情景:
我有跟踪iOS应用程序的费用,我将费用从费用明细视图控制器存储到表视图(带有提取结果控制器),该视图显示费用列表以及类别,金额和日期。我的实体“Money”中有一个日期属性,它是费用或收入的父实体。
问题:
我想要的是基本上对给定的一周,一个月或一年的费用进行分类,并将其显示为部分标题标题,例如:(10月1日至10月7日),它显示费用金额和相关的东西根据那个特定的一周。在该视图中提供了两个按钮,如果我按下右键,它将使一周增加一周(2012年10月1日至10月7日现在显示2012年10月8日 - 10月15日),同样左按钮将减少一周一个星期。
我将如何实现这一目标?我正在尝试以下代码 - 不起作用。
- (void)weekCalculation
{
NSDate *today = [NSDate date]; // present date (current date)
NSCalendar* calendar = [NSCalendar currentCalendar];
NSDateComponents* comps = [calendar components:NSYearForWeekOfYearCalendarUnit |NSYearCalendarUnit|NSMonthCalendarUnit|NSWeekCalendarUnit|NSWeekdayCalendarUnit fromDate:today];
[comps setWeekday:1]; // 1: Sunday
firstDateOfTheWeek = [[calendar dateFromComponents:comps] retain];
[comps setWeekday:7]; // 7: Saturday
lastDateOfTheWeek = [[calendar dateFromComponents:comps] retain];
NSLog(@" first date of week =%@", firstDateOfTheWeek);
NSLog(@" last date of week =%@", lastDateOfTheWeek);
firstDateOfWeek = [dateFormatter stringFromDate:firstDateOfTheWeek];
lastDateOfWeek = [dateFormatter stringFromDate:lastDateOfTheWeek];
}
递增日期的代码 -
- (IBAction)showNextDates:(id)sender
{
int addDaysCount = 7;
NSDateComponents *dateComponents = [[[NSDateComponents alloc] init] autorelease];
[dateComponents setDay:addDaysCount];
NSDate *newDate1 = [[NSCalendar currentCalendar]
dateByAddingComponents:dateComponents
toDate:firstDateOfTheWeek options:0];
NSDate *newDate2 = [[NSCalendar currentCalendar]
dateByAddingComponents:dateComponents
toDate:lastDateOfTheWeek options:0];
NSLog(@" new dates =%@ %@", newDate1, newDate2);
}
假设本周显示如此(2012年11月4日 - 2012年11月10日),我按下增量按钮,我在控制台中看到,日期更改为2012年11月11日和2012年11月17日,这是正确的,但如果我按再次增加按钮,它再次显示相同的日期(2012年11月11日和2012年11月17日)。
请帮帮我。
答案 0 :(得分:2)
在您的班级中将currentDate
声明为@property
。试试这个。
@property(nonatomic, retain) NSDate *currentDate;
最初设置
self.currentDate = [NSDate date];
在调用此方法之前。
- (void)weekCalculation
{
NSCalendar* calendar = [NSCalendar currentCalendar];
NSDateComponents* comps = [calendar components:NSYearForWeekOfYearCalendarUnit |NSYearCalendarUnit|NSMonthCalendarUnit|NSWeekCalendarUnit|NSWeekdayCalendarUnit fromDate:self.currentDate];
[comps setWeekday:1]; // 1: Sunday
firstDateOfTheWeek = [[calendar dateFromComponents:comps] retain];
[comps setWeekday:7]; // 7: Saturday
lastDateOfTheWeek = [[calendar dateFromComponents:comps] retain];
NSLog(@" first date of week =%@", firstDateOfTheWeek);
NSLog(@" last date of week =%@", lastDateOfTheWeek);
firstDateOfWeek = [dateFormatter stringFromDate:firstDateOfTheWeek];
lastDateOfWeek = [dateFormatter stringFromDate:lastDateOfTheWeek];
}
加载视图后self.currentDate
值应从showNextDates
更新。确保它没有在其他地方重置。
- (IBAction)showNextDates:(id)sender
{
int addDaysCount = 7;
NSDateComponents *dateComponents = [[[NSDateComponents alloc] init] autorelease];
[dateComponents setDay:addDaysCount];
NSDate *newDate1 = [[NSCalendar currentCalendar]
dateByAddingComponents:dateComponents
toDate:firstDateOfTheWeek options:0];
NSDate *newDate2 = [[NSCalendar currentCalendar]
dateByAddingComponents:dateComponents
toDate:lastDateOfTheWeek options:0];
NSLog(@" new dates =%@ %@", newDate1, newDate2);
self.currentDate = newDate1;
}
答案 1 :(得分:1)
我在一个旧项目中需要类似的东西,并通过下面的代码实现。它将此周日期设置为NSDate变量,并在每次按钮单击时添加/删除7天内的日期组件。这是代码:
NSCalendar *calendar = [NSCalendar currentCalendar];
[calendar setTimeZone:[NSTimeZone timeZoneWithAbbreviation:@"GMT"]];
NSDate *date = [NSDate date];
NSDateComponents *components = [calendar components:(NSYearCalendarUnit|NSWeekdayCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit) fromDate:date ];
//
[components setDay:([components day] - ([components weekday] )+2)];
self.currentDate = [calendar dateFromComponents:components];
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
formatter.dateFormat = @"dd.MM.yyyy HH:mm:ss";
self.datelabel.text = [formatter stringFromDate:self.currentDate];
上面的代码计算本周开始并将其设置为currentDate变量。我有两个名为prevClick和nextClick的UIBut UIButtons调用设置下一个或上一个周开始的方法:
- (IBAction)prevClick:(id)sender {
[self addRemoveWeek:NO];
}
-(void)addRemoveWeek:(BOOL)add{
NSCalendar *calendar = [NSCalendar currentCalendar];
[calendar setTimeZone:[NSTimeZone timeZoneWithAbbreviation:@"GMT"]];
NSDateComponents *components = [calendar components:(NSYearCalendarUnit|NSWeekdayCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit) fromDate:self.currentDate ];
components.day = add?components.day+7:components.day-7;
self.currentDate = [calendar dateFromComponents:components];
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
formatter.dateFormat = @"dd.MM.yyyy HH:mm:ss";
self.datelabel.text = [formatter stringFromDate:self.currentDate];
}
- (IBAction)nextClk:(id)sender {
[self addRemoveWeek: YES];
}