What makes a dollar the $ height of a UITextfield object?

Question

I just found out that there are some properties on class objects that have a dollar sign as a prefix:

$height
$left
$origin
$size

... etc.

I can use it as a setter, for example.

self.textField.$height = 44;

Q: what is it called, what is it useful for, and is it good to use?

Answer 1

It seems that you are using the UIView + FrameAdditions.h category .

More about categories here .

Signs

$ doesn't really matter much in this case - they are actually a bit unconventional for use in ObjC.

This is the way that the developer called helper methods in this category.

$-prefix , , , ObjC UIView frame category helper.

( ) " jQuery UIViews"

: ?

: $- - , . , , - .

.