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iOS Objective-C Basics (Retired) Introduction to Objective-C From Structs to Objects

John Saunders
John Saunders
288 Points
Posted by John Saunders
John Saunders
288 Points

Repeating declarations more than once in code.

In the code below, why is _radius = radius; initialized twice? Once at the top and once at the bottom.

import "Sphere.h"

@implementation Sphere

-(void)setRadius:(float)radius { _radius = radius; }

-(float)radius { return _radius; }

-(void)setCenter:(NSArray *)center {

_center = center;

}

-(NSArray *)center { return _center; }

-(void)setCenter:(NSArray *)center radius:(float)radius { _center = center; _radius = radius;

} @end

1 Answer

J Andrew Scott
J Andrew Scott
30,626 Points
J Andrew Scott
J Andrew Scott
30,626 Points

That last method looks like a convenience method for setting the center and radius in one go, rather than calling setRadius: and setCenter: separately. The code looks valid as-is but it would be better practice to do something like this:

- (void)setCenter:(NSArray *)center radius:(float)radius {
    [self setCenter:center];
    [self setRadius:radius];
}