android基本定时器和延时的用法,总结一下比较简洁的模式,方便简单地在程序中直接调用。
一、定时循环
1. handler.postDelayed+Runnable
- 首先创建一个Handler对象
Handler handler=new Handler();
- 然后创建一个Runnable对象
Runnable runnable=new Runnable(){
@Override
public void run() {
// TODO Auto-generated method stub
//要做的事情,这里再次调用此Runnable对象,以实现每两秒实现一次的定时器操作
handler.postDelayed(this, 2000);
}};
- 主线程中调用,使用PostDelayed方法,两秒后调用此Runnable对象
handler.postDelayed(runnable, 2000);
- ★ 关闭此定时器,可以这样操作
handler.removeCallbacks(runnable);
2. handler+timer+timeTask
- 首先创建一个Handler对象
Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
if (msg.what == 1){
//do something
}
super.handleMessage(msg);
}
};
- 然后创建一个Timer 对象
Timer timer = new Timer();
TimerTask timerTask = new TimerTask() {
@Override
public void run() {
Message message = new Message();
message.what = 1;
handler.sendMessage(message);
}
};
- 主线程中调用,使用schedule方法
//延时1s,每隔500毫秒执行一次run方法
timer.schedule(timerTask,1000,500);
3. Thread+handler
- 首先创建一个Handler对象
Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
if (msg.what == 1){
//do something
}
super.handleMessage(msg);
}
};
- 然后创建一个Timer 对象
class ScheduleThread extends Thread {//这里也可用Runnable接口实现
@Override
public void run() {
while (true){
try {
//每隔1s执行一次
Thread.sleep(1000);
Message msg = new Message();
msg.what = 1;
handler.sendMessage(msg);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
- 主线程中调用
new Thread(new ScheduleThread ()).start();
二、延时
1. Handler的postDelayed方法:
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
//do something
}
}, 1000); //延时1s执行
2. Timer + TimerTask方法:
timer = new Timer();
timer.schedule(new TimerTask() {
@Override
public void run() {
//do something
}
},1000);//延时1s执行
3. Thread方法:
new Thread(new Runnable() {
@Override
public void run() {
try {
Thread.sleep(1000);//延时1s
//do something
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}).start();
new Thread(new MyThread()).start();