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objective c - Difference between setting a property directly and using its setter?

What is the difference between these two?

  • self.view.color = [UIColor redColor];
  • [self.view setColor:[UIColor redColor]];
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Nothing.

  • With self.view.color = ... the property's setter in called implicitly.
  • With [self.view setColor:...] you call the setter explicitly.

More in detail: UIView has a color property something like:

@property (nonatomic, strong) UIColor* color;

In Objective-C this automatically defines an underlying ivar _color, and generates code for the setter and getter. (What code is generated depends on the modifiers nonatomic, ... you specify.)

When you type self.view.color = ... the compiler sees that your color is a property, and internally replaces it with [self.view setColor:...].


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