标签：copy UI wait sof ini update top oid sep
| 一、创建多线程的五种方式 |
NSThread * thread=[[NSThread alloc] initWithTarget:self selector:@selector(_update) object:nil];
[NSThread detachNewThreadSelector:@selector(_update) toTarget:self withObject:nil];
[self performSelectorInBackground:@selector(_update) withObject:nil];
NSOperationQueue *queue=[[NSOperationQueue alloc] init];
[queue addOperationWithBlock:^{
for(int i=0;i<50;i++){
printf("子线程\n");
}
}];
//第一步开启线程池
NSOperationQueue * queue=[[NSOperationQueue alloc] init];
//设置并发数目
[queue setMaxConcurrentOperationCount:2];
//第二部创建多线程添加到线程池
NSInvocationOperation * thread1=[[NSInvocationOperation alloc] initWithTarget:self selector:@selector(_update1) object:nil];
NSInvocationOperation *thread2=[[NSInvocationOperation alloc] initWithTarget:self selector:@selector(_update2) object:nil];
[thread1 setQueuePriority:NSOperationQueuePriorityVeryLow];
[thread2 setQueuePriority:NSOperationQueuePriorityVeryHigh];
[queue addOperation:thread1];
[queue addOperation:thread2];
| 二、多线程应用实例，加载图片。 |
考虑到如果加载网络图片会延迟，在一个主线程加载会影响控件的渲染，此时可以采取多线程，异步加载完成后刷新UI。
通过为UIImageView 增加类目来实现多线程下载。
主要代码：
#import "UIImageView+thread.h"
@implementation UIImageView(load)
- (void) setImageWithUrl:(NSString *)url{
[self performSelectorInBackground:@selector(_loadImage:) withObject:url];
}
- (void) _loadImage:(NSString *)u{
@autoreleasepool {
NSURL *url=[NSURL URLWithString:u];
NSData *data=[NSData dataWithContentsOfURL:url];
UIImage *image=[UIImage imageWithData:data];
[self performSelectorOnMainThread:@selector(setImage:) withObject:image waitUntilDone:NO];
}
}
标签：copy UI wait sof ini update top oid sep
原文地址：http://www.cnblogs.com/tangshiguang/p/6753644.html
