如何覆盖框架类中的方法(运行时) [英] How to override a method in framework's class (runtime)

问题描述

问题:
高于上述条件时，框架将缓存图像数据:

problem:
framework will cache the image data when above:

[UIImage imageNamed:]

我不希望缓存发生，所以我可以用

I don't want the caching happen,so I can replace it by

[UIImage imageOfContentOfFile:]

似乎解决了，但是在我的测试中，在xib的实例化进度中，框架使用了 imageNamed:而不是 imageOfContentOfFile .
也就是说，xib加载的图像仍被缓存.

Seems solved,but after my tests,in xib's instantiate progress, framework uses imageNamed: rather than imageOfContentOfFile.
That is, images loaded by xib still cached.

因此，我尝试覆盖UIImage的imageNamed:方法，使所有此方法都不要缓存.

So I try to override the UIImage's imageNamed: method, make all this method DO NOT CACHE.

-尝试1.类别:

@implementation UIImage (ImageNamedNoCache)

+ (UIImage *)imageNamed:(NSString *)name; 
{
    NSString* path = [[NSBundle mainBundle] pathForResource:name ofType:nil];
    return [UIImage imageWithContentsOfFile:path];
}

@end

-result:warning.类别正在实现一种方法，该方法也将由其主类实现".

--result:warning."Category is implementing a method which will also be implemented by its primary class"

-尝试2.运行时替换方法的imp

    //get super method
Method method_imageNamed = class_getClassMethod([UIImage class], @selector(imageNamed:));

//get my method
Method method_myImageNamed = class_getClassMethod([self class], @selector(myImageNamed:));

//get my imp
IMP imp_myImageNamed = method_getImplementation(method_myImageNamed);

//set super method's imp to my imp
method_setImplementation(method_imageNamed, imp_myImageNamed);

-结果这些也只能尝试在我调用 [UIImage imageNamed:]
时起作用但是xib的实例化不起作用.

--result these too try only work when I invoke [UIImage imageNamed:]
but xib's instantiation doesn't work.

帮助我，谢谢

推荐答案

听起来像方法陷入困境.我觉得这很危险，也没有必要，但是如果您愿意的话，它是一个选择.使用风险自负.

Sounds like a job for method swizzling. I find it dangerous and unnecessary, but if you are so inclined, it is an option. Use at your own risk.

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