最近公司又要求做一个签到日历效果，我为啥加个又是之前我实现了一个日历签到效果，而这次我使用的则是RecycleView去实现。
实现思路 初始化日历数据，把数据传入到适配器中并显示。 至于左右滑动页面刷新，重写RecyclerView的onTouchEvent方法，监听手势的改变，然后更改list数据，重新显示UI。
在这里借鉴了一下 ToMyBestLove 所写的博客，并完善了一下方法，方便定制化处理。
核心代码 CalendarTool 这个工具类确实不错，可以获取正确的日期，很棒的算法可以减少大家不必要的时间。
代码语言：javascript复制public class CalendarTool<T extends BaseDateEntity> {
private final String TAG = CalendarTool.class.getSimpleName();
public static int FLING_MIN_DISTANCE = 100;
private final int[] weekDayRow = {0, 1, 2, 3, 4, 5, 6};
private ArrayList<DateEntity> mDataList = new ArrayList<>();//日期数组
private ArrayList<T> mRecordList;//事件记录数组
private DateEntity mDateEntity;
private int mYear;
private int mMonth;
private boolean mEndBelong;
private boolean mStartBelong;
private int mStartDay;
private int mEndDay;
/**
* 当前年月日
*/
private int mCurrenYear;
private int mCurrenMonth;
private int mCurrenDay;
/**
* 平年月天数数组
*/
int commonYearMonthDay[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
/**
* 闰年月天数数组
*/
int leapYearMonthDay[] = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
public CalendarTool() {
/** 初始化当前系统的日期 */
Calendar calendar = Calendar.getInstance();
mCurrenYear = calendar.get(Calendar.YEAR);
mCurrenMonth = calendar.get(Calendar.MONTH) 1;
mCurrenDay = calendar.get(Calendar.DAY_OF_MONTH);
this.mYear = mCurrenYear;
this.mMonth = mCurrenMonth;
}
/**
* 获取当前日历的年月 x为年，y为月
*/
public Point getNowCalendar() {
Point p = new Point(mYear, mMonth);
return p;
}
/**
* 判断第一天属不属于本月
*/
public boolean isStartBelong() {
return mStartBelong;
}
/**
* 判断最后一天属不属于本月
*/
public boolean isEndBelong() {
return mEndBelong;
}
/**
* 获取日历第一天的日期
*/
public int getStartDay() {
return mStartDay;
}
/**
* 获取日历最后一天的日期
*/
public int getEndDay() {
return mEndDay;
}
public ArrayList<DateEntity> initDateList() {
return initDateList(mYear, mMonth);
}
public void initRecordList(ArrayList<T> recordList) {
mRecordList = recordList;
}
/**
* 通过年月获取当前页面的日期集合
*/
private ArrayList<DateEntity> initDateList(int year, int month) {
Log.i(TAG, "initDateList: year = " year " month = " month);
mDataList.clear();
/** 修改部分 */
int endDate = 0;// 得到上一个月的天数，作为上一个月在本日历的结束日期
if ((year - 1) == this.mYear || month == 1) {// 说明向前翻了一年，那么上个月的天数就应该是上一年的12月的天数，或者到翻到一月份的时候，那么上一个月的天数也是上一年的12月份的天数
endDate = this.getDays(year - 1, 12);
} else {// 得到上一个月的天数，作为上一个月在本日历的结束日期
endDate = this.getDays(year, month - 1);
}
/** 修改部分结束 */
this.mYear = year;// 当前日历上显示的年
this.mMonth = month;// 当前日历上显示的月
int days = this.getDays(year, month);// 得到本月的总共天数
int dayOfWeek = this.getWeekDay(year, month);//得到当前年月的第一天为星期几
int selfDaysEndWeek = 0;// 本月的最后一天是星期几
mStartBelong = true;
/** 先添加前面不属于本月的 */
if (dayOfWeek != 0) {
int startDate = endDate - dayOfWeek 1;// 当前月的上一个月在本日历的开始日期
for (int i = startDate, j = 0; i <= endDate; i , j ) {
mDateEntity = new DateEntity(year, month - 1, i);
mDateEntity.date = mDateEntity.year * 10000 mDateEntity.month * 100 i;
if (startDate == i) {
mStartBelong = false;
mStartDay = mDateEntity.date;
}
mDateEntity.isSelfMonthDate = false;
mDateEntity.weekDay = weekDayRow[j];
mDateEntity.hasRecord = hasRecord(mDateEntity.date);
mDataList.add(mDateEntity);
}
}
/** 添加本月的 */
for (int i = 1, j = dayOfWeek; i <= days; i , j ) {
mDateEntity = new DateEntity(year, month, i);
mDateEntity.date = mDateEntity.year * 10000 mDateEntity.month * 100 i;
if (mStartBelong && i == 1) {
mStartDay = mDateEntity.date;
}
if (i == days) {
mEndDay = mDateEntity.date;
}
mDateEntity.isSelfMonthDate = true;
if (j >= 7) {
j = 0;
}
selfDaysEndWeek = j;
mDateEntity.weekDay = weekDayRow[j];
if (year == mCurrenYear && month == mCurrenMonth && i == mCurrenDay) {
mDateEntity.isNowDate = true;
}
mDateEntity.hasRecord = hasRecord(mDateEntity.date);
mDataList.add(mDateEntity);
}
mEndBelong = true;
/*** 添加后面下一个月的 */
for (int i = 1, j = selfDaysEndWeek 1; i < 7; i , j ) {
if (j >= 7) {
break;
}
mEndBelong = false;
mDateEntity = new DateEntity(year, month 1, i);
if (mDateEntity.month > 12) {
mDateEntity.year = year 1;
mDateEntity.month = 1;
}
mDateEntity.date = mDateEntity.year * 10000 mDateEntity.month * 100 i;
mDateEntity.isSelfMonthDate = false;
mDateEntity.weekDay = weekDayRow[j];
mDateEntity.hasRecord = hasRecord(mDateEntity.date);
mDataList.add(mDateEntity);
mEndDay = mDateEntity.year * 10000 mDateEntity.month * 100 i;
}
return mDataList;
}
/**
* 通过年月，获取这个月一共有多少天
*/
private int getDays(int year, int month) {
int days = 0;
if ((year % 4 == 0 && (year % 100 != 0)) || (year % 400 == 0)) {
if (month > 0 && month <= 12) {
days = leapYearMonthDay[month - 1];
}
} else {
if (month > 0 && month <= 12) {
days = commonYearMonthDay[month - 1];
}
}
return days;
}
private boolean hasRecord(int date) {
if (mRecordList != null) {
for (T baseDateEntity : mRecordList) {
if (baseDateEntity.year * 10000 baseDateEntity.month * 100 baseDateEntity.day == date) {
return true;
}
}
}
return false;
}
/**
* 通过年，月获取当前月的第一天为星期几 ，返回0是星期天，1是星期一，依次类推
*/
private int getWeekDay(int year, int month) {
int dayOfWeek;
int goneYearDays = 0;
int thisYearDays = 0;
boolean isLeapYear = false;//闰年
int commonYearMonthDay[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
int leapYearMonthDay[] = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
for (int i = 1900; i < year; i ) {// 从1900年开始算起，1900年1月1日为星期一
if ((i % 4 == 0 && (i % 100 != 0)) || (i % 400 == 0)) {
goneYearDays = goneYearDays 366;
} else {
goneYearDays = goneYearDays 365;
}
}
if ((year % 4 == 0 && (year % 100 != 0)) || (year % 400 == 0)) {
isLeapYear = true;
for (int i = 0; i < month - 1; i ) {
thisYearDays = thisYearDays leapYearMonthDay[i];
}
} else {
isLeapYear = false;
for (int i = 0; i < month - 1; i ) {
thisYearDays = thisYearDays commonYearMonthDay[i];
}
}
dayOfWeek = (goneYearDays thisYearDays 1) % 7;
Log.d(this.getClass().getName(), "从1990到现在有" (goneYearDays thisYearDays 1) "天");
Log.d(this.getClass().getName(), year "年" month "月" 1 "日是星期" dayOfWeek);
return dayOfWeek;
}
public void flushDate(float distance_x) {
if (distance_x < 0) {// Fling right
if (mMonth 1 > 12) {
mDataList = initDateList(mYear 1, 1);
} else {
mDataList = initDateList(mYear, mMonth 1);
}
} else {// Fling left
if (mMonth - 1 <= 0) {
mDataList = initDateList(mYear - 1, 12);
} else {
mDataList = initDateList(mYear, mMonth - 1);
}
}
}
}initDateList方法，会根据当前传入的年月数据来计算当前日历该显示的数据。
因为我的需求是点击按钮完成签到即可，不用点击日历中的日期（item），只需要把当前的日期传入即可
代码语言：javascript复制 Calendar calendar = Calendar.getInstance();
list.add(new BaseDateEntity(calendar.get(Calendar.YEAR), (calendar.get(Calendar.MONTH) 1),calendar.get(Calendar.DAY_OF_MONTH)));
rcDate.initRecordList(list);initRecordList 已经封装adapter刷新，不用担心传值后没有刷新。
这个Demo即使是新手直接可以使用，省去了大家阅读的时间，毕竟大家的时间宝贵，干就完了
GitHub源码地址
如果您觉得功能对您有所帮助，麻烦给我一颗小星星。 谢谢大家
