Objective-C subclass rewrite method call [Super method] Small Experiment

Recent review of learn objective-C on the Mac

In Chapter 4th, [Super setfillcolor: C] is called for rewriting. It may be because the translation logic is unclear. I wrote a small example to understand it.

Define a father class and son class

Father:

#import <Foundation/Foundation.h>@interface father : NSObject{    int num;}-(void)setNum:(int)num;@end

#import "father.h"@implementation father-(void)setNum:(int)c{    num = c;    NSLog(@"i am father");}@end

Son:

#import <Foundation/Foundation.h>#import "father.h"@interface son : father-(void)setNum:(int)num;@end

# Import "son. H "@ implementation son-(void) setnum :( INT) c {num = C; if (1 = num) {nslog (@" I am Son ");} [Super setnum: C]; // The key here} @ end

Main:

#import <Foundation/Foundation.h>#import "son.h"int main(int argc, const char * argv[]){    @autoreleasepool {        son *ii = [[son alloc]init];        [ii setNum:1];    }    return 0;}

Output result:

2014-08-06 11:00:35.731 testtest[13606:303] i am son2014-08-06 11:00:35.732 testtest[13606:303] i am father

If [Super setnum: C] is removed, only I am son is output. Obviously, the subclass rewrite method adds its own features, while the [Super method] is used to retain the features of the parent class.