How to use this macro

Question

Hello everyone i have these defined in my .pch

#define HIDE_TABBAR
#define SHOW_TABBAR

#define IS_IPHONE_5 ( fabs( ( double )[ [ UIScreen mainScreen ] bounds ].size.height - ( double )568 ) < DBL_EPSILON )

And

#if IS_IPHONE_5
HIDE_TABBAR=568 
#else
HIDE_TABBAR=480 
#endif

#if IS_IPHONE_5
SHOW_TABBAR=519
#else
SHOW_TABBAR=431
#endif

Basically what i want to do is to check if screen is iphone 5 , and depending screen size set the define variables and use it in .m code. Can you tell me how i can achieve this?

Muruganandham K · Answer 1 · 2014-02-11T12:55:47.727

2

Do like this

   if(IS_IPHONE_5)
    {
      // for iphone 5
    }
    else
    {
        // for non iphone 5
    }

EDIT: (wrt: avoid using if/else in my code) use Ternary operation

edited Feb 11 '14 at 12:55

answered Feb 11 '14 at 12:14

Muruganandham K

5,271
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1

Best to explain why the current code doesn't work – Wain Feb 11 '14 at 12:15
Hello i am want to use HIDE_TABBAR in .m instead. I am trying to avoid using if/else in my code .. – veereev Feb 11 '14 at 12:17
3

@veereef No if elses in your code? :P Are you mad? – Sulthan Feb 11 '14 at 12:20
i meant in my .m file IF(is_iphone5) – veereev Feb 11 '14 at 12:23
1

Don't you want it to change at run-time? Then you can have one App for both platforms?! I would make a helper class where I got all the system specific information at run-time. – AnthonyLambert Feb 11 '14 at 12:35
1

Isn't this going to break anyway? surely these values change when you run your application and there is a call in progress etc... – AnthonyLambert Feb 11 '14 at 12:38

Paul R · Accepted Answer · 2014-02-11T12:25:43.983

1

Like this:

const int HIDE_TABBAR = IS_IPHONE_5 ? 568 : 480;
const int SHOW_TABBAR = IS_IPHONE_5 ? 519 : 431;

or even:

const int HIDE_TABBAR = IS_IPHONE_5 ? 568 : 480;
const int SHOW_TABBAR = HIDE_TABBAR - 49;

If you really have to use macros for this (which is bad programming, but hey, it's your app):

#define HIDE_TABBAR (IS_IPHONE_5 ? 568 : 480)
#define SHOW_TABBAR (HIDE_TABBAR - 49)

edited Feb 11 '14 at 12:25

answered Feb 11 '14 at 12:19

Paul R

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hello thanks but this can't be written in prefix.pch, i have to add it in .m file? right? – veereev Feb 11 '14 at 12:22

How to use this macro

2 Answers2