Question

我的项目中有很多viewcontrollers只是重定向到它的委托。所以我已经为它做了一个定义，但我对它的名字并不高兴。

你会如何命名，或者你会以另一种方式进行命名？

我也有委托可以返回对象或采取的情况多个论点。

// the problem is highly repetitive code    
-(void)switchToNextTab:(id)sender {

    SEL sel = @selector(switchToNextTab:);
    if([m_delegate respondsToSelector:sel]) {
        [m_delegate performSelector:sel withObject:self];
    }
}

-(void)switchToPrevTab:(id)sender {
    SEL sel = @selector(switchToPrevTab:);
    if([m_delegate respondsToSelector:sel]) {
        [m_delegate performSelector:sel withObject:self];
    }
}

-(void)closeTab:(id)sender {
    SEL sel = @selector(closeTab:);
    if([m_delegate respondsToSelector:sel]) {
        [m_delegate performSelector:sel withObject:self];
    }
}

// my solution.. which I need a better name for
#define DELEGATE_TRY_PERFORM_SELECTOR_WITH_SELF(selector_name) \
    do { \
        SEL sel = @selector(selector_name); \
        if([m_delegate respondsToSelector:sel]) { \
            [m_delegate performSelector:sel withObject:self]; \
        } \
    } while(0);


-(void)switchToNextTab:(id)sender {
    DELEGATE_TRY_PERFORM_SELECTOR_WITH_SELF(switchToNextTab:);
}

Answer 1

为什么不在Category上创建UIViewController来为您提供该方法。

首先创建一个.h + .m文件。约定通常是使用您要添加类别的类的名称然后使用+然后使用您想要调用的类。对于这个例子，我会保持简单（UIViewController+additional）

// UIViewController+additional.h
@interface UIViewController (additions)
  - (void)MYsafePerformSelectorOnDelegate:(SEL)selector withObject:(id)anObject;
@end

// UIViewController+additions.m
@implementation UIViewController (additions)

  - (void)MYsafePerformSelectorOnDelegate:(SEL)selector withObject:(id)anObject
  {
    if([m_delegate respondsToSelector:selector]) {
      [m_delegate performSelector:selector withObject:anObject];
    }
  }

@end

然后，您可以将此文件导入到您希望使用此方法的任何位置（或者如果在整个项目中使用它，请考虑.pch）。现在，只要您进入UIViewController子类（已导入UIViewController+additional.h），您就可以调用方法

[self MYsafePerformSelectorOnDelegate:@selector(closeTab:) withObject:self];

注意：通常最好在方法名称前加上类别，以便它们与任何内部方法冲突的可能性更小。

比DELEGATE_TRY_PERFORM_SELECTOR_WITH_SELF更好的名称

1 个答案: