1、禁止手机睡眠

[UIApplication sharedApplication].idleTimerDisabled = YES;

2、隐藏表格某行cell

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    // 如果是你需要隐藏的那一行，返回高度为0
    return (indexPath.row == YouWantToHideRow) ? 0 : 44;
}

// 然后再你需要隐藏cell的时候调用
[self.tableView beginUpdates];
[self.tableView endUpdates];

3、禁用Button亮

button.adjustsImageWhenHighlighted = NO;
或者在创建的时候
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];

4、动画切换window的根控制器

// options是动画选项
[UIView transitionWithView:[UIApplication sharedApplication].keyWindow duration:0.5f options:UIViewAnimationOptionTransitionCrossDissolve animations:^{
        BOOL oldState = [UIView areAnimationsEnabled];
        [UIView setAnimationsEnabled:NO];
        [UIApplication sharedApplication].keyWindow.rootViewController = [RootViewController new];
        [UIView setAnimationsEnabled:oldState];
    } completion:^(BOOL finished) {

    }];

5、去除数组中重复的元素

NSArray *newArr = [oldArr valueForKeyPath:@“@distinctUnionOfObjects.self"];

6、在iOS8.0系统中，表格的内容显示不全，且事件无法响应问题

去实现tableView的heightForRowAtIndexPath这个方法试一试

7、iOS8.0中实现表格的侧滑功能必须实现下面这个方法，否则无法侧滑

// 必须写的方法，和editActionsForRowAtIndexPath配对使用，里面什么不写也行
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {

}

8、进入app权限设置

// 跳进app设置
if (UIApplicationOpenSettingsURLString != NULL) {
    UIApplication *application = [UIApplication sharedApplication];
    NSURL *URL = [NSURL URLWithString:UIApplicationOpenSettingsURLString];
    if ([application respondsToSelector:@selector(openURL:options:completionHandler:)]) {
        [application openURL:URL options:@{} completionHandler:nil];
    } else {
        [application openURL:URL];
    }
}

9、collectionView的内容小于其宽高的时候是不能滚动的，设置可以滚动：

collectionView.alwaysBounceHorizontal = YES;
collectionView.alwaysBounceVertical = YES;

10、设置navigationBar上的title颜色和大小

[self.navigationController.navigationBar setTitleTextAttributes:@{NSForegroundColorAttributeName : [UIColor youColor], NSFontAttributeName : [UIFont systemFontOfSize:15]}]

11、常用的宏定义

• 强／弱引用

#define WEAK_SELF typeof(self) __weak weakSelf = self;
#define STRONG_SELF typeof(weakSelf) __strong strongSelf = weakSelf;

• 由角度转换弧度

#define DegreesToRadian(x) (M_PI * (x) / 180.0)

• 由弧度转换角度

#define RadianToDegrees(radian) (radian*180.0)/(M_PI)

• 获取图片资源

#define GetImage(imageName) [UIImage imageNamed:[NSString stringWithFormat:@"%@",imageName]]

• 获取temp

#define PathTemp NSTemporaryDirectory()

• 获取沙盒Document

#define PathDocument [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject]

• 获取沙盒Cache

#define PathCache [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) firstObject]

• 自定义Debug日志

#pragma mark - Debug日志
#ifdef DEBUG
#    define DLog(...) NSLog(__VA_ARGS__)
#    define FLog(s) NSLog(@"[%@-%@]:\n%@",NSStringFromClass([self class]),NSStringFromSelector(_cmd),s)
#    define TLog(...) NSLog(@"[%@-%@]:\n%@",NSStringFromClass([self class]),NSStringFromSelector(_cmd),[NSString stringWithFormat:__VA_ARGS__])
#else
#    define DLog(...)
#    define FLog(...)
#    define TLog(...)
#endif

• GCD延迟执行

//延迟执行
#define DISPATCH_AFTER(delayInSeconds,block) dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC)), dispatch_get_main_queue(), block)
#define DISPATCH_ASYNC_GET_MAIN(block) dispatch_async(dispatch_get_main_queue(), block)
#define DISPATCH_ASYNC_GET_GLOBAL(block) dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), block)

12、随机颜色

+ (UIColor *)RandomColor {
    NSInteger aRedValue = arc4random() % 255;
    NSInteger aGreenValue = arc4random() % 255;
    NSInteger aBlueValue = arc4random() % 255;
    UIColor *randColor = [UIColor colorWithRed:aRedValue / 255.0f green:aGreenValue / 255.0f blue:aBlueValue / 255.0f alpha:1.0f];
    return randColor;
}

13、获取window

+(UIWindow*)getWindow {
    UIWindow* win = nil; //[UIApplication sharedApplication].keyWindow;
    for (id item in [UIApplication sharedApplication].windows) {
        if ([item class] == [UIWindow class]) {
            if (!((UIWindow*)item).hidden) {
                win = item;
                break;
            }
        }
    }
    return win;
}

14、修改textField的placeholder的字体颜色、大小

[textField setValue:[UIColor redColor] forKeyPath:@"_placeholderLabel.textColor"];
[textField setValue:[UIFont boldSystemFontOfSize:16] forKeyPath:@"_placeholderLabel.font"];

15、统一收起键盘

[[[UIApplication sharedApplication] keyWindow] endEditing:YES];

16、控制屏幕旋转，在控制器中写

// 是否支持自动转屏
- (BOOL)shouldAutorotate {
    return YES;
}

// 支持哪些屏幕方向
- (UIInterfaceOrientationMask)supportedInterfaceOrientations {
    return UIInterfaceOrientationMaskLandscapeLeft | UIInterfaceOrientationMaskLandscapeRight;
}

// 默认的屏幕方向（当前ViewController必须是通过模态出来的UIViewController（模态带导航的无效）方式展现出来的，才会调用这个方法
- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation {
    return UIInterfaceOrientationLandscapeLeft | UIInterfaceOrientationLandscapeRight;
}

17、获取app缓存大小

- (CGFloat)getCachSize {

    NSUInteger imageCacheSize = [[SDImageCache sharedImageCache] getSize];
    //获取自定义缓存大小
    //用枚举器遍历 一个文件夹的内容
    //1.获取 文件夹枚举器
    NSString *myCachePath = [NSHomeDirectory() stringByAppendingPathComponent:@"Library/Caches"];
    NSDirectoryEnumerator *enumerator = [[NSFileManager defaultManager] enumeratorAtPath:myCachePath];
    __block NSUInteger count = 0;
    //2.遍历
    for (NSString *fileName in enumerator) {
        NSString *path = [myCachePath stringByAppendingPathComponent:fileName];
        NSDictionary *fileDict = [[NSFileManager defaultManager] attributesOfItemAtPath:path error:nil];
        count += fileDict.fileSize;//自定义所有缓存大小
    }
    // 得到是字节  转化为M
    CGFloat totalSize = ((CGFloat)imageCacheSize+count)/1024/1024;
    return totalSize;
}

18、清理app缓存

- (void)handleClearView {
    //删除两部分
    //1.删除 sd 图片缓存
    //先清除内存中的图片缓存
    [[SDImageCache sharedImageCache] clearMemory];
    //清除磁盘的缓存
    [[SDImageCache sharedImageCache] clearDisk];
    //2.删除自己缓存
    NSString *myCachePath = [NSHomeDirectory() stringByAppendingPathComponent:@"Library/Caches"];
    [[NSFileManager defaultManager] removeItemAtPath:myCachePath error:nil];
}

19、长按复制功能

- (void)viewDidLoad
{
    [self.view addGestureRecognizer:[[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(pasteBoard:)]];
}
- (void)pasteBoard:(UILongPressGestureRecognizer *)longPress {
    if (longPress.state == UIGestureRecognizerStateBegan) {
        UIPasteboard *pasteboard = [UIPasteboard generalPasteboard];
        pasteboard.string = @"需要复制的文本";
    }
}

20、获取手机和app信息

NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
CFShow(infoDictionary);
// app名称
NSString *app_Name = [infoDictionary objectForKey:@"CFBundleDisplayName"];
// app版本
NSString *app_Version = [infoDictionary objectForKey:@"CFBundleShortVersionString"];
// app build版本
NSString *app_build = [infoDictionary objectForKey:@"CFBundleVersion"];

    //手机序列号
    NSString* identifierNumber = [[UIDevice currentDevice] uniqueIdentifier];
    NSLog(@"手机序列号: %@",identifierNumber);
    //手机别名： 用户定义的名称
    NSString* userPhoneName = [[UIDevice currentDevice] name];
    NSLog(@"手机别名: %@", userPhoneName);
    //设备名称
    NSString* deviceName = [[UIDevice currentDevice] systemName];
    NSLog(@"设备名称: %@",deviceName );
    //手机系统版本
    NSString* phoneVersion = [[UIDevice currentDevice] systemVersion];
    NSLog(@"手机系统版本: %@", phoneVersion);
    //手机型号
    NSString* phoneModel = [[UIDevice currentDevice] model];
    NSLog(@"手机型号: %@",phoneModel );
    //地方型号  （国际化区域名称）
    NSString* localPhoneModel = [[UIDevice currentDevice] localizedModel];
    NSLog(@"国际化区域名称: %@",localPhoneModel );

    NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
    // 当前应用名称
    NSString *appCurName = [infoDictionary objectForKey:@"CFBundleDisplayName"];
    NSLog(@"当前应用名称：%@",appCurName);
    // 当前应用软件版本  比如：1.0.1
    NSString *appCurVersion = [infoDictionary objectForKey:@"CFBundleShortVersionString"];
    NSLog(@"当前应用软件版本:%@",appCurVersion);
    // 当前应用版本号码  int类型
    NSString *appCurVersionNum = [infoDictionary objectForKey:@"CFBundleVersion"];
    NSLog(@"当前应用版本号码：%@",appCurVersionNum);