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iOS Object-Oriented Objective-C Memory, Arrays and Loops, Oh My! Review Dictionaries and Arrays

Posted by jozsefgyongyosi
jozsefgyongyosi
638 Points

Did we have to use new/not yet learned methods to solve the 3rd exercise?

I was stucked for some time at the 3rd exercise and i found a solution to it on another forum. I might have forgotten the lesson where we learned the initWithObjectsAndKeys or setObject: forKey: methods.

  So my question is: if these methods weren't taught yet how to resolve this exercise?
variable_assignment.mm 
NSArray *shoeOrder = @[ @"Charles Smith", @(9.5), @"loafer", @"brown"];
NSMutableDictionary *shoeOrderDict = [[NSMutableDictionary alloc] initWithObjectsAndKeys: @"customer", @"size", @"style", @"color", nil];

[shoeOrderDict setObject:[shoeOrder objectAtIndex:0] forKey:@"customer"];
[shoeOrderDict setObject:[shoeOrder objectAtIndex:1] forKey:@"size"];
[shoeOrderDict setObject:[shoeOrder objectAtIndex:2] forKey:@"style"];
[shoeOrderDict setObject:[shoeOrder objectAtIndex:3] forKey:@"color"];

1 Answer

Philip Gales
Philip Gales
15,193 Points

The last challenge is typically testing your knowledge of the whole series. I do agree with you, they are often difficult as you have learned a lot. I highly recommend you take breaks and practice playing with the code after every video.

All the methods appear to be taught in the previous series in the video titled "NSDictionary and NSMutableDictionary cont.".

jozsefgyongyosi
jozsefgyongyosi
638 Points

Thanks for the answer and for the advice.