Android学习七：new Date使用

package com.example.datetime;

import java.text.SimpleDateFormat;
import java.util.Date;

import android.app.Activity;
import android.app.AlertDialog;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class DatetimeActivity extends Activity implements OnClickListener
{// 注意这里实现了OnClickListener接口
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_datetime);
        Button btnShowDate = (Button) findViewById(R.id.btnShowDate);
        Button btnShowTime = (Button) findViewById(R.id.btnShowTime);

        //注意这里的监听器方法
        btnShowDate.setOnClickListener(this);
        btnShowTime.setOnClickListener(this);
    }

    @Override
    public void onClick(View v)
    {
        //注意这里的单击事件的处理方法
        SimpleDateFormat sdf = null;
        switch (v.getId())
        {
        case R.id.btnShowDate:
            sdf = new SimpleDateFormat("yyyy-MM-dd");
            showDialog("當前日期", sdf.format(new Date()));
            break;
        case R.id.btnShowTime:
            sdf = new SimpleDateFormat("HH:mm:ss");
            showDialog("當前時間", sdf.format(new Date()));
            break;
        }

    }

    //窗口弹出
    private void showDialog(String title, String msg)
    {
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle(title);
        builder.setMessage(msg);
        builder.create().show();
    }
}