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Quiz in "iOS Development" series.

Assume you have images named 'Robot1.png','Robot2.png','Robot3.png','Robot4.png', create an array of UIImage objects called 'robotImages'.

My answer : NSArray * robotImages = [[NSArray:alloc] initWithObjects:[UIImage imageNamed:@"Robot1"],[UIImage imageNamed:@"Robot2"],[UIImage imageNamed:@"Robot3"], [UIImage imageNamed:@"Robot4"],nil];

Sorry, I am a newbie. Can someone explain, wahtI am doing wrong.

Thanks, Nandu

4 Answers

Nathan F.
Nathan F.
30,773 Points

You're missing an important piece of information in your array.

Suppose you also had in your resources these items: 'Robot1.jpg', 'Robot2.jpg','Robot3.jpg','Robot4.jpg'

How would you tell these two sets of items apart? How would you tell the computer which set of resources you wanted?

Thanks Nathan for your reply! Appreciate it !

In the videos they seemed to have skipped the ".png" part of it. So I assumed the same :(

Anyway, I tried adding the .png suffixes as follows. But still I can't get past the quiz :-( :-(

New Answer (with ".png" added): NSArray * robotImages = [[NSArray:alloc] initWithObjects:[UIImage imageNamed:@"Robot1.png"],[UIImage imageNamed:@"Robot2.png"],[UIImage imageNamed:@"Robot3.png"], [UIImage imageNamed:@"Robot4.png"],nil];

It still tells me it i wrong :(

Amit Bijlani
Amit Bijlani
Treehouse Guest Teacher

Your answer is almost right but you have a misplaced colon [NSArray:alloc] it should be [NSArray alloc].

Hi Amit, Thanks ! Thats so silly of me ! Thanks for the videos. I enjoy learning from them. Would be nice if there is a more in depth version of Objective-C tutorials. Thanks !