线程 1：EXC_BAD_ACCESS（代码=1，地址=0x5146a345）

Question

我正在尝试实现日历。我有一个年份标签和两个用于从日历递增和递减年份的按钮。我在单击按钮（递增或递减）时遇到此异常（Thread1：EXC_BAD_ACCESS（代码=1，地址=0x5146a345））我的要求是，如果我单击右键，我的年份应该增加，如果我单击左键按钮我的年份应该减少。我的例外行是 date = [cal dateByAddingUnit:NSCalendarUnitYear value:1 toDate:date options:0]; 你能帮忙解决这个问题吗？这是我的代码

   - (void)viewDidLoad
    {
        [super viewDidLoad];

        date = [NSDate date];
        NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
        [formatter setDateFormat:@"YYYY"];
        NSString *stringFromDate = [formatter stringFromDate:date];
        yar1.text=stringFromDate;

     }
    - (IBAction)right:(id)sender {

        NSCalendar *cal = [NSCalendar currentCalendar];

        date = [cal dateByAddingUnit:NSCalendarUnitYear value:1 toDate:date options:0];
        NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
        [formatter setDateFormat:@"YYYY"];
        NSString *stringFromDate = [formatter stringFromDate:date];
        yar1.text=stringFromDate;

       }
 - (IBAction)left:(id)sender {

        NSCalendar *cal = [NSCalendar currentCalendar];

        date = [cal dateByAddingUnit:NSCalendarUnitYear value:1 toDate:date options:0];
        NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
        [formatter setDateFormat:@"YYYY"];
        NSString *stringFromDate = [formatter stringFromDate:date];
        yar1.text=stringFromDate;

       }

Answer 1

你需要一个日期组件来像这样更改日期，

-(NSDate *)offsetYear:(int)numOfYears date:(NSDate*)date 
{
NSDateComponents *offsetComponents = [[NSDateComponents alloc] init];
[offsetComponents setYear:numOfYears];

return [[NSCalendar currentCalendar] dateByAddingComponents:offsetComponents
                              toDate:date options:0]; }

将偏移量传递为右侧为 1，左侧为 -1

线程 1：EXC_BAD_ACCESS（代码=1，地址=0x5146a345）

Thread1: EXC_BAD_ACCESS(code=1,address=0x5146a345)

calendar

increment

decrement

ios