使用NSThread实现线程间的通信
#import "ViewController.h"
@interface ViewController ()
@property (weak, nonatomic) IBOutlet UIImageView *imageView;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
- (void)download {
// 1.图片地址
NSString *urlStr = @"http://image1.mop.com/images/project14/2012-10-19/13506138571471411.jpg";
NSURL *imageUrl = [NSURL URLWithString:urlStr];
// 2.根据图片的地址下载图片的二进制数据
NSData *imageData = [NSData dataWithContentsOfURL:imageUrl];
// 3.设置图片
UIImage *image = [UIImage imageWithData:imageData];
// 4.回到主线程，刷新UI界面
[self.imageView performSelectorOnMainThread:@selector(setImage:) withObject:image waitUntilDone:YES];
NSLog(@"download --- %@", [NSThread currentThread]);
}
- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event {
[self performSelectorInBackground:@selector(download) withObject:nil];
}
@end
实现效果
实现效果.png
⚠️注意！！！
如果点击屏幕发现不能正常下载图片，并且报以下错误的话
App Transport Security has blocked a cleartext HTTP (http://) resource load since it is insecure. Temporary exceptions can be configured via your app's Info.plist file.
说明你没有允许网络服务，还需要在info.plist文件中增加如下设置
打开网络服务.png
