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Android实现计时与倒计时的方法汇总

2017-06-06 08:39 561 查看

方法一

Timer与TimerTask(Java实现)

public class timerTask extends Activity{
private int recLen = 11;
private TextView txtView;
Timer timer = new Timer();
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.timertask);
txtView = (TextView)findViewById(R.id.txttime);
timer.schedule(task, 1000, 1000);  // timeTask
}
TimerTask task = new TimerTask() {
@Override
public void run() {
runOnUiThread(new Runnable() {  // UI thread
@Override
public void run() {
recLen--;
txtView.setText(""+recLen);
if(recLen < 0){
timer.cancel();
txtView.setVisibility(View.GONE);
}
}
});
}
};
}

方法二

TimerTask与Handler(不用Timer的改进型)

public class timerTask extends Activity{
private int recLen = 11;
private TextView txtView;
Timer timer = new Timer();
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.timertask);
txtView = (TextView)findViewById(R.id.txttime);
timer.schedule(task, 1000, 1000);  // timeTask
}
final Handler handler = new Handler(){
@Override
public void handleMessage(Message msg){
switch (msg.what) {
case 1:
txtView.setText(""+recLen);
if(recLen < 0){
timer.cancel();
txtView.setVisibility(View.GONE);
}
}
}
};
TimerTask task = new TimerTask() {
@Override
public void run() {
recLen--;
Message message = new Message();
message.what = 1;
handler.sendMessage(message);
}
};
}

方法三

Handler与Message(不用TimerTask) 

public class timerTask extends Activity{
private int recLen = 11;
private TextView txtView;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.timertask);
txtView = (TextView)findViewById(R.id.txttime);
Message message = handler.obtainMessage(1);  // Message
handler.sendMessageDelayed(message, 1000);
}
final Handler handler = new Handler(){
public void handleMessage(Message msg){   // handle message
switch (msg.what) {
case 1:
recLen--;
txtView.setText("" + recLen);
if(recLen > 0){
Message message = handler.obtainMessage(1);
handler.sendMessageDelayed(message, 1000);  // send message
}else{
txtView.setVisibility(View.GONE);
}
}
super.handleMessage(msg);
}
};
}

方法四

Handler与Thread(不占用UI线程)

public class timerTask extends Activity{
private int recLen = 0;
private TextView txtView;
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.timertask);
txtView = (TextView)findViewById(R.id.txttime);
new Thread(new MyThread()).start();   // start thread
}
final Handler handler = new Handler(){   // handle
public void handleMessage(Message msg){
switch (msg.what) {
case 1:
recLen++;
txtView.setText("" + recLen);
}
super.handleMessage(msg);
}
};
public class MyThread implements Runnable{  // thread
@Override
public void run(){
while(true){
try{
Thread.sleep(1000);  // sleep 1000ms
Message message = new Message();
message.what = 1;
handler.sendMessage(message);
}catch (Exception e) {
}

方法五

Handler与Runnable(最简单型)   

public class timerTask extends Activity{
private int recLen = 0;
private TextView txtView;
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.timertask);
txtView = (TextView)findViewById(R.id.txttime);
handler.postDelayed(runnable, 1000);
}
Handler handler = new Handler();
Runnable runnable = new Runnable() {
@Override
public void run() {
recLen++;
txtView.setText("" + recLen);
handler.postDelayed(this, 1000);
}
};
}

计时与倒计时

方法1,方法2和方法3,都是倒计时

方法4,方法5,都是计时

计时和倒计时,都可使用上述方法实现(代码稍加改动)

UI线程比较

方法1,方法2和方法3,都是在UI线程实现的计时;

方法4和方法5,是另开Runnable线程实现计时

实现方式比较

方法1,采用的是Java实现,即Timer和TimerTask方式;

其它四种方法,都采用了Handler消息处理

推荐使用

如果对UI线程交互要求不很高,可以选择方法2和方法3

如果考虑到UI线程阻塞,严重影响到用户体验,推荐使用方法4,另起线程单独用于计时和其它的逻辑处理

方法5,综合了前几种方法的优点,是最简的

以上所述是小编给大家介绍的Android实现计时与倒计时的方法汇总值,希望对大家有所帮助,如果大家有任何疑问请给我留言,小编会及时回复大家的。在此也非常感谢大家对脚本之家网站的支持!

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标签:  android 计时 倒计时