从互联网同时加载各种图像objective-c

Question

我试图在同一时间加载5个图像，因为它们将它放在视图上并每5秒更改一次图像（在当前5之间更改） 我创建一个在viewDidLoad中并启动定时器当前类至极被调用时，加载所有图像的方法是这样的：

-(NSMutableArray *)getAllPhotos 
{ 
    NSMutableArray * photosArray = [[NSMutableArray alloc]init]; 

    NSString * pic0 = [NSString stringWithFormat:@"http://74.53.32.202/~ltashiro/public/Servidor/Images/0.png"]; 
    NSString * pic1 = [NSString stringWithFormat:@"http://74.53.32.202/~ltashiro/public/Servidor/Images/1.png"]; 
    NSString * pic2 = [NSString stringWithFormat:@"http://74.53.32.202/~ltashiro/public/Servidor/Images/2.png"]; 
    NSString * pic3 = [NSString stringWithFormat:@"http://74.53.32.202/~ltashiro/public/Servidor/Images/3.png"]; 

    NSURL *image0 = [NSURL URLWithString:pic0]; 
    NSURL * image1 = [NSURL URLWithString:pic1]; 
    NSURL * image2 = [NSURL URLWithString:pic2]; 
    NSURL * image3 = [NSURL URLWithString:pic3]; 

    NSMutableArray * arrayURL = [[NSMutableArray alloc]init]; 
    [arrayURL addObject:image0]; 
    [arrayURL addObject:image1]; 
    [arrayURL addObject:image2]; 
    [arrayURL addObject:image3]; 

    for (int i = 0; i<4; i++) 
    { 
     NSData * imageData = [[NSData alloc]initWithContentsOfURL:[arrayURL objectAtIndex:i]]; 
     Photo * aPhoto = [[Photo alloc]init]; 
     aPhoto.photoID = (i+1); 
     aPhoto.photo = [[UIImage alloc]initWithData:imageData]; 

     [photosArray addObject:aPhoto]; 
     [aPhoto release]; 
     [imageData release]; 
    } 

    return photosArray; 
} 

但有时上推出的appcrashs，那里有没有其他解决办法abordation呢？

Answer 1

我在寻找这里发布的问题。我在这里找到了一个解决方案： http://www.switchonthecode.com/tutorials/loading-images-asynchronously-on-iphone-using-nsinvocationoperation

虽然没有测试过。