適用於iOS的幻燈片放映圖像

Question

我的照片有幻燈片文件的m文件，我有8張，但是運行該程序時，它會跳過第一張圖片，並從第二張圖片開始。

- (void)viewDidLoad
{    
    [super viewDidLoad];   
    imageId=0;
    [NSTimer scheduledTimerWithTimeInterval:2.0 target:self selector:@selector(changeImage) userInfo:nil repeats:YES];
}

-(void)changeImage
{
    imageId = imageId + 1;
    CATransition * trs = [CATransition animation];
    trs.duration = 1;
    [trs setType:kCATransitionPush];
    int id = imageId % NUMBER_OF_IMAGES;
    imageView.image = [UIImage imageNamed:[NSString stringWithFormat:@"%d.png", id]];
    [imageView.layer addAnimation:trs forKey:kCATransition];
}

Answer 1

就像克里斯說的那樣，當您加載圖像時，您正在增加圖像編號。 只需將增量線移動到方法的末尾即可：

-(void)changeImage {
//    imageId = imageId + 1;
    CATransition * trs = [CATransition animation];
    trs.duration = 1;
    [trs setType:kCATransitionPush];
    int id = imageId % NUMBER_OF_IMAGES;
    imageView.image = [UIImage imageNamed:[NSString stringWithFormat:@"%d.png", id]];
    [imageView.layer addAnimation:trs forKey:kCATransition];
    imageId++;
}