Question

我正在尝试使用NSMutableDictionary将我的自定义类对象与UIButton配对，因为它是关键。作为键的UIButton也是我想要存储为NSMutableDictionary中对象的对象的成员。

我的班级定义如下：

@interface ClassA : NSObject {
@public
    UIButton *button1;
    UIButton *button2;
    UILabel *label;
}

@property (nonatomic, retain) UIButton *button1;
@property (nonatomic, retain) UIButton *button2;
@property (nonatomic, retain) UILabel *label;
@end

我的实施就是这样：

@implementation ClassA
@synthesize button1, button2, label;
@end

NSMutableDictionary在另一个类中。我在实现中定义它如下：

@interface UIClass1 : UIViewController {
    NSMutableDictionary *Dictionary;
}

-(void)DoWork;

@property (nonatomic, retain) NSMutableDictionary *Dictionary;
@end

我试图设置字典值的部分在这里完成：

-(void)DoWork{
    Dictionary = [[NSMutableDictionary alloc] init];
    ObjectA = [[ClassA alloc] init];

    ObjectA->button1 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    ObjectA->button2 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    ObjectA->label = [[[UILabel alloc] initWithFrame:CGRectMake(20, 20, 20, 20)] autorelease]

    /* THIS IS A TEST AND IT WORKS FINE */
    NSString *str = [[NSString alloc] initWithFormat:@"test"];
    [Dictionary setObject:obj1 forKey:str];

    /*THIS IS WHAT I WOULD ACTUALLY LIKE TO DO */
    [Dictionary setObject:Object1 forKey:ObjectA->button1];
    [Dictionary setObject:ObjectA forKey:ObjectA->button2];
}

我通过我的调试器跟踪了这段代码，当我到达这一行时：

[Dictionary setObject:Object1 forKey:ObjectA->button1];

它只会使SIGABRT崩溃。我的变量都不是零，每个对象都已分配。

为什么我不能从ClassA设置按钮键的任何想法，但我可以将它设置为我作为测试创建的NSString？

Answer 1

用作NSMutableDictionary中的键的对象必须符合NSCopying协议。

来自Apple文档：

价值的关键。密钥被复制（使用copyWithZone：;密钥必须符合NSCopying协议）。关键不能是零。

UIButton不符合NSCopying。

Answer 2

尝试使用

forKey:[NSValue valueWithPointer:ObjectA->button1]

NSMutableDIctionary setObject：当Key是Object的成员时，ForKey崩溃

2 个答案: