Timer计时器、schedule、scheduleAtFixedRate、简单Calendar时钟

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="com.example.timertaskdemo.MainActivity" >

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" />

    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" />
    <TextView
        android:id="@+id/textView3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" />
    <TextView
        android:id="@+id/textView4"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" />
</LinearLayout>

MainActivity

package com.example.timertaskdemo;

import java.util.Calendar;
import java.util.Date;
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.util.Log;
import android.widget.TextView;

public class MainActivity extends Activity {
	TextView textView1;
	TextView textView2;
	TextView textView3;
	TextView textView4;

	private Timer timer1;
	private Timer timer2;
	private Timer timer3;
	private Timer timer4;

	private Date time;
	private Handler mHandler = new Handler() {
		@Override
		public void handleMessage(Message msg) {
			super.handleMessage(msg);
			if (msg.what == 1) {
				textView1.setText("11111");
				Log.e("TAG", "11111");

			}
			if (msg.what == 2) {
				textView2.setText("22222");
				Log.e("TAG", "22222");
			}

			if (msg.what == 3) {
				textView3.setText("33333");
				Log.e("TAG", "33333");
			}
			if (msg.what == 4) {
				Calendar calendar = Calendar.getInstance();
				calendar.set(Calendar.YEAR, calendar.get(Calendar.YEAR)); // 控制时
				calendar.set(Calendar.MONTH, calendar.get(Calendar.MONTH)); // 控制分
				calendar.set(Calendar.DATE, calendar.get(Calendar.DATE)); // 控制秒

				calendar.set(Calendar.HOUR_OF_DAY,
						calendar.get(Calendar.HOUR_OF_DAY));
				calendar.set(Calendar.MINUTE, calendar.get(Calendar.MINUTE));
				calendar.set(Calendar.SECOND, calendar.get(Calendar.SECOND));

				time = calendar.getTime();

				textView4.setText("" + time);
				Log.e("TAG", "44444");
			}
		}
	};

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		textView1 = (TextView) findViewById(R.id.textView1);
		textView2 = (TextView) findViewById(R.id.textView2);
		textView3 = (TextView) findViewById(R.id.textView3);
		textView4 = (TextView) findViewById(R.id.textView4);

		timer1();
		timer2();
		timer3();
		timer4();
	}

	@Override
	protected void onDestroy() {
		super.onDestroy();
		timer1.cancel();
		timer2.cancel();
		timer3.cancel();
		timer4.cancel();
	}

	/**
	 * 2秒后开始执行，执行完毕结束
	 */
	public void timer1() {
		timer1 = new Timer();
		timer1.schedule(new TimerTask() {
			public void run() {
				mHandler.sendEmptyMessage(1);
			}
		}, 2000);
	}

	/**
	 * 2秒后开始执行，执行完毕，过2秒继续循环
	 */
	public void timer2() {
		timer2 = new Timer();
		timer2.schedule(new TimerTask() {
			public void run() {
				mHandler.sendEmptyMessage(2);
			}
		}, 2000, 2000);
	}

	/**
	 * 2秒后开始执行，执行完毕，过2秒继续循环
	 */

	public void timer3() {
		timer3 = new Timer();
		timer3.scheduleAtFixedRate(new TimerTask() {
			public void run() {
				mHandler.sendEmptyMessage(3);
			}
		}, 2000, 2000);
	}

	/**
	 * 安排指定的任务task在指定的时间firstTime开始进行重复的固定速率period执行．
	 */
	public void timer4() {
		Calendar calendar = Calendar.getInstance();
		calendar.set(Calendar.YEAR, calendar.get(Calendar.YEAR)); // 控制时
		calendar.set(Calendar.MONTH, calendar.get(Calendar.MONTH)); // 控制分
		calendar.set(Calendar.DATE, calendar.get(Calendar.DATE)); // 控制秒

		calendar.set(Calendar.HOUR_OF_DAY, calendar.get(Calendar.HOUR_OF_DAY));
		calendar.set(Calendar.MINUTE, calendar.get(Calendar.MINUTE));
		calendar.set(Calendar.SECOND, calendar.get(Calendar.SECOND));

		time = calendar.getTime();

		Log.e("TAG", "" + time);
		timer4 = new Timer();
		timer4.scheduleAtFixedRate(new TimerTask() {
			public void run() {
				mHandler.sendEmptyMessage(4);

			}
		}, time, 1000);// 这里设定将延时每天固定执行
	}
}

++++++++++++++++++++++++++++++++日期++++++++++++++++++++++++++++++++++++++++

DateUtil

package com.example.dateutildemo;

import android.annotation.SuppressLint;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.Locale;
import java.util.Random;
import java.util.TimeZone;

@SuppressLint("SimpleDateFormat")
public class DateUtil {
	@SuppressLint("SimpleDateFormat")
	public static final SimpleDateFormat simpleFormat = new SimpleDateFormat(
			"yyyy-MM-dd HH:mm");

	@SuppressLint("SimpleDateFormat")
	public static final SimpleDateFormat yearFormat = new SimpleDateFormat(
			"yyyy-MM-dd");

	public static final SimpleDateFormat simpleDateFormat = new SimpleDateFormat(
			"yyyy-MM-dd HH:mm:ss");

	public static final TimeZone tz = TimeZone.getTimeZone("GMT+8:00");

	static {
		simpleFormat.setTimeZone(tz);
		yearFormat.setTimeZone(tz);
		simpleDateFormat.setTimeZone(tz);
	}

	/**
	 * 获取特定格式的时间
	 * 
	 * @param type
	 * @return
	 */
	public static String getFormatDateTime(int type) {
		try {
			Calendar c = Calendar.getInstance();
			c.setTimeInMillis(System.currentTimeMillis());
			if (type == 1) {

				return yearFormat.format(c.getTime());
			}
			if (type == 2) {
				return simpleFormat.format(c.getTime());
			}
			if (type == 3) {
				return simpleDateFormat.format(c.getTime());
			}

		} catch (Exception e) {
			e.printStackTrace();
		}
		return "";
	}

}

MainActivity

package com.example.dateutildemo;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;

public class MainActivity extends Activity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		String yearFormat = DateUtil.getFormatDateTime(1);
		String simpleFormat = DateUtil.getFormatDateTime(2);
		String simpleDateFormat = DateUtil.getFormatDateTime(3);
		
		//2015-12-28 13:32:36
		Log.e("TAG", yearFormat);
		Log.e("TAG", simpleFormat);
		Log.e("TAG", simpleDateFormat);
		
		
		
	}

}