Use variables from +(void)initialize in other functions

Question

So I have the following initialize method :

+(void)initialize 
{
    static BOOL init = NO 
    if init == NO
        {
            NSDictionary *dict = @{NSFontAttributeName......};
            init = YES;
        }
}

Now, I have a method say - drawer which requires dict

-(void) drawer:(CGRect)rect 
{
    [self.string drawInRect:CGRect........... withAttributes:dict];
}

When I call the dict in drawer, Xcode says - "Use of undeclared identifier dict. Why does this happen? Can someone help me out here? How do I get this method to access dict?

What's the point of the `init` variable? `initialize` is only called once per class. — rmaddy, Feb 25 '14 at 03:15
@rmaddy: I have actually burned myself with that assumption before. If your class is involved in key-value observing, `+initialize` can actually be called twice: once in your class (for example, `VSGame`), and a second time in the private KVO class (`NSKVONotifying_VSGame`). So, depending on what you're doing in that method, you may want to take those kind of precautions... — NSGod, Feb 25 '14 at 18:39

score 2 · Accepted Answer · answered Feb 25 '14 at 02:00

2

As you may know, dict in +(void)initialize is local variable of that function. Therefore, in -(void)drawer: you can't access dict since it isn't in same scope.

If you want to use dict as global variable accessible anywhere, Declare it out of the function scope.

answered Feb 25 '14 at 02:00

Kyokook Hwang

2,682
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Best to declare it as a file-scoped variable, using `static`, rather than global. – jscs Feb 25 '14 at 02:04
@JoshCaswell Yes. That's my favorite way to avoid clashes of symbols. – Kyokook Hwang Feb 25 '14 at 02:09

Use variables from +(void)initialize in other functions

1 Answers1