记录几个可能用到的iOS方法

方法来自：http://www.cocoachina.com/ios/20170626/19616.html

看到大神总结的一些东西，记录几个自己觉得会用的到的。

1、禁止手机睡眠

[UIApplication sharedApplication].idleTimerDisabled = YES;

2、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) {
    }];

3、去除数组中重复的对象

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

4、跳进app权限设置

// 跳进app设置
            if (UIApplicationOpenSettingsURLString != NULL) {
                NSURL *url = [NSURL URLWithString:UIApplicationOpenSettingsURLString];
                [[UIApplication sharedApplication] openURL:url];
            }

5、给一个view截图

   UIGraphicsBeginImageContextWithOptions(view.bounds.size, YES, 0.0);
    [view.layer renderInContext:UIGraphicsGetCurrentContext()];
    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

6、强／弱引用

#define WeakSelf(type)  __weak typeof(type) weak##type = type; // weak
#define StrongSelf(type)  __strong typeof(type) type = weak##type; // strong

7、自定义NSLog

#ifdef DEBUG
#define DLog(fmt, ...) NSLog((@"%s [Line %d] " fmt), __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__)
#else
#define DLog(...)
#endif

8、FORMAT

#define FORMAT(f, ...)      [NSString stringWithFormat:f, ## __VA_ARGS__]

9、通知

#define NOTIF_ADD(n, f)     [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(f) name:n object:nil]
#define NOTIF_POST(n, o)    [[NSNotificationCenter defaultCenter] postNotificationName:n object:o]
#define NOTIF_REMV()        [[NSNotificationCenter defaultCenter] removeObserver:self]

10、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"];

11、统一收起键盘

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

12、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;
}

13、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;
}

14、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];
}

15、几个常用权限判断

if ([CLLocationManager authorizationStatus] ==kCLAuthorizationStatusDenied) {
        NSLog(@"没有定位权限");
}
AVAuthorizationStatus statusVideo = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo];
if (statusVideo == AVAuthorizationStatusDenied) {
    NSLog(@"没有摄像头权限");
}
//是否有麦克风权限
AVAuthorizationStatus statusAudio = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeAudio];
if (statusAudio == AVAuthorizationStatusDenied) {
    NSLog(@"没有录音权限");
}
[PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {
   if (status == PHAuthorizationStatusDenied) {
        NSLog(@"没有相册权限");
   }
}];

16、获取手机型号

 + (NSString *)getDeviceInfo {
    struct utsname systemInfo;
    uname(&systemInfo);
    NSString *platform = [NSString stringWithCString:systemInfo.machine encoding:NSASCIIStringEncoding];
    if ([platform isEqualToString:@"iPhone1,1"]) return @"iPhone 2G";
    if ([platform isEqualToString:@"iPhone1,2"]) return @"iPhone 3G";
    if ([platform isEqualToString:@"iPhone2,1"]) return @"iPhone 3GS";
    if ([platform isEqualToString:@"iPhone3,1"]) return @"iPhone 4";
    if ([platform isEqualToString:@"iPhone3,2"]) return @"iPhone 4";
    if ([platform isEqualToString:@"iPhone3,3"]) return @"iPhone 4";
    if ([platform isEqualToString:@"iPhone4,1"]) return @"iPhone 4S";
    if ([platform isEqualToString:@"iPhone5,1"]) return @"iPhone 5";
    if ([platform isEqualToString:@"iPhone5,2"]) return @"iPhone 5";
    if ([platform isEqualToString:@"iPhone5,3"]) return @"iPhone 5c";
    if ([platform isEqualToString:@"iPhone5,4"]) return @"iPhone 5c";
    if ([platform isEqualToString:@"iPhone6,1"]) return @"iPhone 5s";
    if ([platform isEqualToString:@"iPhone6,2"]) return @"iPhone 5s";
    if ([platform isEqualToString:@"iPhone7,1"]) return @"iPhone 6 Plus";
    if ([platform isEqualToString:@"iPhone7,2"]) return @"iPhone 6";
    if ([platform isEqualToString:@"iPhone8,1"]) return @"iPhone 6s";
    if ([platform isEqualToString:@"iPhone8,2"]) return @"iPhone 6s Plus";
    // 日行两款手机型号均为日本独占，可能使用索尼FeliCa支付方案而不是苹果支付
    if ([platform isEqualToString:@"iPhone9,1"])    return @"国行、日版、港行iPhone 7";
    if ([platform isEqualToString:@"iPhone9,2"])    return @"港行、国行iPhone 7 Plus";
    if ([platform isEqualToString:@"iPhone9,3"])    return @"美版、台版iPhone 7";
    if ([platform isEqualToString:@"iPhone9,4"])    return @"美版、台版iPhone 7 Plus";
    if ([platform isEqualToString:@"iPhone8,4"]) return @"iPhone SE";
    if ([platform isEqualToString:@"iPod1,1"]) return @"iPod Touch 1G";
    if ([platform isEqualToString:@"iPod2,1"]) return @"iPod Touch 2G";
    if ([platform isEqualToString:@"iPod3,1"]) return @"iPod Touch 3G";
    if ([platform isEqualToString:@"iPod4,1"]) return @"iPod Touch 4G";
    if ([platform isEqualToString:@"iPod5,1"]) return @"iPod Touch 5G";
    if ([platform isEqualToString:@"iPad1,1"]) return @"iPad 1G";
    if ([platform isEqualToString:@"iPad2,1"]) return @"iPad 2";
    if ([platform isEqualToString:@"iPad2,2"]) return @"iPad 2";
    if ([platform isEqualToString:@"iPad2,3"]) return @"iPad 2";
    if ([platform isEqualToString:@"iPad2,4"]) return @"iPad 2";
    if ([platform isEqualToString:@"iPad2,5"]) return @"iPad Mini 1G";
    if ([platform isEqualToString:@"iPad2,6"]) return @"iPad Mini 1G";
    if ([platform isEqualToString:@"iPad2,7"]) return @"iPad Mini 1G";
    if ([platform isEqualToString:@"iPad3,1"]) return @"iPad 3";
    if ([platform isEqualToString:@"iPad3,2"]) return @"iPad 3";
    if ([platform isEqualToString:@"iPad3,3"]) return @"iPad 3";
    if ([platform isEqualToString:@"iPad3,4"]) return @"iPad 4";
    if ([platform isEqualToString:@"iPad3,5"]) return @"iPad 4";
    if ([platform isEqualToString:@"iPad3,6"]) return @"iPad 4";
    if ([platform isEqualToString:@"iPad4,1"]) return @"iPad Air";
    if ([platform isEqualToString:@"iPad4,2"]) return @"iPad Air";
    if ([platform isEqualToString:@"iPad4,3"]) return @"iPad Air";
    if ([platform isEqualToString:@"iPad4,4"]) return @"iPad Mini 2G";
    if ([platform isEqualToString:@"iPad4,5"]) return @"iPad Mini 2G";
    if ([platform isEqualToString:@"iPad4,6"]) return @"iPad Mini 2G";
    if ([platform isEqualToString:@"i386"]) return @"iPhone Simulator";
    if ([platform isEqualToString:@"x86_64"]) return @"iPhone Simulator";
    return platform;
}

17、判断图片类型

//通过图片Data数据第一个字节 来获取图片扩展名
- (NSString *)contentTypeForImageData:(NSData *)data
{
    uint8_t c;
    [data getBytes:&c length:1];
    switch (c)
    {
        case 0xFF:
            return @"jpeg";
 
        case 0x89:
            return @"png";
 
        case 0x47:
            return @"gif";
 
        case 0x49:
        case 0x4D:
            return @"tiff";
 
        case 0x52:
        if ([data length] < 12) {
            return nil;
        }
 
        NSString *testString = [[NSString alloc] initWithData:[data subdataWithRange:NSMakeRange(0, 12)] encoding:NSASCIIStringEncoding];
        if ([testString hasPrefix:@"RIFF"]
            && [testString hasSuffix:@"WEBP"])
        {
            return @"webp";
        }
 
        return nil;
    }
 
    return nil;
}

18、强制使用系统键盘

//强制使用系统键盘
- (BOOL)[application](http://www.knowsky.com/tag-9.html):(UIApplication *)application
shouldAllowExtensionPointIdentifier:(NSString *)extensionPointIdentifier
{
    if ([extensionPointIdentifier isEqualToString:@"com.apple.keyboard-service"]) {
        return NO;
    }
    return YES;
}

19、拿到当前正在显示的控制器，不管是push进去的，还是present进去的都能拿到

- (UIViewController *)getVisibleViewControllerFrom:(UIViewController*)vc {
    if ([vc isKindOfClass:[UINavigationController class]]) {
        return [self getVisibleViewControllerFrom:[((UINavigationController*) vc) visibleViewController]];
    }else if ([vc isKindOfClass:[UITabBarController class]]){
        return [self getVisibleViewControllerFrom:[((UITabBarController*) vc) selectedViewController]];
    } else {
        if (vc.presentedViewController) {
            return [self getVisibleViewControllerFrom:vc.presentedViewController];
        } else {
            return vc;
        }
    }
}

20、网络状态监听

NetworkStatus status = [[Reachability reachabilityForInternetConnection] currentReachabilityStatus];
if (status == NotReachable) {
    NSLog(@"当前设备无网络");
}
if (status == ReachableViaWiFi) {
    NSLog(@"当前wifi网络");
}
if (status == NotReachable) {
    NSLog(@"当前蜂窝移动网络");
}

// 监听网络状况
    AFNetworkReachabilityManager *mgr = [AFNetworkReachabilityManager sharedManager];
    [mgr setReachabilityStatusChangeBlock:^(AFNetworkReachabilityStatus status) {
        switch (status) {
            case AFNetworkReachabilityStatusUnknown:
                break;
            case AFNetworkReachabilityStatusNotReachable: {
                [SVProgressHUD showInfoWithStatus:@"当前设备无网络"];
            }
                break;
            case AFNetworkReachabilityStatusReachableViaWiFi:
                [SVProgressHUD showInfoWithStatus:@"当前Wi-Fi网络"];
                break;
            case AFNetworkReachabilityStatusReachableViaWWAN:
                [SVProgressHUD showInfoWithStatus:@"当前蜂窝移动网络"];
                break;
            default:
                break;
        }
    }];
    [mgr startMonitoring];

21、透明颜色不影响子视图透明度

    [UIColor colorWithRed: green: blue: alpha:];

22、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";
    }
}

23、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);

24、导入自定义字体库

1、找到你想用的字体的 ttf 格式，拖入工程
2、在工程的plist中增加一行数组，“Fonts provided by application”
3、为这个key添加一个item，value为你刚才导入的ttf文件名
4、直接使用即可：label.font = [UIFont fontWithName:@"你刚才导入的ttf文件名" size:20.0]；

25、让label的文字内容显示在左上／右上／左下／右下／中心顶／中心底部

自定义UILabel
// 重写label的textRectForBounds方法
- (CGRect)textRectForBounds:(CGRect)bounds limitedToNumberOfLines:(NSInteger)numberOfLines {
    CGRect rect = [super textRectForBounds:bounds limitedToNumberOfLines:numberOfLines];
    switch (self.textAlignmentType) {
        case WZBTextAlignmentTypeLeftTop: {
            rect.origin = bounds.origin;
        }
            break;
        case WZBTextAlignmentTypeRightTop: {
            rect.origin = CGPointMake(CGRectGetMaxX(bounds) - rect.size.width, bounds.origin.y);
        }
            break;
        case WZBTextAlignmentTypeLeftBottom: {
            rect.origin = CGPointMake(bounds.origin.x, CGRectGetMaxY(bounds) - rect.size.height);
        }
            break;
        case WZBTextAlignmentTypeRightBottom: {
            rect.origin = CGPointMake(CGRectGetMaxX(bounds) - rect.size.width, CGRectGetMaxY(bounds) - rect.size.height);
        }
            break;
        case WZBTextAlignmentTypeTopCenter: {
            rect.origin = CGPointMake((CGRectGetWidth(bounds) - CGRectGetWidth(rect)) / 2, CGRectGetMaxY(bounds) - rect.origin.y);
        }
            break;
        case WZBTextAlignmentTypeBottomCenter: {
            rect.origin = CGPointMake((CGRectGetWidth(bounds) - CGRectGetWidth(rect)) / 2, CGRectGetMaxY(bounds) - CGRectGetMaxY(bounds) - rect.size.height);
        }
            break;
        case WZBTextAlignmentTypeLeft: {
            rect.origin = CGPointMake(0, rect.origin.y);
        }
            break;
        case WZBTextAlignmentTypeRight: {
            rect.origin = CGPointMake(rect.origin.x, 0);
        }
            break;
        case WZBTextAlignmentTypeCenter: {
            rect.origin = CGPointMake((CGRectGetWidth(bounds) - CGRectGetWidth(rect)) / 2, (CGRectGetHeight(bounds) - CGRectGetHeight(rect)) / 2);
        }
            break;
        default:
            break;
    }
    return rect;
}
- (void)drawTextInRect:(CGRect)rect {
    CGRect textRect = [self textRectForBounds:rect limitedToNumberOfLines:self.numberOfLines];
    [super drawTextInRect:textRect];
}

26、UILabel设置内边距

子类化UILabel，重写drawTextInRect方法
- (void)drawTextInRect:(CGRect)rect {
    // 边距，上左下右
    UIEdgeInsets insets = {0, 5, 0, 5};
    [super drawTextInRect:UIEdgeInsetsInsetRect(rect, insets)];
}

27、UILabel设置文字描边

子类化UILabel，重写drawTextInRect方法
- (void)drawTextInRect:(CGRect)rect
{
    CGContextRef c = UIGraphicsGetCurrentContext();
    // 设置描边宽度
    CGContextSetLineWidth(c, 1);
    CGContextSetLineJoin(c, kCGLineJoinRound);
    CGContextSetTextDrawingMode(c, kCGTextStroke);
    // 描边颜色
    self.textColor = [UIColor redColor];
    [super drawTextInRect:rect];
    // 文本颜色
    self.textColor = [UIColor yellowColor];
    CGContextSetTextDrawingMode(c, kCGTextFill);
    [super drawTextInRect:rect];
}

28、UIView背景颜色渐变

    UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 100)];
    [self.view addSubview:view];
    CAGradientLayer *gradient = [CAGradientLayer layer];
    gradient.frame = view.bounds;
    gradient.colors = [NSArray arrayWithObjects:(id)[[UIColor blackColor] CGColor], (id)[[UIColor whiteColor] CGColor], nil];
    [view.layer insertSublayer:gradient atIndex:0];

29、UITextView中打开或禁用复制，剪切，选择，全选等功能

// 继承UITextView重写这个方法
- (BOOL)canPerformAction:(SEL)action withSender:(id)sender
{
// 返回NO为禁用，YES为开启
    // 粘贴
    if (action == @selector(paste:)) return NO;
    // 剪切
    if (action == @selector(cut:)) return NO;
    // 复制
    if (action == @selector(copy:)) return NO;
    // 选择
    if (action == @selector(select:)) return NO;
    // 选中全部
    if (action == @selector(selectAll:)) return NO;
    // 删除
    if (action == @selector(delete:)) return NO;
    // 分享
    if (action == @selector(share)) return NO;
    return [super canPerformAction:action withSender:sender];
}