iOS How is this a Leak?

[Duke Leto]

I have some code that is giving me trouble.

Apparently Instruments tells me that there is a leak in the string:

aNum = round([aSlider value]);
NSString *aString = [[NSString alloc] initWithFormat:@"%1.2f", round(aNum)];
[aText setText:aString];
[aString release];

(aNum, aSlider and aText are properties of the class)
What I do not get is how aString is leaking!

 

[SilentPanda]

I don't see it either. Can you post the output from Instruments?

 

[Duke Leto]

It is a NCSFString, it is 16 bytes, and it has trouble with the line:

[aText setText:[NSString stringWithFormat:@"%1.2f", aNum]];

Beats me!

 

[SilentPanda]

Admittedly I've only still working my way through Objective-C learning (100 more pages!) so I might not have the best insight but...

Are you releasing aText during your dealloc?

Actually I guess you might need to release it in places other than the dealloc... but yeah maybe check that?

 

[Duke Leto]

Yep, in all my classes, all my retained properties are released in the dealloc.

 

[SilentPanda]

Just don't run Instruments anymore... pretend it isn't happening!

 

[Duke Leto]

Then apple wouldn't accept it, would it?

 

[drivefast]

aNum = [B]round[/B]([aSlider value]);
NSString *aString = [[NSString alloc] initWithFormat:@"%1.2f", [B]round[/B](aNum)];

try fixing this first. you may not need round at all, since the printf format will round for you.

 

[Duke Leto]

Got that leak .. but found another interesting one in a drawRect function:

CGContextRef context = UIGraphicsGetCurrentContext();
CGContextClearRect(context, rect);
[fillColor setFill];
CGContextFillEllipseInRect(context, rect);

 

[SilentPanda]

How did you fix the other one?

 

[Duke Leto]

By changing it to:

aNum = [aSlider value];
aNum = round(aNum);

and by getting rid of the second round() call.

 

[Duke Leto]

By the way, is it possible to use Instruments to analyze how the program runs on the phone? There seems to be a problem with the phone because it doesn't have the processing power, and I need Instruments to be able to determine what the process is and how I can stop it.