Objective-C dynamically created methods and compiler warnings

问题

If I generate methods dynamically on runtime and then call them - how can I convince compiler that the class will respond to undeclared (generated) methods and make it not throw warnings?

Update in regard to answers

When I generate the methods - their name is not known at compile time. To give an example - if I have a view controller MyFooController and it's initiated with method initWithFoo:(Foo*)foo, I'd be able to generate method like pushMyFooControllerWithFoo:(Foo *)foo for UINavigationController. Hence you notice that declaring such methods would be counter-productive.

回答1:

This doesn't directly answer your question, but if I was generating method names (presumably from strings), I would call them using the string names, hence bypassing the compiler warnings.

[fooController performSelector:NSSelectorFromString(@"pushMyFooControllerWithFoo:") withObject:foo];

That way you are responsible for the validity of the generated method names.

回答2:

Since you are adding methods on runtime, so you should also invoke them with runtime function, objc_msgSend or performSelector:withObject:for example, so the compiler will not going to warn you anything.

回答3:

Well, if you call them, you know their signature, and if you know their signature, you can declare them, can't you?

回答4:

Declare this method in a category for NSObject and make an empty implementation:

@interface NSObject (DynamicMethodsCategory)

- (void)doSomething;

@end

@implementation NSObject (DynamicMethodsCategory)

- (void)doSomething
{
}

@end

In your object you can call it without any warnings:

@implementation MyObject

- (void)someMethod
{
    [self doSomething];
}

@end

Then generate implementation of [MyObject doSomething] dynamically, it will be called instead of NSObject's one.

Update: Alternatively, the method can be declared in a category for the object. This suppresses the compiler's Incomplete implementation warning. However, I think this is not a good workaround, because the application will crash if the method is not created dynamically in runtime before it is called.

来源：https://stackoverflow.com/questions/7702318/objective-c-dynamically-created-methods-and-compiler-warnings