calendar1.cpp

Trolltech公司发布的图形界面操作系统。可在qt-embedded-2.3.7平台上编译为嵌入式图形界面操作系统。

/**********************************************************************
** Copyright (C) 2000-2002 Trolltech AS.  All rights reserved.
**
** This file is part of the Qtopia Environment.
**
** This file may be distributed and/or modified under the terms of the
** GNU General Public License version 2 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
** See http://www.trolltech.com/gpl/ for GPL licensing information.
**
** Contact [e-mail] if any conditions of this licensing are
** not clear to you.
**
**********************************************************************/
#include <qtopia/calendar.h>
#include <qapplication.h>

/*!
  Returns a list of 42 dates (6 weeks) that cover the given \a month and
  \a year.

  The list starts on the Monday on or before the 1st of the month if 
  \a startWithMonday is TRUE, otherwise the list starts on the Sunday on 
  or before the 1st of the month.
*/
QValueList<QDate> Calendar::datesOfMonth( int year, int month,
						 bool startWithMonday )
{
    QDate thisMonth(year, month, 1);
    QDate currentDate = addMonths(-1, thisMonth);
    int firstDay = thisMonth.dayOfWeek();

    QValueList<QDate> days;    

    if ( startWithMonday )
	firstDay--;
    if (firstDay == 7)
	firstDay = 0;
    // firstDay is now index of first day of speced month.
    
    currentDate.setYMD(currentDate.year(), currentDate.month(),
	    currentDate.daysInMonth() - firstDay);
    // last day if not to be shown, day before etc if one to be shown...

    for (int i = 0; i < 6 * 7; i++) {
	currentDate = currentDate.addDays(1);
	days.append(currentDate);
    }

    return days;
}

/*!
    Using the calender page given by datesOfMonth() will return the 
    date at the position \a row, \a col, for the given \a month and \a year.

  The page starts on the Monday on or before the 1st of the month if 
  \a startWithMonday is TRUE, otherwise the page starts on the Sunday on 
  or before the 1st of the month.
*/
QDate Calendar::dateAtCoord( int year, int month, 
	int row, int col, bool startWithMonday)
{
    int pos = row*7 + col;
    return dateAtIndex(year, month, pos, startWithMonday);
}

/*!
    Using the calender page given by datesOfMonth() will return the 
    date at the position \a index for the given \a month and \a year.

  The page starts on the Monday on or before the 1st of the month if 
  \a startWithMonday is TRUE, otherwise the page starts on the Sunday on 
  or before the 1st of the month.
*/
QDate Calendar::dateAtIndex( int year, int month, int index,
	bool startWithMonday)
{
    QDate thisMonth(year, month, 1);
    QDate currentDate = addMonths(-1, thisMonth);
    int firstDay = thisMonth.dayOfWeek();

    if ( startWithMonday )
	firstDay--;
    if (firstDay == 7)
	firstDay = 0;
    // firstDay is now index of first day of speced month.

    currentDate.setYMD(currentDate.year(), currentDate.month(),
	    currentDate.daysInMonth() - firstDay);
    // last day if not to be shown, day before etc if one to be shown...


    return currentDate.addDays(index + 1);
}

/*!
  Returns the index for \a date on the calendar page given by datesOfMonth()
  for the given \a year and \a month.

  The page starts on the Monday on or before the 1st of the month if 
  \a startWithMonday is TRUE, otherwise the page starts on the Sunday on 
  or before the 1st of the month.
*/
int Calendar::indexForDate( int year, int month, const QDate &date, 
	bool startWithMonday)
{    
    QDate thisMonth(year, month, 1);
    QDate currentDate = addMonths(-1, thisMonth);
    int firstDay = thisMonth.dayOfWeek();

    if ( startWithMonday )
	firstDay--;
    if (firstDay == 7)
	firstDay = 0;
    // firstDay is now index of first day of speced month.

    currentDate.setYMD(currentDate.year(), currentDate.month(),
	    currentDate.daysInMonth() - firstDay);
    // last day if not to be shown, day before etc if one to be shown...

    int index = currentDate.daysTo(date) - 1;
    if (index > 41) return -1;
    if (index < 0) return -1;
    return index;
}

/*!
  Sets the \a row and \a col to the position for
  \a date on the calendar page given by datesOfMonth()
  for the given \a year and \a month.

  The page starts on the Monday on or before the 1st of the month if 
  \a startWithMonday is TRUE, otherwise the page starts on the Sunday on 
  or before the 1st of the month.
*/
void Calendar::coordForDate( int year, int month,
	const QDate &date, int &row, int &col,
	bool startWithMonday)
{
    int offset = indexForDate(year, month, date, startWithMonday);

    if (offset < 0) {
	row = col = -1;
    } else {
	row = offset / 7;
	col = offset % 7;
    }
}

/*!
  Returns the week number the date \a dt is in the month for that date.
  For instance the first Wednesday of the month is in the first week the second
  Wednesday in the month is in the second week and so on.
*/
int Calendar::weekInMonth(const QDate &dt)
{
    if (dt.day() == 1)
	return 1;
    return ((dt.day() - 1) / 7) + 1;
}

/*!
  Returns a date \a nmonths later than the date \a orig (or earlier if \a nmonths is negative).

  Rounds to the last day of month if the day of the calculated date would be
  invalid.
*/
QDate Calendar::addMonths(int nmonths, const QDate &orig)
{
    int y, m, d;
    y = orig.year();
    m = orig.month();
    d = orig.day();

    while ( nmonths != 0 ) {
	if ( nmonths < 0 && nmonths + 12 <= 0 ) {
	    y--;
	    nmonths+=12;
	} else if ( nmonths < 0 ) {
	    m+= nmonths;
	    nmonths = 0;
	    if ( m <= 0 ) {
		--y;
		m+=12;
	    }
	} else if ( nmonths - 12 >= 0 ) {
	    y++;
	    nmonths-=12;
	} else if ( m == 12 ) {
	    y++;
	    m = 0;
	} else {
	    m+= nmonths;
	    nmonths = 0;
	    if ( m > 12 ) {
		++y;
		m -= 12;
	    }
	}
    }

    QDate tmp(y,m,1);

    if( d > tmp.daysInMonth() )
	d = tmp.daysInMonth();

    QDate date(y, m, d);
    return date;
}

/*!
  Returns a date \a nyears later than the date \a orig (or earlier if \a nyears is negative).
*/
QDate Calendar::addYears( int nyears , const QDate &orig)
{
    int y, m, d;
    y = orig.year();
    m = orig.month();
    d = orig.day();

    y += nyears;
    QDate date(y, m, d);
    return date;
}