Question

我正在尝试将UIButton子类化为附加属性，但正如您可能已经猜到的那样，我发现“无法识别的选择器发送到实例”错误。

确切错误：[UIButton setAnnotPin：]：发送到实例的无法识别的选择器

以下是代码的重要部分：

MapViewController.h：

  #import "UIRightPinAccessoryButton.h"

MapViewController.m：

- (MKAnnotationView *) mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>) annotation{ 
 //some other code..

UIRightPinAccessoryButton *rightAccessoryButton = [UIRightPinAccessoryButton buttonWithType:UIButtonTypeDetailDisclosure];
rightAccessoryButton.frame = CGRectMake(0, 0, 35, 35);
rightAccessoryButton.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;
rightAccessoryButton.contentHorizontalAlignment = UIControlContentHorizontalAlignmentCenter;
[rightAccessoryButton addTarget:self action:@selector(rightAccessoryButtonTapped:) forControlEvents:UIControlEventTouchUpInside]; 

rightAccessoryButton.annotPin = annot;  **// Error comes here**
}

这是我的UIRightPinAccessoryButton类：

UIRightPinAccessoryButton.h

#import "Annotations.h"

@interface UIRightPinAccessoryButton : UIButton{
  Annotations *annotPin;
} 

@property (nonatomic) Annotations *annotPin;

UIRightPinAccessoryButton.m

#import "UIRightPinAccessoryButton.h"

@implementation UIRightPinAccessoryButton

@synthesize annotPin;

@end

我真的不明白为什么xcode在UIButton上寻找setAnnotPin：方法而不是我的自定义UIRightPinAccessoryButton？

Answer 1

本节[UIRightPinAccessoryButton buttonWithType:UIButtonTypeDetailDisclosure];

不会返回UIRightPinAccessoryButton类型的对象，但会返回UIButton类型的对象所以把它改成

UIRightPinAccessoryButton *rightAccessoryButton = [[UIRightPinAccessoryButton alloc] init];

此外，似乎没有办法将按钮的类型更改为UIButtonTypeDetailDisclosure一旦其子类，您可以设置自己的图像，使其看起来相同但你也不能轻易地将buttonWithType子类化，请从iPhone: Override UIButton buttonWithType to return subclass

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自定义UIButton，无法识别的选择器发送到实例

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