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Vanessa Cantero G贸mez
Vanessa Cantero G贸mez
7,376 Points

Improving the animation task in Crystal Ball App

Hi guys, I have written a better way to load the images.

If you have already made the Animating and Intercepting Events of Cristal Ball App, you saw that you had to write all images names by yourself in viewDidLoad method.

Well, I thought, there's a better (faster) way to do this because all images have a common name: "CB000". So I write this method:

- (void) loadAllBackgroundImages {
    NSString *cbName = @"CB000";
    NSString * imageName;
    NSMutableArray *arrayWithUIImages = [[NSMutableArray alloc] init];

    for (int i = 1; i <61 ; i++) {
        if (i < 10) {
            imageName = [cbName stringByAppendingFormat:@"0%d",i];
        } else {
            imageName = [cbName stringByAppendingFormat:@"%d",i];

        [arrayWithUIImages addObject:[UIImage imageNamed:imageName]];
    self.backgroundImageView.animationImages = arrayWithUIImages;
    self.backgroundImageView.animationDuration = 2.5f;
    self.backgroundImageView.animationRepeatCount = 1;

Then, in viewDidLoad you just have to write

[self loadAllBackgroundImages];

Hope you like it! And If you want to do better (I'm a newbie in objective-c) don't hesitate to do it so I can learn too!

EDIT: Hey, the markdown doesn't work, so I hope you can understand the code! :)

1 Answer

Here's a little trick to pad a positive integer with zeros in front to make it 4-digit long (e.g. 0001, 0032, 0150, 9999):

[NSString stringWithFormat:@"%04d",i];

The formatting string of course works with all other methods/functions including NSLog and stringByAppendingFormat etc.