//  DYFViewController.m//  624-03-NSOperation////  Created by dyf on 14-6-24.//  Copyright (c) 2014年 ___FULLUSERNAME___. All rights reserved.//#import "DYFViewController.h"@interface DYFViewController ()@end@implementation DYFViewController- (void)viewDidLoad{    [super viewDidLoad];	// Do any additional setup after loading the view, typically from a nib.          [self testOperationQueue];}- (void)testOperationListen {    NSBlockOperation *operation3 = [NSBlockOperation blockOperationWithBlock:^{        NSLog(@"下载图片1111111%@", [NSThread currentThread]);        // 下载图片    }];    operation3.completionBlock = ^{        // 下载完图片后想做的时期    };    // 2.创建队列    NSOperationQueue *queue = [[NSOperationQueue alloc] init];    [queue addOperation:operation3];}- (void)testOperationQueue {    // 1.封装操作    NSInvocationOperation *operation1 = [[NSInvocationOperation alloc] initWithTarget:self selector:@selector(download) object:nil];    NSInvocationOperation *operation2 = [[NSInvocationOperation alloc] initWithTarget:self selector:@selector(run) object:nil];        NSBlockOperation *operation3 = [NSBlockOperation blockOperationWithBlock:^{        NSLog(@"1111111%@", [NSThread currentThread]);    }];        [operation3 addExecutionBlock:^{        NSLog(@"222222%@", [NSThread currentThread]);    }];    [operation3 addExecutionBlock:^{        NSLog(@"33333%@", [NSThread currentThread]);    }];    // 2.创建队列    NSOperationQueue *queue = [[NSOperationQueue alloc] init];    // 5以内，2~3为宜    queue.maxConcurrentOperationCount = 2;#warning 面试题    // 设置操作依赖(一定要在添加到队列中前设置)    [operation2 addDependency:operation1]; // 执行顺序取决于依赖，先执行完operation1再执行operation2// 注意：不能相互依赖，循环操作        // 3.添加操作到队列中（自动执行操作，自动开启线程）    [queue addOperation:operation1];    [queue addOperation:operation2];    [queue addOperation:operation3];        // 取消所有线程    //[queue cancelAllOperations];        // 暂停队列    //[queue setSuspended:YES];        // 设置操作优先级    //operation1.queuePriority = NSOperationQueuePriorityVeryHigh;        }- (void)testNSBlockOperation {    // 1.创建操作对象，封装要执行的任务    NSBlockOperation *operation = [NSBlockOperation blockOperationWithBlock:^{        for (int i = 0; i < 11; i++) {            NSLog(@"1111111%@", [NSThread currentThread]);        }    }];    // 任务数在2各以上，就会开线程    [operation addExecutionBlock:^{        for (int i = 0; i < 11; i++) {            NSLog(@"222222%@", [NSThread currentThread]);        }    }];    [operation addExecutionBlock:^{        for (int i = 0; i < 11; i++) {            NSLog(@"33333%@", [NSThread currentThread]);        }    }];    // 2.执行操作    [operation start];}- (void)testNSInvocationOperation {    // 1.创建操作对象，封装要执行的任务    NSInvocationOperation *operation = [[NSInvocationOperation alloc] initWithTarget:self selector:@selector(download) object:nil];    // 2.执行操作(默认情况下，若操作没有放到队列queue中，都是同步执行)    [operation start];}- (void)download{    for (int i = 0; i < 11; i++) {        NSLog(@"download-----%@", [NSThread currentThread]);    }}- (void)run{    for (int i = 0; i < 11; i++) {        NSLog(@"run------%@", [NSThread currentThread]);    }}@end

////  DYFDownloadOperation.h//  624-05-自定义Operation////  Created by dyf on 14-6-24.//  Copyright (c) 2014年 dyf. All rights reserved.//#import <Foundation/Foundation.h>@class DYFDownloadOperation;@protocol DYFDownloadOperationDelegate <NSObject>@optional- (void)downloadOperation:(DYFDownloadOperation *)operation didFinishedDownload:(UIImage *)image;@end@interface DYFDownloadOperation : NSOperation@property (nonatomic, copy) NSString *url;@property (nonatomic, strong) NSIndexPath *indexPath;@property (nonatomic, weak) id<DYFDownloadOperationDelegate> delegate;@end

////  DYFDownloadOperation.m//  624-05-自定义Operation////  Created by dyf on 14-6-24.//  Copyright (c) 2014年 dyf. All rights reserved.//#import "DYFDownloadOperation.h"@implementation DYFDownloadOperation/** *  在main方法中实现具体操作 */- (void)main{    @autoreleasepool {        if (self.isCancelled) return;        NSURL *imaUrl = [NSURL URLWithString:self.url];        if (self.isCancelled) return;        // 下面这行很耗时        NSData *data = [NSData dataWithContentsOfURL:imaUrl];        if (self.isCancelled) return;        UIImage *image = [UIImage imageWithData:data];        if (self.isCancelled) return;                // 返回主线程显示图片        // 通过代理        if ([self.delegate respondsToSelector:@selector(downloadOperation:didFinishedDownload:)]) {            [self.delegate downloadOperation:self didFinishedDownload:image];        }    }}@end

////  DYFTableViewController.m//  624-05-自定义Operation////  Created by dyf on 14-6-24.//  Copyright (c) 2014年 ___FULLUSERNAME___. All rights reserved.//#import "DYFTableViewController.h"#import "DYFAppModel.h"#import "DYFDownloadOperation.h"#warning Dictionary基础知识不太理解，字典的赋值回去看看笔记@interface DYFTableViewController ()<DYFDownloadOperationDelegate>@property (nonatomic, strong) NSArray *apps;@property (nonatomic, strong) NSOperationQueue *queue;/** *  key:url   value:operation对象 */@property (nonatomic, strong) NSMutableDictionary *oprations;/** *  key:url   value:image对象 */@property (nonatomic, strong) NSMutableDictionary *images;@end@implementation DYFTableViewController#pragma mark - 4个懒加载- (NSArray *)apps{    if (!_apps) {        NSString *path = [[NSBundle mainBundle] pathForResource:@"apps" ofType:@"plist"];        NSArray *arrayApps = [NSArray arrayWithContentsOfFile:path];                NSMutableArray *arrayM = [NSMutableArray arrayWithCapacity:arrayApps.count];        for (NSDictionary *dict in arrayApps) {            DYFAppModel *appM = [DYFAppModel appWithDict:dict];            [arrayM addObject:appM];        }        _apps = arrayM;    }    return _apps;}- (NSOperationQueue *)queue{    if (!_queue) {        _queue = [[NSOperationQueue alloc] init];        // 设置最大并发线程数，最多同时下载3张图片        _queue.maxConcurrentOperationCount = 3;    }    return _queue;}- (NSMutableDictionary *)oprations{    if (!_oprations) {        _oprations = [[NSMutableDictionary alloc] init];    }    return _oprations;}- (NSMutableDictionary *)images{    if (!_images) {        _images = [NSMutableDictionary dictionary];    }    return _images;}- (void)viewDidLoad{    [super viewDidLoad];	// Do any additional setup after loading the view, typically from a nib.}#pragma mark - 数据源方法- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{    return self.apps.count;}- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{    // 1.创建cell    static NSString *identifier = @"apps";    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:identifier];    if (!cell) {        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:identifier];    }    // 2.设置cell的数据    DYFAppModel *app = self.apps[indexPath.row];    cell.textLabel.text = app.name;    cell.detailTextLabel.text = app.download;        // 重点是如何从网络下载图片传入cell上面    // 每个url对应一个DYFDownloadOperation对象    // 每个url对应一个image对象    UIImage *image = self.images[app.icon];    if (image) {        // 若缓存中存在图片        cell.imageView.image = image;    }else    {        // 若缓存中不存在图片，则图片要从网上下载        // 设置下载前系统刷出的图片        cell.imageView.image = [UIImage imageNamed:@"身份证小"];                // 基础差，下面这行不太理解        DYFDownloadOperation *operation = self.oprations[app.icon];        if (operation) {            // 若正在下载，则不执行其它操作        }else        {            // 若没在下载，则创建开始下载的子线程            DYFDownloadOperation *operation = [[DYFDownloadOperation alloc] init];            operation.url = app.icon;            operation.indexPath = indexPath;            operation.delegate = self;            // 添加任务进队列，异步下载            [self.queue addOperation:operation];            // 基础差，下面这行不太理解            self.oprations[app.icon] = operation;        }    }        // 3.返回cell    return cell;}#pragma mark - DYFDownloadOperationDelegate- (void)downloadOperation:(DYFDownloadOperation *)operation didFinishedDownload:(UIImage *)image{    // 1.删除执行完毕的下载操作    [self.oprations removeObjectForKey:operation.url];    // 若图片下载好    if (image) {        // 2.将下载好的图片存入缓存        self.images[operation.url] = image;        // 3.刷新这一行cell的数据        [self.tableView reloadRowsAtIndexPaths:@[operation.indexPath] withRowAnimation:UITableViewRowAnimationNone];        // 4.将图片存入沙盒                // 4.1图片先转换为2进制数据        NSData *data = http://www.mamicode.com/UIImagePNGRepresentation(image);"%@", path);        // 4.3保存data到path中        [data writeToFile:path atomically:YES];    }}// 开始拖拽时候暂停队列- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView{    [self.queue setSuspended:YES];}// 停止拖拽的时候重启队列- (void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset{    [self.queue setSuspended:NO];}@end