虽然TableView的重用机制很好用,但是....总有一些很尴尬的业务场景…比如定时器的复用…假如在Cell中定义一个定时器简直重用起来就是爆炸...写之前我也翻阅了一些简书相关的文章,但是...实现起来都太过繁琐和复杂了,有使用通知的(这黑科技)还有用数组把秒数装起来的(坑爹???)….简直不堪入目...所以我决定自己动手丰衣足食,下面开搞吧
思路现实##
_面向对象开发,既然每一个秒杀的数据都是一个对象,只要我让每一个对象都管理自己的定时器不就行了?何必又通知又数组的....同时重用机制每次都是按照indexPath来取自身的Model更加不用纠结定时器重用的问题..好吧,应该这样写,问题都能迎刃而解吧??....先试试再说.. _
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首先是通过网络数据转化为Model...
'' // SeckillListModel.h
'' //
'' // Created by HuaZao on 16/9/13.
'' // Copyright © 2016年 HuaZaoGYJ. All rights reserved.
'' //
''
'' #import <Foundation/Foundation.h>
''
'' typedef NS_OPTIONS(NSUInteger,SeckillState) {
'' //未开始
'' SeckillUnStart = 0,
'' //进行中
'' SeckillStarting,
'' //已经结束
'' SeckillOver,
'' };
''
'' @interface SeckillListModel : NSObject
''
'' @property (strong,nonatomic) dispatch_source_t timer;
''
'' /** 图片 */
'' @property (nonatomic, copy) NSString* logoImageList;
''
'' /** 产品唯一ID */
'' @property (nonatomic, copy) NSString* product_mark_id;
''
'' /** 商品ID */
'' @property (nonatomic, assign) NSInteger Id;
''
'' /** 秒杀时间 */
'' @property (nonatomic, copy) NSString* seckill_time;
''
'' /** 秒杀保持时间 */
'' @property (nonatomic, assign) NSInteger keep_time;
''
'' /** 已经等待了多长时间 */
'' @property (nonatomic, assign) NSInteger waitTime;
''
'' /** 秒杀已经过去的时间 */
'' @property (nonatomic, assign) NSInteger pass_time;
''
'' /** 服务器离开始秒杀或者结束秒杀的时间差 */
'' @property (nonatomic, assign) NSInteger diffTime;
''
'' /** 名字 */
'' @property (nonatomic, copy) NSString* name;
''
'' /** 状态 */
'' @property (nonatomic, assign) SeckillState state;
''
'' /** 价钱 */
'' @property (nonatomic, assign) CGFloat price;
''
'' @end
''
Model中的** timer**字段就是负责这个秒杀产品的定时器,这个很重要整个实现的核心!
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接下来就是我们撸一个Cell出来
''//
'' // seckillingCollectionViewCell.m
'' //
'' // Created by HuaZao on 16/9/12.
'' // Copyright © 2016年 HuaZaoGYJ. All rights reserved.
'' //
''
'' #import "seckillingCollectionViewCell.h"
''
'' @interface seckillingCollectionViewCell()
''
''
'' @end
''
'' @implementation seckillingCollectionViewCell
''
''
'' -(void)loadCellDataWithProductInfoModel:(SeckillListModel *)model{
'' self.goodStr.text = model.name;
'' [self.goodImageView sd_setImageWithURL:[NSURL URLWithString:model.logoImageList] placeholderImage:[UIImage imageNamed:@"ty_tpjzsb_img_nor"]];
'' switch (model.state) {
'' case SeckillUnStart:
'' self.seckillWaitView.hidden = NO;
'' self.seckillOverView.hidden = YES;
'' self.seckillStartView.hidden = YES;
'' self.seckillWaitTime.text = model.seckill_time;
'' [self startSeckillWithModel:model];
'' break;
'' case SeckillStarting:
'' self.seckillWaitView.hidden = YES;
'' self.seckillOverView.hidden = YES;
'' self.seckillStartView.hidden = NO;
'' //开始倒计时
'' [self starTimeCountWithModel:model];
'' break;
'' case SeckillOver:
'' self.seckillWaitView.hidden = YES;
'' self.seckillOverView.hidden = NO;
'' self.seckillStartView.hidden = YES;
'' break;
'' default:
'' break;
'' }
'' }
''
''
'' /*开始秒杀*/
'' -(void)startSeckillWithModel:(SeckillListModel *)model{
'' //应该去秒杀了
'' if (model.diffTime == 0) {
'' [self starTimeCountWithModel:model];
'' return;
'' }
''
'' //取真正的时间差
'' __block NSInteger countDiffTime = model.diffTime - model.pass_time;
''
''
'' if (model.timer == nil){
'' dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
'' model.timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0,queue);
'' dispatch_source_set_timer(model.timer,dispatch_walltime(NULL, 0),1.0*NSEC_PER_SEC, 0); //每秒执行
'' //启动定时器
'' dispatch_resume(model.timer);
'' }
''
'' dispatch_source_set_event_handler(model.timer, ^{
'' countDiffTime --;
'' NSLog(@"商品秒杀倒计时-----%d---%@--",countDiffTime,model.timer);
'' if (countDiffTime == 0) {
'' //关闭这个定时器
'' dispatch_source_cancel(model.timer);
'' model.timer = nil;
'' model.pass_time = 0;
'' model.diffTime = 0;
'' model.state = SeckillStarting;
'' [self starTimeCountWithModel:model];
'' dispatch_async(dispatch_get_main_queue(), ^{
'' self.seckillWaitView.hidden = YES;
'' self.seckillOverView.hidden = YES;
'' self.seckillStartView.hidden = NO;
'' });
'' }
'' });
''
'' }
''
''
'' /*已经在秒杀了*/
'' -(void)starTimeCountWithModel:(SeckillListModel *)model{
''
'' //已经秒完了
'' if (model.pass_time >= model.keep_time || model.diffTime == model.keep_time){
'' self.seckillWaitView.hidden = YES;
'' self.seckillOverView.hidden = NO;
'' self.seckillStartView.hidden = YES;
'' return;
'' }
''
'' //取真正的时间差
'' NSInteger deffTime = model.keep_time - model.diffTime - model.pass_time;
''
'' //转分钟
'' __block NSInteger seckillHour = (deffTime/3600);
'' __block NSInteger seckillMinute = (deffTime/60) % 60;
'' __block NSInteger seckillSecond = deffTime % 60;
''
'' if (model.timer == nil) {
'' dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
'' model.timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0,queue);
'' dispatch_source_set_timer(model.timer,dispatch_walltime(NULL, 0),1.0*NSEC_PER_SEC, 0); //每秒执行
'' //启动定时器
'' dispatch_resume(model.timer);
'' }
''
'' dispatch_source_set_event_handler(model.timer, ^{
'' seckillSecond --;
'' if (seckillSecond == 0) {
'' if (seckillMinute == 0) {
'' seckillMinute = 0;
''
'' }else{
'' seckillMinute --;
'' seckillSecond = 60;
'' }
'' }
''
'' if (seckillMinute == 0) {
'' if (seckillHour == 0) {
'' seckillHour = 0;
'' }else{
'' seckillHour --;
'' seckillMinute = 60;
'' }
'' }
''
'' NSLog(@"-----%d---%@--",model.pass_time,model.timer);
'' if (seckillHour == 0 && seckillMinute ==0 && seckillSecond == 0) {
'' //关闭这个定时器
'' dispatch_source_cancel(model.timer);
'' model.timer = nil;
'' model.pass_time = 0;
'' dispatch_async(dispatch_get_main_queue(), ^{
'' self.seckillWaitView.hidden = YES;
'' self.seckillOverView.hidden = NO;
'' self.seckillStartView.hidden = YES;
'' });
'' }
'' dispatch_async(dispatch_get_main_queue(), ^{
'' self.seckillTime.text = [NSString stringWithFormat:@"%02d:%02d:%02d",(int)seckillHour,(int)seckillMinute,(int)seckillSecond];
'' });
'' });
''
'' }
'' '' @end
''
''
**上面的代码比较多,其实核心代码就几句**
'' if (model.timer == nil){
'' '' dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
'' '' model.timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0,queue);
'' '' dispatch_source_set_timer(model.timer,dispatch_walltime(NULL, 0),1.0*NSEC_PER_SEC, 0);
'' '' dispatch_resume(model.timer);
'' '' }
'' '' dispatch_source_set_event_handler(model.timer, ^{
'' //做你要处理的事情
'' });
我们只保证每一个Model的定时器只存在一个Cell重用的时候我们就照样拿出来执行dispatch_source_set_event_handler这个函数就没问题了..这样我们上面的需求已经差不多实现了..不过总觉得差了一点什么.....总有点不对劲....如果这个Model定时器没初始化到岂不是坑爹????这样会造成巨大误差....下面把这个问题解决了吧...那我只需要…在拿到数据的时候计时已经过去的时间不就可以了吗???
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解决Cell没有初始化定时器造成的问题
在控制器或者View中定义一个定时器,用来计时已经过去了多少时间
''@implementation seckillingView
''
'' /*开始倒计时多余的时间*/
'' -(void)countPassTime{
'' dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
'' _passTime = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0,queue);
'' dispatch_source_set_timer(_passTime,dispatch_walltime(NULL, 0),1.0*NSEC_PER_SEC, 0); //每秒执行
'' dispatch_source_set_event_handler(_passTime, ^{
'' for (SeckillListModel *model in self.viewModel.seckillDataSource) {
'' model.pass_time ++;
'' }
'' });
'' //启动定时器
'' dispatch_resume(_passTime);
'' }
'' @end
在Model中定义一个PassTime用来计算过去的多少时间,具体逻辑可以看前面Cell的实现,我们只需要把服务器时间减去passtime这样就可以解决刚刚的问题了,运行了一下基本实现需求了....收工0.0
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View源码
''//
'' // seckillingView.m
'' //
'' // Created by HuaZao on 16/9/12.
'' // Copyright © 2016年 HuaZaoGYJ. All rights reserved.
'' //
'' #import "seckillingCollectionViewCell.h"
'' #import "seckillingView.h"
'' #import "TTDKillGoodInfoViewController.h"
'' #import "indexViewController.h"
'' @interface seckillingView()<UICollectionViewDelegate,UICollectionViewDataSource,UICollectionViewDelegateFlowLayout>
''
'' @property (strong,nonatomic) dispatch_source_t passTime;
''
'' @end
''
'' @implementation seckillingView
''
'' /*开始倒计时多余的时间*/
'' -(void)countPassTime{
'' dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
'' _passTime = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0,queue);
'' dispatch_source_set_timer(_passTime,dispatch_walltime(NULL, 0),1.0*NSEC_PER_SEC, 0); //每秒执行
'' dispatch_source_set_event_handler(_passTime, ^{
'' for (SeckillListModel *model in self.viewModel.seckillDataSource) {
'' model.pass_time ++;
'' }
'' });
'' //启动定时器
'' dispatch_resume(_passTime);
'' }
''
'' -(NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section{
'' return self.viewModel.seckillDataSource.count;
'' }
''
'' -(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
'' seckillingCollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"seckillCell" forIndexPath:indexPath];
'' [cell loadCellDataWithProductInfoModel:self.viewModel.seckillDataSource[indexPath.row]];
'' return cell;
'' }
''
''
'' -(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath{
'' TTDKillGoodInfoViewController *killVc = [[TTDKillGoodInfoViewController alloc] init];
'' killVc.seckModel = self.viewModel.seckillDataSource[indexPath.row];
'' killVc.goodId = self.viewModel.seckillDataSource[indexPath.row].product_mark_id;
'' [self.viewModel.indexVc.navigationController pushViewController:killVc animated:YES];
'' }
''
''
'' @end
