This question was originally asked for the objective-c programming language. At the time of writing, swift didn't even exist yet.
Is it possible to change only one property of a CGRect
?
For example:
self.frame.size.width = 50;
instead of
self.frame = CGRectMake(self.frame.origin.x,
self.frame.origin.y,
self.frame.size.width,
50);
of course I understand that self.frame.size.width
is read only so I'm wondering how to do this?
CSS ANALOGY proceed at your own risk
for those of you who are familiar with CSS
, the idea is very similar to using:
margin-left: 2px;
instead of having to change the whole value:
margin: 5px 5px 5px 2px;
To answer your original question: yes, it's possible to change just one member of a CGRect
structure. This code throws no errors:
myRect.size.width = 50;
What is not possible, however, is to change a single member of a CGRect
that is itself a property of another object. In that very common case, you would have to use a temporary local variable:
CGRect frameRect = self.frame;
frameRect.size.width = 50;
self.frame = frameRect;
The reason for this is that using the property accessor self.frame = ...
is equivalent to [self setFrame:...]
and this accessor always expects an entire CGRect
. Mixing C-style struct
access with Objective-C property dot notation does not work well in this case.