我正在构建一个项目,我第一次使用线程。图像被覆盖
我采取了一个collectionView我想要显示图像。我在一个数组中获取了10个图像URL。现在,下载后,图像将显示在集合视图中。
但是,当我运行我的项目时,图像即将到来,但图像不断覆盖。
我很困惑如何显示集合视图中的所有图像。
我的代码是
#import "ViewController.h"
@interface ViewController()
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.arrImages = @[@"http://helpyourselfimages.com/wp-content/uploads/2014/10/Nature-Pictures-HD1.jpg",
@"http://helpyourselfimages.com/wp-content/uploads/2014/10/Beautiful-Island-Wallpaper.jpg",
@"http://hdwallpapers4u.eu/wallpaper_3840x2160/booty_hose_sofa_thongs_girl_beautiful_nature_ultra_3840x2160_hd-wallpaper-242177.jpg",
@"http://www.pageresource.com/wallpapers/wallpaper/chelsea-logo-nature-hd-beauty.jpg",
@"http://dowehwall.com/wp-content/uploads/2015/01/hd-wallpaper-beautiful-nature-hd-wallpaper-nature-beautiful-hd-426201-download-this-wallpaper-use-for-facebook-cover-edit-this-wallpapers.jpg",
@"http://imgstocks.com/wp-content/uploads/2013/12/Beautiful-nature-cool-images-background-hd-wallpaper-beautiful-nature.jpg",
@"http://ghost2-gbj.rhcloud.com/content/images/2013/Dec/beautiful_nature_wallpapers_for_desktop_high_definition_wallpaper.jpg",
@"http://www.hdwallpapersos.com/wp-content/uploads/2014/08/nike-air-max-nature-beautiful-pictures.jpg",
@"http://www.3dwallhd.com/wp-content/uploads/2013/02/white_tiger_beautiful-wide.jpg",
@"http://mobiledady.com/wp-content/uploads/2013/04/Beautiful-HD-Nature-Wallpapers-For-Desktop-2013-2014-9.jpg"];
[self fetchData];
}
-(void)fetchData{
dispatch_queue_t imageQueue = dispatch_queue_create("Image Queue",NULL);
for (NSString *urlString in self.arrImages) {
dispatch_async(imageQueue, ^{
NSURL *url = [NSURL URLWithString:urlString];
NSData *imageData = [NSData dataWithContentsOfURL:url];
UIImage *image = [UIImage imageWithData:imageData];
if (!self.imageNature) return;
dispatch_async(dispatch_get_main_queue(), ^{
[self.imageNature setImage:image];
});
});
}
}
-(NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView{
return 1;
}
-(NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section{
return [self.arrImages count];
}
-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
UICollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"collectionCell" forIndexPath:indexPath];
self.imageNature = (UIImageView *)[cell.contentView viewWithTag:1];
return cell;
}
- (IBAction)btnAlrt:(id)sender {
UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"BOOM!!" message:@"Main Thread Is Running" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:nil];
[alert show];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
}
@end
是self.imageNature UIImageView?如果是的话,你将所有的图像设置为相同的UIImageView – Leonardo 2015-03-25 12:59:03
你有什么(除了不正常工作)不是一个好的异步下载模式。看看异步NSURLConnection或像AFNetworking或SDWebImage的库 – 2015-03-25 13:01:01
老兄!我已经理解了你在说什么,但是告诉我如何才能一个接一个地显示集合视图中的所有图像? – iPeter 2015-03-25 13:01:08