

1, define timer, timer task and handler handle

Private Final New  privatenew  Handler () {     @Override     publicvoid  handlemessage (Message msg) {         //  TODO auto-generated method stub          //         Super. Handlemessage (msg);}     ;

2. Initialize Timer task

New TimerTask () {     @Override     publicvoid  run () {         //         New  Message ();          = 1;         Handler.sendmessage (message);     } };

3. Start Timer

Timer.schedule (Task, 2000, 2000);

1. Timer task (TimerTask) as the name implies, that is, when the timer arrives at the specified time to do the work, here is to handler send a message, by the handler class for processing.

2. Java.util.Timer.schedule (timertask task, long delay): This method means that the task is executed after dalay/1000 seconds. Only once.

Java.util.Timer.schedule (timertask task, long delay, long period): This method is to say that the task is executed after delay/1000 seconds and then into period/ 1000 seconds to execute the task again, this is used for looping tasks, executed countless times, of course, you can use Timer.cancel (); Cancel the execution of the timer.

How to implement the Android timer function