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最新推荐文章于 2022-09-12 13:54:09 发布

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最新推荐文章于 2022-09-12 13:54:09 发布

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原文链接：http://www.cnblogs.com/pengsi/p/5355744.html

本文探讨了iOS应用中网络请求、引导页显示、内存警告处理、子类化单元格复用、UIMenuController使用及界面复用控制器简化代码的实践。重点介绍了如何在应用中优化内存管理，避免崩溃并提升用户体验。

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1.网络请求显示,请求成功显示,请求失败隐藏:

//显示状态栏的网络指示器

[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;

2.是否显示引导页:

 1 //是否显示引导页
 2 -(void)showGuiView {
 3     
 4     //获得当前版本号
 5     NSString *currentVersion = [NSBundle mainBundle].infoDictionary[@"CFBundleShortVersionString"];
 6     //沙盒版本号
 7     NSString *lastVersion = [[NSUserDefaults standardUserDefaults] stringForKey:@"CFBundleShortVersionString"];
 8     
 9     if (![currentVersion isEqualToString:lastVersion]) {
10         XFGuideView *guideView = [XFGuideView guideView];
11         guideView.frame = self.window.bounds;
12         [self.window addSubview:guideView];
13         
14         [[NSUserDefaults standardUserDefaults] setObject:currentVersion forKey:@"CFBundleShortVersionString"];
15         //马上写入沙盒
16         [[NSUserDefaults standardUserDefaults] synchronize];
17         
18     }
19 }

3.内存警告停止下载图片:

1 //当收到Received memory warning.会调用次方法
2 -(void)applicationDidReceiveMemoryWarning:(UIApplication *)application {
3     SDWebImageManager *mgr = [SDWebImageManager sharedManager];
4     //取消下载
5     [mgr cancelAll];
6     //清空缓存
7     [mgr.imageCache clearMemory];
8 
9 }

4.在子类化单元格类中:

// 从队列里面复用时调用

- (void)prepareForReuse {

[super prepareForReuse];

[_videoView reset];

[_voiceView reset];

}

5.UIMenuController的使用:

-(IBAction)panGestureTop:(UILongPressGestureRecognizer *)longPress

02.{
03. 
04.UIMenuItem * itemPase = [[UIMenuItem alloc] initWithTitle:@"复制" action:@selector(copyimage)];
05.UIMenuItem * itemTrans = [[UIMenuItem alloc] initWithTitle:@"转发" action:@selector(trans)];
06.UIMenuItem * itemCollect = [[UIMenuItem alloc] initWithTitle:@"收藏" action:@selector(collect)];
07.UIMenuItem * itemJoin = [[UIMenuItem alloc] initWithTitle:@"加入" action:@selector(join)];
08. 
09.UIMenuController * menuController = [UIMenuController sharedMenuController];
10.[menuController setMenuItems: @[itemPase,itemCollect,itemTrans,itemJoin]];
11. 
12.CGPoint location = [longPress locationInView:[longPress view]];
13.CGRect menuLocation = CGRectMake(location.x, location.y, 0, 0);
14.[menuController setTargetRect:menuLocation inView:[longPress view]];
15.menuController.arrowDirection = UIMenuControllerArrowDown;
16. 
17.[menuController setMenuVisible:YES animated:YES];
18. 
19.}