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iOS Build a Simple iPhone App (iOS7) Animating and Intercepting Events Image Based Animation

Posted by Rodrigo Gruber
Rodrigo Gruber
1,235 Points

Not animating

ViewController.h: www.pastebin.com/ddW8ETj8 ViewController.m: www.pastebin.com/XMWLXs5w

Both CrystalBall Class files are working correctly (CrystalBall.h/CrystalBall.m) and are not related to this problem, the point is: The program compiles and runs on the simulator just fine, but when I click or shake it; it doesn't animate. It only changes the text. Do you guys know what I might have done wrong?

Oh, and the Main.storyboard background is linked to it alright. (Referencing outlets, right?)

Marshall Huss
Marshall Huss
3,504 Points

Put a breakpoint in -makePrediction and see if it ever makes it to the method. Does it?

3 Answers

Rodrigo Gruber
Rodrigo Gruber
1,235 Points
Rodrigo Gruber
Rodrigo Gruber
1,235 Points

Thanks for your reply +Marshall Huss, and how do I exactly do that?

Marshall Huss
Marshall Huss
3,504 Points

See Apple's guide on breakpoints.

Rodrigo Gruber
Rodrigo Gruber
1,235 Points
Rodrigo Gruber
Rodrigo Gruber
1,235 Points

It does, together with it I used a NSLog(@"It works"); on the method implementation of makePrediction and it does work too.

The problem seems to be something related to the Main.storyboard and the animation framework itself I guess.

Marshall Huss
Marshall Huss
3,504 Points

OK, make sure your UIImageView outlet is tied up correctly. To confirm, break in the -makePrediction method. When it stop you'll see the bottom of the screen pop up with variables on the left and console on the right.

Either expand self and make sure backgroundImageView is not nil. Alternatively you can type po self.backgroundImageView in the console.

Rodrigo Gruber
Rodrigo Gruber
1,235 Points
Rodrigo Gruber
Rodrigo Gruber
1,235 Points

The self (using the breakpoint) refers to this variables: UIVIewController, _predictionLabel,_crystalBal, and_backgroundImageView. On the self _backgroundImageView the storage option shows only a "[0]", I guess that's what you mean by a nil?

Marshall Huss
Marshall Huss
3,504 Points

I'm afraid I can't help anymore unless I see the project. If you want to zip up the project and share a link I will take a look.