线程间通信的三种方式(NSThread,GCD,NSOperation)

一.NSThread线程间通信

#import "ViewController.h"

@interface ViewController ()<UIScrollViewDelegate>

@property (strong, nonatomic) IBOutlet UIScrollView *scrollView;

@property (weak, nonatomic)  UIImageView *imageView;

@end

@implementation ViewController

- (void)viewDidLoad {

[super viewDidLoad];

//1.创建我们的UIImageView

[self createUIImageView];

//2.去网络上下载图片

NSString *URLString = @"http://e.hiphotos.bdimg.com/album/pic/item/9345d688d43f8794f0ab07ddd01b0ef41ad53ae8.jpg";

[self performSelectorInBackground:@selector(loadImage:) withObject:URLString];

//3.设置最大最小缩放比例

self.scrollView.maximumZoomScale  = 2.0;

self.scrollView.minimumZoomScale  = 0.5;

}

/**

去子线程下载图片

*/

- (void)loadImage:(NSString *)URLString{

NSLog(@"---loadImage start---");

//1.生成NSURL

NSURL *url = [NSURL URLWithString:URLString];

//2.去网络上下载,网络上传输的都是一堆01010的二进制

NSData *imageData = [NSData dataWithContentsOfURL:url];

//3.将我们的imageData转成我们UIImage

UIImage *image = [UIImage imageWithData:imageData];

/**

waitUntilDone 等我们的updateUI 方法执行完毕之后,再执行后面的

*/

[self performSelectorOnMainThread:@selector(updateUI:) withObject:image waitUntilDone:NO];

NSLog(@"---loadImage end---");

}

- (void)updateUI:(UIImage *)image{

//1.将image设置给imageView

self.imageView.image = image;

//2.根据我们的图片大小,来决定我们UIImageView的尺寸

[self.imageView sizeToFit];

//3.设置scrollView的contentSize

self.scrollView.contentSize = image.size;

NSLog(@"update UI end");

}

- (void)createUIImageView{

UIImageView *imageView =[[UIImageView alloc] init];

[self.scrollView addSubview:imageView];

self.imageView = imageView;

}

#pragma mark - scrollViewDelegate

- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView{

return self.imageView;

}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{

NSLog(@"%s",__func__);

}

@end

二.GCD线程间通信

#import "ViewController.h"

@interface ViewController ()<UIScrollViewDelegate>

@property (strong, nonatomic) IBOutlet UIScrollView *scrollView;

@property (weak, nonatomic)  UIImageView *imageView;

@end

@implementation ViewController

- (void)viewDidLoad {

[super viewDidLoad];

//1.创建我们的UIImageView

[self createUIImageView];

//2.去网络上下载图片

/**

去子线程,并发,全局,串行         方法:异步

两个参数

参数1:队列

参数2:任务

*/

dispatch_async(dispatch_get_global_queue(0, 0), ^{

NSLog(@"loadImage----%@",[NSThread currentThread]);

//0.URLString

NSString *URLString = @"http://e.hiphotos.bdimg.com/album/pic/item/9345d688d43f8794f0ab07ddd01b0ef41ad53ae8.jpg";

//1.生成NSURL

NSURL *url = [NSURL URLWithString:URLString];

//2.去网络上下载,网络上传输的都是一堆01010的二进制

NSData *imageData = [NSData dataWithContentsOfURL:url];

//3.将我们的imageData转成我们UIImage

UIImage *image = [UIImage imageWithData:imageData];

//去主线程更新UI

dispatch_async(dispatch_get_main_queue(), ^{

NSLog(@"---updateUI---%@",[NSThread currentThread]);

//1.将image设置给imageView

self.imageView.image = image;

//2.根据我们的图片大小,来决定我们UIImageView的尺寸

[self.imageView sizeToFit];

//3.设置scrollView的contentSize

self.scrollView.contentSize = image.size;

});

});

//3.设置最大最小缩放比例

self.scrollView.maximumZoomScale  = 2.0;

self.scrollView.minimumZoomScale  = 0.5;

}

- (void)createUIImageView{

//1.创建imageView

UIImageView *imageView =[[UIImageView alloc] init];

[self.scrollView addSubview:imageView];

self.imageView = imageView;

}

#pragma mark - scrollViewDelegate

- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView{

return self.imageView;

}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{

NSLog(@"%s",__func__);

}

@end

三.NSOperation线程间通信

#import "ViewController.h"

@interface ViewController ()<UIScrollViewDelegate>

@property (strong, nonatomic) IBOutlet UIScrollView *scrollView;

@property (weak, nonatomic)  UIImageView *imageView;

@end

@implementation ViewController

- (void)viewDidLoad {

[super viewDidLoad];

//1j.创建我们的UIImageView

[self createUIImageView];

//2.去网络上下载图片

//先去子线程做耗时操作(下载)  然后再去主线程更新UI

//创建并发队列

NSOperationQueue  *queue = [[NSOperationQueue alloc] init];

[queue addOperationWithBlock:^{

//子线程

NSLog(@"loadImage----%@",[NSThread currentThread]);

//0.URLString

NSString *URLString = @"http://e.hiphotos.bdimg.com/album/pic/item/9345d688d43f8794f0ab07ddd01b0ef41ad53ae8.jpg";

//1.生成NSURL

NSURL *url = [NSURL URLWithString:URLString];

//2.去网络上下载,网络上传输的都是一堆01010的二进制

NSData *imageData = [NSData dataWithContentsOfURL:url];

//3.将我们的imageData转成我们UIImage

UIImage *image = [UIImage imageWithData:imageData];

//去主线程更新UI

[[NSOperationQueue mainQueue] addOperationWithBlock:^{

//主线程

NSLog(@"---updateUI---%@",[NSThread currentThread]);

//1.将image设置给imageView

self.imageView.image = image;

//2.根据我们的图片大小,来决定我们UIImageView的尺寸

[self.imageView sizeToFit];

//3.设置scrollView的contentSize

self.scrollView.contentSize = image.size;

}];

}];

//3.设置最大最小缩放比例

self.scrollView.maximumZoomScale  = 2.0;

self.scrollView.minimumZoomScale  = 0.5;

}

- (void)createUIImageView{

UIImageView *imageView =[[UIImageView alloc] init];

[self.scrollView addSubview:imageView];

self.imageView = imageView;

}

#pragma mark - scrollViewDelegate

- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView{

return self.imageView;

}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{

NSLog(@"%s",__func__);

}

@end