“未识别的选择器发送到实例”,其类继承自NSAttribute String

我有一个继承自 NSAttributedString 这样地:

#import <Foundation/Foundation.h>

@interface Text : NSAttributedString

-(id) initWithString:(NSString*) text andFont:(NSFont*)font andLineHeight:(float) lineHeight andLetterSpacing:(float) letterSpacing;

@end

文本m:

#import "Text.h"

#import <Cocoa/Cocoa.h>

@implementation Text

-(id) initWithString:(NSString*) text andFont:(NSFont*)font andLineHeight:(float) lineHeight andLetterSpacing:(float) letterSpacing
{
    NSMutableParagraphStyle* paragraphStyle = [[NSMutableParagraphStyle alloc] init];
    [paragraphStyle setParagraphStyle: [NSParagraphStyle defaultParagraphStyle]];
    paragraphStyle.lineHeightMultiple = lineHeight;
    NSDictionary* attributes =
    @{
        NSFontAttributeName: font,
        NSKernAttributeName: @(letterSpacing),
        NSParagraphStyleAttributeName: paragraphStyle
    };
    self = [super initWithString:text attributes:attributes];
    return self;
}

@end

当我像这样实例化类时:

[[Text alloc] initWithString:@"Test" andFont:welcomeLabelFont andLineHeight:52 andLetterSpacing:0.0f]];

我得到以下例外:

2017-07-17 17:21:15.771610+0300 Test[41403:10128169] -[Text initWithString:attributes:]: unrecognized selector sent to instance 0x600000000f70

选择器在基类中可用,事件ctrl单击它会跳转到 NSAttributedText 班谁能指出我做错了什么?参数不是零指针,调用似乎是合法的。唯一看起来奇怪的是错误有类名 Text NSAttribute字符串 .