Is it possible to substitute body of existing method in UIWebView without subclassing

Question

I am interesting if it possible to substitute the method body of UIWebView in a runtime? I can't subclass UIWebView

For instance, I need to implement:

- (void) paste:(id)sender;
or
- (BOOL) canPerformAction:(SEL)action withSender:(id)sender;

Answer 1

Have you tried out the runtime method method_setImplementation?

Like so:

static IMP originalPaste = NULL;

void myPaste(id rcv, SEL cmd, id sender)
{
    // Your implementation here
}

…
{
    …
    Method m = class_getInstanceMethod([UIWebView class], @selector(paste:));
    originalPaste = method_setImplementation(m, myPaste);
    …
}

Using the originalPaste you can perform a super call within your implementation.