android闹钟（四）：实现计时器

TimerView.java

package com.mytest.myclock;

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

import android.app.AlertDialog;
import android.content.Context;
import android.os.Handler;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.TextView;

public class TimerView extends LinearLayout {

public TimerView(Context context) {
super(context);
// TODO Auto-generated constructor stub
}

public TimerView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
// TODO Auto-generated constructor stub
}

public TimerView(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
}

private TextView tvHour;
private TextView tvMinute;
private TextView tvSecond;
private Button btnStart;
private Button btnStop;

@Override
protected void onFinishInflate() {
// TODO Auto-generated method stub
super.onFinishInflate();
init();

}

private void init() {
tvHour = (TextView) this.findViewById(R.id.timer_hour);
tvMinute = (TextView) this.findViewById(R.id.timer_mini);
tvSecond = (TextView) this.findViewById(R.id.timer_second);
btnStart = (Button) this.findViewById(R.id.btn_start_timer);
btnStop = (Button) this.findViewById(R.id.btn_stop_timer);

btnStop.setOnClickListener(new View.OnClickListener() {

@Override
public void onClick(View v) {
stopTimer();
}
});

btnStart.setOnClickListener(new View.OnClickListener() {

@Override
public void onClick(View v) {
startTimer();
}
});
}

private final int WORK_STATE_STOP = 0; // 计时状态，停止
private final int WORK_STATE_RUN = 1;// 计时状态
private int userInputTime = 0;
private Timer timer;
private TimerTask task;

private Handler handler = new Handler() {

public void handleMessage(android.os.Message msg) {

switch(msg.what){
case WORK_STATE_RUN:
int hour =  userInputTime/60/60;
int minute = (userInputTime/60)%60;
int second = userInputTime%60;
tvHour.setText(""+hour);
tvMinute.setText(""+minute);
tvSecond.setText(""+second);
break;
case WORK_STATE_STOP:
new AlertDialog.Builder(getContext()).setTitle("时间到").setNegativeButton("取消", null).show();
stopTimer();
break;
}
};
};

private void startTimer() {

try {
userInputTime = (Integer.parseInt(tvHour.getText().toString()) * 60 * 60
+ Integer.parseInt(tvMinute.getText().toString()) * 60
+ Integer.parseInt(tvSecond.getText().toString()));
} catch (Exception e) {
Log.e("info", "TimerView->startTimer"+ e.getMessage());
return;
}

timer = new Timer();
task = new TimerTask() {

@Override
public void run() {

userInputTime--;
handler.sendEmptyMessage(WORK_STATE_RUN);
if(userInputTime <=0){
handler.sendEmptyMessage(WORK_STATE_STOP);
stopTimer();
}

}
};
timer.schedule(task, 1000,1000); //延迟一秒，再每隔一秒执行一次timertask.run()
}

private void stopTimer() {
if(task!=null){
task.cancel();
task = null;
}
}

}

View Code

小结：

1、采用timer和timertask去刷新时间；

2、获取小时数应该采用hour = userInputTime/60/60，而不能直接hour = userInputTime/360.