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三种常用的定时器
Handler mHandler = new Handler();Runnable r = new Runnable() { @Override public void run() { //do something //每隔1s循环执行run方法 mHandler.postDelayed(this, 1000); }};主线程中调用：mHandler.postDelayed(r, 1000);//延时1000毫秒后启动mHandler.removeCallbacks(r); //停止计时 Handler handler = new Handler() { @Override public void handleMessage(Message msg) { if (msg.what == 1){ //do something } super.handleMessage(msg); } }; 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：timer.schedule(timerTask,1000,500);//延时1s，每隔500毫秒执行一次run方法 Handler handler = new Handler() { @Override public void handleMessage(Message msg) { if (msg.what == 1){ //do something } super.handleMessage(msg); } }; class MyThread extends Thread {//这里也可用Runnable接口实现 @Override public void run() { while (true){ try { Thread.sleep(1000);//每隔1s执行一次 Message msg = new Message(); msg.what = 1; handler.sendMessage(msg); } catch (InterruptedException e) { e.printStackTrace(); } } } }主线程中调用：new Thread(new MyThread()).start(); 三种延时执行的快捷方法：
new Handler().postDelayed(new Runnable() { @Override public void run() { //do something } }, 1000); //延时1s执行 timer = new Timer(); timer.schedule(new TimerTask() { @Override public void run() { //do something } },1000);//延时1s执行 new Thread(new MyThread()).start(); new Thread(new Runnable() { @Override public void run() { try { Thread.sleep(1000);//延时1s //do something } catch (InterruptedException e) { e.printStackTrace(); } } }).start();
package com.example.guessgame;import android.support.v7.app.ActionBarActivity;import android.os.Bundle;import android.view.Menu;import android.view.MenuItem;import android.view.View;import android.widget.*;public class MainActivity extends ActionBarActivity { private final int TIME_ALL=20; private int Time=TIME_ALL; private TextView info; private EditText input; private Button button; private int target; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); info = (TextView)findViewById(R.id.info); input = (EditText)findViewById(R.id.input); button = (Button)findViewById(R.id.button); button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { // TODO Auto-generated method stub if(button.getText().toString().equals("OK")){ mHandler.removeCallbacks(r); //停止计时 if(input.getText().toString().equals("")) return; int tmp = Integer.parseInt(input.getText().toString()); if(tmp == target){ info.setText("恭喜你，猜对了"); button.setText("再来一次！"); } else if(tmp < target) info.setText("猜小了，请重试"); else info.setText("猜大了，请重试"); } else newGame(); } }); newGame(); } Handler mHandler = new Handler(); Runnable r = new Runnable() { @Override public void run() { //do something Time--; if(Time==0) { info.setText("（计时"+TIME_ALL+"秒,当前："+Time+"），你已经超时了。"); } else if(Time>0) { info.setText("（计时"+TIME_ALL+"秒,当前："+Time+"）请输入1-100之间的数字："); } //每隔1s循环执行run方法 mHandler.postDelayed(this, 1000); } }; private void newGame(){ Time=TIME_ALL; mHandler.postDelayed(r, 1000);//延时1000毫秒后启动 info.setText("（计时"+TIME_ALL+"秒,当前："+Time+"）请输入1-100之间的数字："); input.setText(""); button.setText("OK"); target = (int)((Math.random())*99 + 1); } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { // Handle action bar item clicks here. The action bar will // automatically handle clicks on the Home/Up button, so long // as you specify a parent activity in AndroidManifest.xml. int id = item.getItemId(); if (id == R.id.action_settings) { return true; } return super.onOptionsItemSelected(item); }}
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