标签：显示图片 end self tac 并发 nsthread logs struct single
一、队列
1、获取全局的并发队列
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
2、创建一个串行队列
dispatch_queue_t queue = dispatch_queue_create("queueName", NULL);
3、获取主队列
dispatch_queue_t queue = dispatch_get_main_queue();
二、执行函数
1、将任务添加到xx队列中去异步执行
dispatch_async(queue, ^{
NSLog(@"-----下载1---%@", [NSThread currentThread]);
});
2、将任务添加到xx队列中去同步执行
dispatch_sync(queue, ^{
NSLog(@"-----下载2---%@", [NSThread currentThread]);
});
三、线程间的通信
dispatch_async(GlobalQueue, ^{
// 1.子线程下载图片
dispatch_async(MainQueue, ^{
// 2.回到主线程设置图片
});
});
四、延迟执行
1、3秒后回到主线程执行block中的代码
dispatch_queue_t queue = dispatch_get_main_queue();
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(3 * NSEC_PER_SEC)), queue, ^{
NSLog(@"------task------%@", [NSThread currentThread]);
});
2.3秒后自动开启新线程执行block中的代码
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(3 * NSEC_PER_SEC)), queue, ^{
NSLog(@"------task------%@", [NSThread currentThread]);
});
五、一次性执行
+ (instancetype)client
{
static AFNetClient *client = nil;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
client = [[AFNetClient alloc]init];
});
return client;
}
六、队列组的使用
dispatch_group_t group = dispatch_group_create(); dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
dispatch_group_async(group, queue, ^{ // 1.下载图片1
});
dispatch_group_async(group, queue, ^{ // 2.下载图片2 }); // 3.合并图片 (保证执行完组里面的所有任务之后，再执行notify函数里面的block) dispatch_group_notify(group, queue, ^{
// 3.合并图片 (保证执行完组里面的所有任务之后，再执行notify函数里面的block)
dispatch_async(dispatch_get_main_queue(), ^{
// 4.回到主线程显示图片 }); });
七、创建单例
1、工具宏文件HMSingleton.h
// .h文件
#define HMSingletonH(name) + (instancetype)shared##name;
// .m文件
#if __has_feature(objc_arc)
#define HMSingletonM(name) static id _instace; + (id)allocWithZone:(struct _NSZone *)zone { static dispatch_once_t onceToken; dispatch_once(&onceToken, ^{ _instace = [super allocWithZone:zone]; }); return _instace; } + (instancetype)shared##name { static dispatch_once_t onceToken; dispatch_once(&onceToken, ^{ _instace = [[self alloc] init]; }); return _instace; } - (id)copyWithZone:(NSZone *)zone { return _instace; }
#else
#define HMSingletonM(name) static id _instace; + (id)allocWithZone:(struct _NSZone *)zone { static dispatch_once_t onceToken; dispatch_once(&onceToken, ^{ _instace = [super allocWithZone:zone]; }); return _instace; } + (instancetype)shared##name { static dispatch_once_t onceToken; dispatch_once(&onceToken, ^{ _instace = [[self alloc] init]; }); return _instace; } - (id)copyWithZone:(NSZone *)zone { return _instace; } - (oneway void)release { } - (id)retain { return self; } - (NSUInteger)retainCount { return 1;} - (id)autorelease { return self;}
#endif
2、创建单例MHMusicTool
2.1、MHMusicTool.h文件
#import <Foundation/Foundation.h> @interface HMMusicTool : NSObject HMSingletonH(MusicTool) @end
2.2、MHMusicTool.m文件
#import "HMMusicTool.h" @implementation HMMusicTool HMSingletonM(MusicTool) @end
3、使用单例MHMusicTool
HMMusicTool *tool1 = [HMMusicTool sharedMusicTool]; HMMusicTool *tool2 = [HMMusicTool sharedMusicTool];
标签：显示图片 end self tac 并发 nsthread logs struct single
原文地址：http://www.cnblogs.com/cchHers/p/6741252.html
