简单的倒计时软件的开发过程及心得

package com.lala.jishi;

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

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class MainActivity extends Activity implements OnClickListener{

private EditText inputet;
private Button getTime,startTime,stopTime;
private TextView time;
private int i = 0;
private Timer timer = null;
private TimerTask task = null;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    initView();
}

private void initView(){
    inputet = (EditText) findViewById(R.id.inputtime);
    getTime = (Button) findViewById(R.id.gettime);
    startTime = (Button) findViewById(R.id.starttime);
    stopTime = (Button) findViewById(R.id.stoptime);
    time = (TextView) findViewById(R.id.time);
    getTime.setOnClickListener(this);
    startTime.setOnClickListener(this);
    stopTime.setOnClickListener(this);
}

@Override
public void onClick(View v) {
    switch (v.getId()) {
    case R.id.gettime:
        time.setText(inputet.getText().toString());
        i = Integer.parseInt(inputet.getText().toString());
        break;

    case R.id.starttime:
        startTime();
        break;
    case R.id.stoptime:
        stopTime();
        break;
    }
}

private Handler mHandler = new Handler(){
    public void handleMessage(Message msg) {
        time.setText(msg.arg1+"");
        startTime();
    };
};

public void startTime(){
    timer = new Timer();
    task = new TimerTask() {

        @Override
        public void run() {
            i--;
            Message  message = mHandler.obtainMessage();
            message.arg1 = i;
            mHandler.sendMessage(message);
        }
    };
    timer.schedule(task, 1);
}

public void stopTime(){
    timer.cancel();
}

}