android 计算所在周所在月的前后日期

效果图：

使用了 一个时间相关的工具类

package com.yqy.yqy_date;

import android.util.Log;

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

/**
 * 时间工具类
 * @author YQY
 *
 */
public class ToolDateTime {

	/** 日期格式：yyyy-MM-dd HH:mm:ss **/
	public static final String DF_YYYY_MM_DD_HH_MM_SS = "yyyy-MM-dd HH:mm:ss";

	/** 日期格式：yyyy-MM-dd HH:mm **/
	public static final String DF_YYYY_MM_DD_HH_MM = "yyyy-MM-dd HH:mm";

	/** 日期格式：yyyy-MM-dd **/
	public static final String DF_YYYY_MM_DD = "yyyy-MM-dd";

	/** 日期格式：HH:mm:ss **/
	public static final String DF_HH_MM_SS = "HH:mm:ss";

	/** 日期格式：HH:mm **/
	public static final String DF_HH_MM = "HH:mm";

	private final static long minute = 60 * 1000;// 1分钟
	private final static long hour = 60 * minute;// 1小时
	private final static long day = 24 * hour;// 1天
	private final static long month = 31 * day;// 月
	private final static long year = 12 * month;// 年

	/** Log输出标识 **/
	private static final String TAG = ToolDateTime.class.getSimpleName();

	/**
	 * 将日期格式化成友好的字符串：几分钟前、几小时前、几天前、几月前、几年前、刚刚
	 *
	 * @param date
	 * @return
	 */
	public static String formatFriendly(Date date) {
		if (date == null) {
			return null;
		}
		long diff = new Date().getTime() - date.getTime();
		long r = 0;
		if (diff > year) {
			r = (diff / year);
			return r + "年前";
		}
		if (diff > month) {
			r = (diff / month);
			return r + "个月前";
		}
		if (diff > day) {
			r = (diff / day);
			return r + "天前";
		}
		if (diff > hour) {
			r = (diff / hour);
			return r + "个小时前";
		}
		if (diff > minute) {
			r = (diff / minute);
			return r + "分钟前";
		}
		return "刚刚";
	}

	/**
	 * 将日期以yyyy-MM-dd HH:mm:ss格式化
	 *
	 * @param dateL
	 *            日期
	 * @return
	 */
	public static String formatDateTime(long dateL) {
		SimpleDateFormat sdf = new SimpleDateFormat(DF_YYYY_MM_DD_HH_MM_SS);
		Date date = new Date(dateL);
		return sdf.format(date);
	}

	/**
	 * 将日期以yyyy-MM-dd HH:mm:ss格式化
	 *
	 * @param dateL
	 *            日期
	 * @return
	 */
	public static String formatDateTime(long dateL, String formater) {
		SimpleDateFormat sdf = new SimpleDateFormat(formater);
		return sdf.format(new Date(dateL));
	}

	/**
	 * 将日期以yyyy-MM-dd HH:mm:ss格式化
	 *
	 * @param dateL
	 *            日期
	 * @return
	 */
	public static String formatDateTime(Date date, String formater) {
		SimpleDateFormat sdf = new SimpleDateFormat(formater);
		return sdf.format(date);
	}

	/**
	 * 将日期字符串转成日期
	 *
	 * @param strDate
	 *            字符串日期
	 * @return java.util.date日期类型
	 */
	public static Date parseDate(String strDate) {
		DateFormat dateFormat = new SimpleDateFormat(DF_YYYY_MM_DD_HH_MM_SS);
		Date returnDate = null;
		try {
			returnDate = dateFormat.parse(strDate);
		} catch (ParseException e) {
			Log.v(TAG, "parseDate failed !");

		}
		return returnDate;

	}

	/**
	 * 获取系统当前日期
	 *
	 * @return
	 */
	public static Date gainCurrentDate() {
		return new Date();
	}

	/**
	 * 验证日期是否比当前日期早
	 *
	 * @param target1
	 *            比较时间1
	 * @param target2
	 *            比较时间2
	 * @return true 则代表target1比target2晚或等于target2，否则比target2早
	 */
	public static boolean compareDate(Date target1, Date target2) {
		boolean flag = false;
		try {
			String target1DateTime = ToolDateTime.formatDateTime(target1,
					DF_YYYY_MM_DD_HH_MM_SS);
			String target2DateTime = ToolDateTime.formatDateTime(target2,
					DF_YYYY_MM_DD_HH_MM_SS);
			if (target1DateTime.compareTo(target2DateTime) <= 0) {
				flag = true;
			}
		} catch (Exception e1) {
			System.out.println("比较失败，原因：" + e1.getMessage());
		}
		return flag;
	}

	/**
	 * 对日期进行增加操作
	 *
	 * @param target
	 *            需要进行运算的日期
	 * @param hour
	 *            小时
	 * @return
	 */
	public static Date addDateTime(Date target, double hour) {
		if (null == target || hour < 0) {
			return target;
		}

		return new Date(target.getTime() + (long) (hour * 60 * 60 * 1000));
	}

	/**
	 * 对日期进行相减操作
	 *
	 * @param target
	 *            需要进行运算的日期
	 * @param hour
	 *            小时
	 * @return
	 */
	public static Date subDateTime(Date target, double hour) {
		if (null == target || hour < 0) {
			return target;
		}

		return new Date(target.getTime() - (long) (hour * 60 * 60 * 1000));
	}

}

MainActivity

package com.yqy.yqy_date;

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

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.widget.TextView;

public class MainActivity extends Activity {
	private TextView tv_week, tv_month;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		tv_week = (TextView) findViewById(R.id.tv_week);
		tv_month = (TextView) findViewById(R.id.tv_month);

		Date mDate = new Date();
		Date sDate = null;
		Date eDate = null;
		String sstr = "";
		String estr = "";
		sDate = ToolDateTime.subDateTime(mDate, (mDate.getDay() - 1) * 24);
		for (int i = 0; i < 15; i++) {
			eDate = ToolDateTime.addDateTime(sDate, 6 * 24);
			sstr = ToolDateTime.formatDateTime(sDate,
					ToolDateTime.DF_YYYY_MM_DD);
			estr = ToolDateTime.formatDateTime(eDate,
					ToolDateTime.DF_YYYY_MM_DD);
			tv_week.append(sstr + "~" + estr + "\n");
			sDate = ToolDateTime.addDateTime(eDate, 24);
		}

		SimpleDateFormat format = new SimpleDateFormat(ToolDateTime.DF_YYYY_MM_DD);
		// 获取当前月第一天：

		String first = "";
		String last = "";

		for (int i = 0; i < 10; i++) {
			Calendar c = Calendar.getInstance();
			Calendar ca = Calendar.getInstance();
			c.add(Calendar.MONTH, i);
			c.set(Calendar.DAY_OF_MONTH, 1);// 设置为1号,当前日期既为本月第一天
			first = format.format(c.getTime());

			// 获取当前月最后一天
			ca.add(Calendar.MONTH, i);
			ca.set(Calendar.DAY_OF_MONTH,
					ca.getActualMaximum(Calendar.DAY_OF_MONTH));
			last = format.format(ca.getTime());
			tv_month.append(first+"~"+last+"\n");
		}

	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}

}

xml

<RelativeLayout 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:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <TextView
        android:id="@+id/tv_week"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <TextView
        android:id="@+id/tv_month"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_below="@+id/tv_week"
        android:layout_marginTop="28dp" />

</RelativeLayout>