Question

如何为UIButton分配辅助信息？
是否可以通过KVC技术分配：

- (void)viewDidLoad {
    [super viewDidLoad];
    NSNumber *dateNumb = [NSNumber numberWithInteger:15];
    [self.myButton setValue:dateNumb forKey:@"day"];
}

我收到以下错误：

***由于未捕获的异常终止应用程序＆＃39; NSUnknownKeyException＆＃39;，原因：＆＃39; ... setValue：forUndefinedKey：]：此类不是键值符合编码标准的关键日。＆＃39;

Answer 1

我可以通过UIButton的图层这样做;不是UIButton本身：

- (void)viewDidLoad {
    [super viewDidLoad];
    NSNumber *dateNumb = [NSNumber numberWithInteger:15];

    CALayer *myLayer = self.myButton.layer;
    [myLayer setValue:dateNumb forKey:@"day"];
      //  [self.myButton setValue:dateNumb forKey:@"day"];
}

(lldb) po sender.layer
<CALayer:0x7fb5f2819800; position = CGPoint (188 241); bounds = CGRect (0 0; 46 30); delegate = <UIButton: 0x7fb5f281abe0; frame = (165 226; 46 30); opaque = NO; 
autoresize = RM+BM; layer = <CALayer: 0x7fb5f2819800>>; 
sublayers = (<_UILabelLayer: 0x7fb5f178eba0>); 
allowsGroupOpacity = YES; day = 15>

通过KVC为UIButton分配辅助值

1 个答案: