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.