Android 三种实现定时器详解及实现方法

方法一:Handler+Thread

package com.xunfang.handerDemo;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.widget.TextView;

/**
* handler定时器
*
* @author Smalt
*
*/
public class HanderDemoActivity extends Activity {
TextView tvShow;
private int i = 0;

@Override
public void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.main);
 tvShow = (TextView) findViewById(R.id.tv_show);
 new Thread(new ThreadShow()).start();
}

// handler类接收数据
Handler handler = new Handler() {
 public void handleMessage(Message msg) {
  if (msg.what == 1) {
   tvShow.setText(Integer.toString(i++));
   System.out.println("receive....");
  }
 };
};

// 线程类
class ThreadShow implements Runnable {

@Override
 public void run() {
  // TODO Auto-generated method stub
  while (true) {
   try {
    Thread.sleep(1000);
    Message msg = new Message();
    msg.what = 1;
    handler.sendMessage(msg);
    System.out.println("send...");
   } catch (Exception e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
    System.out.println("thread error...");
   }
  }
 }
}
}

方法二:Handler类自带的postDelyed

package com.xunfang.handerDemo;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.widget.TextView;

/**
* handler定时器使用postDelyed实现
*
* @author Smalt
*
*/
public class HanderDemoActivity extends Activity {
TextView tvShow;
private int i = 0;
private int TIME = 1000;

@Override
public void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.main);
 tvShow = (TextView) findViewById(R.id.tv_show);
 handler.postDelayed(runnable, TIME); //每隔1s执行
}

Handler handler = new Handler();
Runnable runnable = new Runnable() {

@Override
 public void run() {
  // handler自带方法实现定时器
  try {
   handler.postDelayed(this, TIME);
   tvShow.setText(Integer.toString(i++));
   System.out.println("do...");
  } catch (Exception e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
   System.out.println("exception...");
  }
 }
};

}

方法三:Handler+Timer+TimerTask

package com.xunfang.handerDemo;

import java.util.Timer;
import java.util.TimerTask;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.widget.TextView;

/**
* 定时器实现:Handler+Timer+TimerTask
*
* @author Smalt
*
*/
public class HanderDemoActivity extends Activity {
TextView tvShow;
private int i = 0;
private int TIME = 1000;

@Override
public void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.main);
 tvShow = (TextView) findViewById(R.id.tv_show);
 timer.schedule(task, 1000, 1000); // 1s后执行task,经过1s再次执行
}

Handler handler = new Handler() {
 public void handleMessage(Message msg) {
  if (msg.what == 1) {
   tvShow.setText(Integer.toString(i++));
  }
  super.handleMessage(msg);
 };
};
Timer timer = new Timer();
TimerTask task = new TimerTask() {

@Override
 public void run() {
  // 需要做的事:发送消息
  Message message = new Message();
  message.what = 1;
  handler.sendMessage(message);
 }
};
}