Overriding a variadic method in objective-c
When subclassing in objective-c, how can I forward a call to the superclass in the case of a variadic method. By what should I replace the ??? below to send all the objects I got?
- (void) appendObjects:(id) firstObject, ...
{
[super appendObjects: ???开发者_如何学C];
}
You can't. To safely pass all the variadic arguments, you need a method to accept a va_list
.
In super,
-(void)appendObjectsWithArguments:(va_list)vl {
...
}
-(void)appendObject:(id)firstObject, ...
va_list vl;
va_start(vl, firstObject);
[self appendObjectsWithArguments:vl];
va_end(vl);
}
And use [super appendObjectsWithArguments:vl]
when you override the method in the subclass.
Try this:
- (void) appendObjects:(id) firstObject, ...
{
va_list args = &firstObject;
[super appendObjects: args];
}
If that doesn't do the trick, read the manual pages on varargs.
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