1脯丝、禁止手機(jī)睡眠

[UIApplication sharedApplication].idleTimerDisabled = YES;

2寄纵、隱藏某行cell

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath

{

// 如果是你需要隱藏的那一行翻擒，返回高度為0

??? if(indexPath.row == YouWantToHideRow)

??????? return 0;

??? return 44;

}

// 然后再你需要隱藏cell的時候調(diào)用

[self.tableView beginUpdates];

[self.tableView endUpdates];

3矛双、禁用button高亮

button.adjustsImageWhenHighlighted = NO;

或者在創(chuàng)建的時候

UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];

4敬辣、tableview遇到這種報錯failed to obtain a cell from its dataSource

是因?yàn)槟愕腸ell被調(diào)用的早了雪标。先循環(huán)使用了cell，后又創(chuàng)建cell溉跃。順序錯了

可能原因：1村刨、xib的cell沒有注冊 2、內(nèi)存中已經(jīng)有這個cell的緩存了(也就是說通過你的cellId找到的cell并不是你想要的類型)撰茎，這時候需要改下cell的標(biāo)識

5嵌牺、cocoa pods報這個錯誤：unable to access 'https://github.com/facebook/pop.git/': Operation timed out after 0 milliseconds with 0 out of 0 bytes received

解決辦法：原因可能是網(wǎng)絡(luò)問題，網(wǎng)絡(luò)請求超時了龄糊，只需要重試就行了

6逆粹、cocoa pods 出現(xiàn)ERROR: While executing gem ... (Errno::EPERM)

解決辦法：

https://segmentfault.com/q/1010000002926243

7、動畫切換window的根控制器

// options是動畫選項(xiàng)

[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) {

??? }];

8绎签、去除數(shù)組中重復(fù)的對象

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

9枯饿、編譯的時候遇到?no such file or directory: ／users／apple／XXX

是因?yàn)榫幾g的時候，在此路徑下找不到這個文件诡必，解決這個問題奢方，首先是是要檢查缺少的文件是不是在工程中，如果不在工程中爸舒，需要從本地拖進(jìn)去蟋字，如果發(fā)現(xiàn)已經(jīng)存在工程中了，或者拖進(jìn)去還是報錯扭勉，這時候需要去build phases中搜索這個文件鹊奖，這時候很可能會搜出現(xiàn)兩個相同的文件，這時候涂炎，有一個路徑是正確的忠聚，刪除另外一個即可。如果刪除了還是不行唱捣，需要把兩個都刪掉两蟀，然后重新往工程里拖進(jìn)這個文件即可

build phases

10、iOS8系統(tǒng)中震缭，tableView最好實(shí)現(xiàn)下-tableView: heightForRowAtIndexPath:這個代理方法赂毯，要不然在iOS8中可能就會出現(xiàn)顯示不全或者無法響應(yīng)事件的問題

11、iOS8中實(shí)現(xiàn)側(cè)滑功能的時候這個方法必須實(shí)現(xiàn)，要不然在iOS8中無法側(cè)滑

// 必須寫的方法党涕，和editActionsForRowAtIndexPath配對使用烦感，里面什么不寫也行

- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {

}

12、三個通知

NSSystemTimeZoneDidChangeNotification監(jiān)聽修改時間界面的兩個按鈕狀態(tài)變化

UIApplicationSignificantTimeChangeNotification 監(jiān)聽用戶改變時間 （只要點(diǎn)擊自動設(shè)置按鈕就會調(diào)用）

?NSSystemClockDidChangeNotification 監(jiān)聽用戶修改時間（時間不同才會調(diào)用）

13膛堤、SDWebImage本地緩存有時候會害人手趣。如果之前緩存過一張圖片，即使下次服務(wù)器換了這張圖片骑祟，但是圖片url沒換回懦，用sdwebimage下載下來的還是以前那張,所以遇到這種問題，不要先去懟服務(wù)器次企，清空下緩存再試就好了怯晕。

或者更換SDWebImage本地緩存

? ? ? ? ? ? [[SDWebImageManager sharedManager].imageCache storeImage:image forKey:imageStr toDisk:YES completion:nil];

14、上線前注意：

1）缸棵、刪掉代碼中所有的測試代碼

2）舟茶、如果后臺有審核模式，提醒后臺開啟此模式

3）堵第、主流程再跑一跑

4）吧凉、全局搜索waring，檢查所有標(biāo)記waring的地方

15踏志、跳進(jìn)app權(quán)限設(shè)置

// 跳進(jìn)app設(shè)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];

??????????????? }

??????????? }

16阀捅、給一個view截圖

UIGraphicsBeginImageContextWithOptions(view.bounds.size, YES, 0.0);

??? [view.layer renderInContext:UIGraphicsGetCurrentContext()];

??? UIImage *img = UIGraphicsGetImageFromCurrentImageContext();

??? UIGraphicsEndImageContext();

17、開發(fā)中如果要動態(tài)修改tableView的tableHeaderView或者tableFooterView的高度针余，需要給tableView重新設(shè)置饲鄙，而不是直接更改高度。正確的做法是重新設(shè)置一下tableView.tableFooterView = 更改過高度的view圆雁。為什么忍级？其實(shí)在iOS8以上直接改高度是沒有問題的，在iOS8中出現(xiàn)了contentSize不準(zhǔn)確的問題伪朽，這是解決辦法轴咱。

18、注意對象為nil的時候烈涮，調(diào)用此對象分類的方法不會執(zhí)行

19朴肺、collectionView的內(nèi)容小于其寬高的時候是不能滾動的，設(shè)置可以滾動：

collectionView.alwaysBounceHorizontal = YES;

collectionView.alwaysBounceVertical = YES;

20坚洽、設(shè)置navigationBar上的title顏色和大小

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

21宇挫、顏色轉(zhuǎn)圖片

+ (UIImage *)cl_imageWithColor:(UIColor *)color {

? CGRect rect = CGRectMake(0.0f, 0.0f, 1.0f, 1.0f);

? UIGraphicsBeginImageContext(rect.size);

? CGContextRef context = UIGraphicsGetCurrentContext();

? CGContextSetFillColorWithColor(context, [color CGColor]);

? CGContextFillRect(context, rect);

? UIImage *image = UIGraphicsGetImageFromCurrentImageContext();

? UIGraphicsEndImageContext();

? return image;

}

22、view設(shè)置圓角

#define ViewBorderRadius(View, Radius, Width, Color)\

\

[View.layer setCornerRadius:(Radius)];\

[View.layer setMasksToBounds:YES];\

[View.layer setBorderWidth:(Width)];\

[View.layer setBorderColor:[Color CGColor]] // view圓角

23酪术、強(qiáng)／弱引用

#define WeakSelf(type)? __weak typeof(type) weak##type = type; // weak

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

24、由角度轉(zhuǎn)換弧度

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

25、由弧度轉(zhuǎn)換角度

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

26绘雁、獲取圖片資源

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

27橡疼、獲取temp

#define PathTemp NSTemporaryDirectory()

28、獲取沙盒 Document

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

29庐舟、獲取沙盒 Cache

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

30欣除、GCD代碼只執(zhí)行一次

#define kDISPATCH_ONCE_BLOCK(onceBlock) static dispatch_once_t onceToken; dispatch_once(&onceToken, onceBlock);

31、自定義NSLog

#ifdef DEBUG

#define NSLog(fmt, ...) NSLog((@"%s [Line %d] " fmt), __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__)

#else

#define NSLog(...)

#endif

32挪略、Font

#define FontL(s)???????????? [UIFont systemFontOfSize:s weight:UIFontWeightLight]

#define FontR(s)???????????? [UIFont systemFontOfSize:s weight:UIFontWeightRegular]

#define FontB(s)???????????? [UIFont systemFontOfSize:s weight:UIFontWeightBold]

#define FontT(s)???????????? [UIFont systemFontOfSize:s weight:UIFontWeightThin]

#define Font(s)????????????? FontL(s)

33历帚、FORMAT

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

34、在主線程上運(yùn)行

#define kDISPATCH_MAIN_THREAD(mainQueueBlock) dispatch_async(dispatch_get_main_queue(), mainQueueBlock);

35杠娱、開啟異步線程

#define kDISPATCH_GLOBAL_QUEUE_DEFAULT(globalQueueBlock) dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), globalQueueBlocl);

36挽牢、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]

37、隨機(jī)顏色

+ (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;

}

//rgb

#define RGBCOLOR(r,g,b) [UIColor colorWithRed:(r)/255.0green:(g)/255.0blue:(b)/255.0alpha:1]

#define RGBACOLOR(r,g,b,a) [UIColor colorWithRed:(r)/255.0green:(g)/255.0blue:(b)/255.0alpha:(a)]

//16進(jìn)制顏色

#define UIColorFromRGB(rgbValue) [UIColor colorWithRed:((float)((rgbValue &0xFF0000) >>16))/255.0green:((float)((rgbValue &0xFF00) >>8))/255.0blue:((float)(rgbValue &0xFF))/255.0alpha:1.0]

//隨機(jī)色

#define RANDOMCOLOR [UIColor colorWithRed:(arc4random() %256/255.0) green:(arc4random() %256/255.0) blue:(arc4random() %256/255.0) alpha:1]

38摊求、獲取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;

}

39禽拔、修改textField的placeholder的字體顏色、大小

[textField setValue:[UIColor redColor] forKeyPath:@"_placeholderLabel.textColor"];

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

40室叉、統(tǒng)一收起鍵盤

?? [self.view endEditing:YES];

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

41睹栖、控制屏幕旋轉(zhuǎn)，在控制器中寫

/** 是否支持自動轉(zhuǎn)屏 */

- (BOOL)shouldAutorotate {

??? return YES;

}

/** 支持哪些屏幕方向 */

- (UIInterfaceOrientationMask)supportedInterfaceOrientations {

??? return UIInterfaceOrientationMaskLandscapeLeft | UIInterfaceOrientationMaskLandscapeRight;

}

/** 默認(rèn)的屏幕方向（當(dāng)前ViewController必須是通過模態(tài)出來的UIViewController（模態(tài)帶導(dǎo)航的無效）方式展現(xiàn)出來的茧痕，才會調(diào)用這個方法） */

- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation {

??? return UIInterfaceOrientationLandscapeLeft | UIInterfaceOrientationLandscapeRight;

}

42野来、獲取app緩存大小

- (CGFloat)getCachSize {

??? NSUInteger imageCacheSize = [[SDImageCache sharedImageCache] getSize];

??? //獲取自定義緩存大小

??? //用枚舉器遍歷 一個文件夾的內(nèi)容

??? //1.獲取 文件夾枚舉器

??? NSString *myCachePath = [NSHomeDirectory() stringByAppendingPathComponent:@"Library/Caches"];

??? NSDirectoryEnumerator *enumerator = [[NSFileManager defaultManager] enumeratorAtPath:myCachePath];

??? __block NSUInteger count = 0;

??? //2.遍歷

??? for (NSString *fileName in enumerator) {

??????? NSString *path = [myCachePath stringByAppendingPathComponent:fileName];

??????? NSDictionary *fileDict = [[NSFileManager defaultManager] attributesOfItemAtPath:path error:nil];

??????? count += fileDict.fileSize;//自定義所有緩存大小

??? }

??? // 得到是字節(jié)? 轉(zhuǎn)化為M

??? CGFloat totalSize = ((CGFloat)imageCacheSize+count)/1024/1024;

??? return totalSize;

}

43、清理app緩存

- (void)handleClearView {

??? //刪除兩部分

??? //1.刪除 sd 圖片緩存

??? //先清除內(nèi)存中的圖片緩存

??? [[SDImageCache sharedImageCache] clearMemory];

??? //清除磁盤的緩存

??? [[SDImageCache sharedImageCache] clearDisk];

??? //2.刪除自己緩存

??? NSString *myCachePath = [NSHomeDirectory() stringByAppendingPathComponent:@"Library/Caches"];

??? [[NSFileManager defaultManager] removeItemAtPath:myCachePath error:nil];

}

44踪旷、模型轉(zhuǎn)字典

static NSSet *classes;

- (NSMutableDictionary *)getParameterDictionary {

??? NSMutableDictionary *dict = [NSMutableDictionary dictionary];

??? Class c = self.class;

??? while (c) {

??????? unsigned count;

??????? objc_property_t *properties = class_copyPropertyList([c class], &count);

??????? for (int i = 0; i < count; i++) {

??????????? NSString *key = [NSString stringWithUTF8String:property_getName(properties[i])];

??????????? dict[key] = [self valueForKey:key];

??????? }

??????? free(properties);

??????? // 獲得父類

??????? c = class_getSuperclass(c);

??????? if ([self isClassFromFoundation:c]) break;

??? }

??? return dict;

}

- (BOOL)isClassFromFoundation:(Class)c

{

??? if (c == [NSObject class] || c == [NSManagedObject class]) return YES;

??? __block BOOL result = NO;

??? [[self foundationClasses] enumerateObjectsUsingBlock:^(Class foundationClass, BOOL *stop) {

??????? if ([c isSubclassOfClass:foundationClass]) {

??????????? result = YES;

??????????? *stop = YES;

??????? }

??? }];

??? return result;

}

- (NSSet *)foundationClasses

{

??? if (classes == nil) {

??????? // 集合中沒有NSObject曼氛，因?yàn)閹缀跛械念惗际抢^承自NSObject，具體是不是NSObject需要特殊判斷

??????? classes = [NSSet setWithObjects:

????????????????????????????? [NSURL class],

????????????????????????????? [NSDate class],

????????????????????????????? [NSValue class],

????????????????????????????? [NSData class],

????????????????????????????? [NSError class],

????????????????????????????? [NSArray class],

????????????????????????????? [NSDictionary class],

????????????????????????????? [NSString class],

????????????????????????????? [NSAttributedString class], nil];

??? }

??? return classes;

}

45埃脏、交換兩個方法實(shí)現(xiàn)

Class aClass = [self class];

??????? SEL originalSelector = @selector(viewWillAppear:);

??????? SEL swizzledSelector = @selector(xxx_viewWillAppear:);

??????? Method originalMethod = class_getInstanceMethod(aClass, originalSelector);

??????? Method swizzledMethod = class_getInstanceMethod(aClass, swizzledSelector);

??????? BOOL didAddMethod =

??????????? class_addMethod(aClass,

??????????????? originalSelector,

??????????????? method_getImplementation(swizzledMethod),

??????????????? method_getTypeEncoding(swizzledMethod));

??????? if (didAddMethod) {

??????????? class_replaceMethod(aClass,

??????????????? swizzledSelector,

??????????????? method_getImplementation(originalMethod),

??????????????? method_getTypeEncoding(originalMethod));

??????? } else {

??????????? method_exchangeImplementations(originalMethod, swizzledMethod);

??????? }

46搪锣、打印百分號和引號

??? NSLog(@"%%");

??? NSLog(@"\"");

47、幾個常用權(quán)限判斷

??? if ([CLLocationManager authorizationStatus] ==kCLAuthorizationStatusDenied) {

??????? NSLog(@"沒有定位權(quán)限");

??? }

??? AVAuthorizationStatus statusVideo = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo];

??? if (statusVideo == AVAuthorizationStatusDenied) {

??????? NSLog(@"沒有攝像頭權(quán)限");

??? }

??? //是否有麥克風(fēng)權(quán)限

??? AVAuthorizationStatus statusAudio = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeAudio];

??? if (statusAudio == AVAuthorizationStatusDenied) {

??????? NSLog(@"沒有錄音權(quán)限");

??? }

??? [PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {

??????? if (status == PHAuthorizationStatusDenied) {

??????????? NSLog(@"沒有相冊權(quán)限");

??????? }

??? }];

48彩掐、獲取手機(jī)型號

??? + (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";

??? // 日行兩款手機(jī)型號均為日本獨(dú)占构舟，可能使用索尼FeliCa支付方案而不是蘋果支付

??? if ([platform isEqualToString:@"iPhone9,1"])??? return @"國行、日版堵幽、港行iPhone 7";

??? if ([platform isEqualToString:@"iPhone9,2"])??? return @"港行狗超、國行iPhone 7 Plus";

??? if ([platform isEqualToString:@"iPhone9,3"])??? return @"美版、臺版iPhone 7";

??? if ([platform isEqualToString:@"iPhone9,4"])??? return @"美版朴下、臺版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;

}

49努咐、長按復(fù)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 = @"需要復(fù)制的文本";

??? }

}

50、cocoapods升級

在終端執(zhí)行 sudo gem install -n / usr / local / bin cocoapods --pre

51殴胧、設(shè)置啟動頁后渗稍，依然顯示之前的

刪除app佩迟，手機(jī)重啟，重新安裝

52竿屹、判斷圖片類型

//通過圖片Data數(shù)據(jù)第一個字節(jié) 來獲取圖片擴(kuò)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;

}

53报强、獲取手機(jī)和app信息

NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];?

CFShow(infoDictionary);?

// app名稱?

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"];?

//手機(jī)序列號?

??? NSString* identifierNumber = [[UIDevice currentDevice] uniqueIdentifier];?

NSLog(@"手機(jī)序列號: %@",identifierNumber);?

//手機(jī)別名： 用戶定義的名稱?

??? NSString* userPhoneName = [[UIDevice currentDevice] name];?

NSLog(@"手機(jī)別名: %@", userPhoneName);?

//設(shè)備名稱?

??? NSString* deviceName = [[UIDevice currentDevice] systemName];?

NSLog(@"設(shè)備名稱: %@",deviceName );?

//手機(jī)系統(tǒng)版本?

??? NSString* phoneVersion = [[UIDevice currentDevice] systemVersion];?

NSLog(@"手機(jī)系統(tǒng)版本: %@", phoneVersion);?

//手機(jī)型號?

??? NSString* phoneModel = [[UIDevice currentDevice] model];?

NSLog(@"手機(jī)型號: %@",phoneModel );?

//地方型號? （國際化區(qū)域名稱）?

??? NSString* localPhoneModel = [[UIDevice currentDevice] localizedModel];?

NSLog(@"國際化區(qū)域名稱: %@",localPhoneModel );?

??? NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];?

// 當(dāng)前應(yīng)用名稱?

??? NSString *appCurName = [infoDictionary objectForKey:@"CFBundleDisplayName"];?

NSLog(@"當(dāng)前應(yīng)用名稱：%@",appCurName);?

// 當(dāng)前應(yīng)用軟件版本? 比如：1.0.1?

??? NSString *appCurVersion = [infoDictionary objectForKey:@"CFBundleShortVersionString"];?

NSLog(@"當(dāng)前應(yīng)用軟件版本:%@",appCurVersion);?

// 當(dāng)前應(yīng)用版本號碼?? int類型?

??? NSString *appCurVersionNum = [infoDictionary objectForKey:@"CFBundleVersion"];?

??? NSLog(@"當(dāng)前應(yīng)用版本號碼：%@",appCurVersionNum);

54、獲取一個類的所有屬性

id LenderClass = objc_getClass("Lender");

unsigned int outCount, i;

objc_property_t *properties = class_copyPropertyList(LenderClass, &outCount);

for (i = 0; i < outCount; i++) {

??? objc_property_t property = properties[i];

??? fprintf(stdout, "%s %s\n", property_getName(property), property_getAttributes(property));

}

55拱燃、image圓角

- (UIImage *)circleImage

{

??? // NO代表透明

??? UIGraphicsBeginImageContextWithOptions(self.size, NO, 1);

??? // 獲得上下文

??? CGContextRef ctx = UIGraphicsGetCurrentContext();

??? // 添加一個圓

??? CGRect rect = CGRectMake(0, 0, self.size.width, self.size.height);

??? // 方形變圓形

??? CGContextAddEllipseInRect(ctx, rect);

??? // 裁剪

??? CGContextClip(ctx);

??? // 將圖片畫上去

??? [self drawInRect:rect];

??? UIImage *image = UIGraphicsGetImageFromCurrentImageContext();

??? UIGraphicsEndImageContext();

??? return image;

}

56秉溉、image拉伸

+ (UIImage *)resizableImage:(NSString *)imageName

{

??? UIImage *image = [UIImage imageNamed:imageName];

??? CGFloat imageW = image.size.width;

??? CGFloat imageH = image.size.height;

??? return [image resizableImageWithCapInsets:UIEdgeInsetsMake(imageH * 0.5, imageW * 0.5, imageH * 0.5, imageW * 0.5) resizingMode:UIImageResizingModeStretch];

}

57、JSON字符串轉(zhuǎn)字典

+ (NSDictionary *)parseJSONStringToNSDictionary:(NSString *)JSONString {

??? NSData *JSONData = [JSONString dataUsingEncoding:NSUTF8StringEncoding];

??? NSDictionary *responseJSON = [NSJSONSerialization JSONObjectWithData:JSONData options:NSJSONReadingMutableLeaves error:nil];

??? return responseJSON;

}

58碗誉、身份證號驗(yàn)證

- (BOOL)validateIdentityCard {

??? BOOL flag;

??? if (self.length <= 0) {

??????? flag = NO;

??????? return flag;

??? }

??? NSString *regex2 = @"^(\\d{14}|\\d{17})(\\d|[xX])$";

??? NSPredicate *identityCardPredicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@",regex2];

??? return [identityCardPredicate evaluateWithObject:self];

}

59召嘶、獲取設(shè)備mac地址

+ (NSString *)macAddress {

??? int???????????????? mib[6];

??? size_t????????????? len;

??? char??????????????? *buf;

??? unsigned char?????? *ptr;

??? struct if_msghdr??? *ifm;

??? struct sockaddr_dl? *sdl;

??? mib[0] = CTL_NET;

??? mib[1] = AF_ROUTE;

??? mib[2] = 0;

??? mib[3] = AF_LINK;

??? mib[4] = NET_RT_IFLIST;

??? if((mib[5] = if_nametoindex("en0")) == 0) {

??????? printf("Error: if_nametoindex error\n");

??????? return NULL;

??? }

??? if(sysctl(mib, 6, NULL, &len, NULL, 0) < 0) {

??????? printf("Error: sysctl, take 1\n");

??????? return NULL;

??? }

??? if((buf = malloc(len)) == NULL) {

??????? printf("Could not allocate memory. Rrror!\n");

??????? return NULL;

??? }

??? if(sysctl(mib, 6, buf, &len, NULL, 0) < 0) {

??????? printf("Error: sysctl, take 2");

??????? return NULL;

??? }

??? ifm = (struct if_msghdr *)buf;

??? sdl = (struct sockaddr_dl *)(ifm + 1);

??? ptr = (unsigned char *)LLADDR(sdl);

??? NSString *outstring = [NSString stringWithFormat:@"%02X:%02X:%02X:%02X:%02X:%02X",

?????????????????????????? *ptr, *(ptr+1), *(ptr+2), *(ptr+3), *(ptr+4), *(ptr+5)];

??? free(buf);

??? return outstring;

}

60、導(dǎo)入自定義字體庫

1哮缺、找到你想用的字體的 ttf 格式弄跌，拖入工程

2、在工程的plist中增加一行數(shù)組蝴蜓，“Fonts provided by application”

3碟绑、為這個key添加一個item，value為你剛才導(dǎo)入的ttf文件名

4茎匠、直接使用即可：label.font = [UIFont fontWithName:@"你剛才導(dǎo)入的ttf文件名" size:20.0]格仲；

61、拿到當(dāng)前正在顯示的控制器诵冒，不管是push進(jìn)去的凯肋，還是present進(jìn)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;

??????? }

??? }

}

62、runtime為一個類動態(tài)添加屬性

// 動態(tài)添加屬性的本質(zhì)是: 讓對象的某個屬性與值產(chǎn)生關(guān)聯(lián)

??????? objc_setAssociatedObject(self, WZBPlaceholderViewKey, placeholderView, OBJC_ASSOCIATION_RETAIN_NONATOMIC);

63汽馋、獲取runtime為一個類動態(tài)添加的屬性

objc_getAssociatedObject(self, WZBPlaceholderViewKey);

64侮东、KVO監(jiān)聽某個對象的屬性

// 添加監(jiān)聽者

[self addObserver:self forKeyPath:property options:NSKeyValueObservingOptionNew context:nil];

// 當(dāng)監(jiān)聽的屬性值變化的時候會來到這個方法

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {

??? if ([keyPath isEqualToString:@"property"]) {

?????? [self textViewTextChange];

?????? } else {

???? }

}

65、Reachability判斷網(wǎng)絡(luò)狀態(tài)

NetworkStatus status = [[Reachability reachabilityForInternetConnection] currentReachabilityStatus];

??? if (status == NotReachable) {

??????? NSLog(@"當(dāng)前設(shè)備無網(wǎng)絡(luò)");

??? }

??? if (status == ReachableViaWiFi) {

??????? NSLog(@"當(dāng)前wifi網(wǎng)絡(luò)");

??? }

??? if (status == ReachableViaWWAN) {

??????? NSLog(@"當(dāng)前蜂窩移動網(wǎng)絡(luò)");

??? }

66豹芯、AFNetworking監(jiān)聽網(wǎng)絡(luò)狀態(tài)

// 監(jiān)聽網(wǎng)絡(luò)狀況

??? AFNetworkReachabilityManager *mgr = [AFNetworkReachabilityManager sharedManager];

??? [mgr setReachabilityStatusChangeBlock:^(AFNetworkReachabilityStatus status) {

??????? switch (status) {

??????????? case AFNetworkReachabilityStatusUnknown:

??????????????? break;

??????????? case AFNetworkReachabilityStatusNotReachable: {

??????????????? [SVProgressHUD showInfoWithStatus:@"當(dāng)前設(shè)備無網(wǎng)絡(luò)"];

??????????? }

??????????????? break;

??????????? case AFNetworkReachabilityStatusReachableViaWiFi:

??????????????? [SVProgressHUD showInfoWithStatus:@"當(dāng)前Wi-Fi網(wǎng)絡(luò)"];

??????????????? break;

??????????? case AFNetworkReachabilityStatusReachableViaWWAN:

??????????????? [SVProgressHUD showInfoWithStatus:@"當(dāng)前蜂窩移動網(wǎng)絡(luò)"];

??????????????? break;

??????????? default:

??????????????? break;

??????? }

??? }];

??? [mgr startMonitoring];

67悄雅、透明顏色不影響子視圖透明度

??? [UIColor colorWithRed:<#(CGFloat)#> green:<#(CGFloat)#> blue:<#(CGFloat)#> alpha:<#(CGFloat)#>];

68、取圖片某一點(diǎn)的顏色

??? if (point.x < 0 || point.y < 0) return nil;

??? CGImageRef imageRef = self.CGImage;

??? NSUInteger width = CGImageGetWidth(imageRef);

??? NSUInteger height = CGImageGetHeight(imageRef);

??? if (point.x >= width || point.y >= height) return nil;

??? unsigned char *rawData = malloc(height * width * 4);

??? if (!rawData) return nil;

??? CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();

??? NSUInteger bytesPerPixel = 4;

??? NSUInteger bytesPerRow = bytesPerPixel * width;

??? NSUInteger bitsPerComponent = 8;

??? CGContextRef context = CGBitmapContextCreate(rawData,

???????????????????????????????????????????????? width,

???????????????????????????????????????????????? height,

???????????????????????????????????????????????? bitsPerComponent,

???????????????????????????????????????????????? bytesPerRow,

???????????????????????????????????????????????? colorSpace,

???????????????????????????????????????????????? kCGImageAlphaPremultipliedLast

???????????????????????????????????????????????? | kCGBitmapByteOrder32Big);

??? if (!context) {

??????? free(rawData);

??????? return nil;

??? }

??? CGColorSpaceRelease(colorSpace);

??? CGContextDrawImage(context, CGRectMake(0, 0, width, height), imageRef);

??? CGContextRelease(context);

??? int byteIndex = (bytesPerRow * point.y) + point.x * bytesPerPixel;

??? CGFloat red?? = (rawData[byteIndex]???? * 1.0) / 255.0;

??? CGFloat green = (rawData[byteIndex + 1] * 1.0) / 255.0;

??? CGFloat blue? = (rawData[byteIndex + 2] * 1.0) / 255.0;

??? CGFloat alpha = (rawData[byteIndex + 3] * 1.0) / 255.0;

??? UIColor *result = nil;

??? result = [UIColor colorWithRed:red green:green blue:blue alpha:alpha];

??? free(rawData);

??? return result;

69铁蹈、判斷該圖片是否有透明度通道

? - (BOOL)hasAlphaChannel

{

??? CGImageAlphaInfo alpha = CGImageGetAlphaInfo(self.CGImage);

??? return (alpha == kCGImageAlphaFirst ||

??????????? alpha == kCGImageAlphaLast ||

??????????? alpha == kCGImageAlphaPremultipliedFirst ||

??????????? alpha == kCGImageAlphaPremultipliedLast);

}

70宽闲、獲得灰度圖

+ (UIImage*)covertToGrayImageFromImage:(UIImage*)sourceImage

{

??? int width = sourceImage.size.width;

??? int height = sourceImage.size.height;

??? CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceGray();

??? CGContextRef context = CGBitmapContextCreate (nil,width,height,8,0,colorSpace,kCGImageAlphaNone);

??? CGColorSpaceRelease(colorSpace);

??? if (context == NULL) {

??????? return nil;

??? }

??? CGContextDrawImage(context,CGRectMake(0, 0, width, height), sourceImage.CGImage);

??? CGImageRef contextRef = CGBitmapContextCreateImage(context);

??? UIImage *grayImage = [UIImage imageWithCGImage:contextRef];

??? CGContextRelease(context);

??? CGImageRelease(contextRef);

??? return grayImage;

}

71、根據(jù)bundle中的文件名讀取圖片

?? + (UIImage *)imageWithFileName:(NSString *)name {

??? NSString *extension = @"png";

??? NSArray *components = [name componentsSeparatedByString:@"."];

??? if ([components count] >= 2) {

??????? NSUInteger lastIndex = components.count - 1;

??????? extension = [components objectAtIndex:lastIndex];

??????? name = [name substringToIndex:(name.length-(extension.length+1))];

??? }

??? // 如果為Retina屏幕且存在對應(yīng)圖片握牧，則返回Retina圖片容诬，否則查找普通圖片

??? if ([UIScreen mainScreen].scale == 2.0) {

??????? name = [name stringByAppendingString:@"@2x"];

??????? NSString *path = [[NSBundle mainBundle] pathForResource:name ofType:extension];

??????? if (path != nil) {

??????????? return [UIImage imageWithContentsOfFile:path];

??????? }

??? }

??? if ([UIScreen mainScreen].scale == 3.0) {

??????? name = [name stringByAppendingString:@"@3x"];

??????? NSString *path = [[NSBundle mainBundle] pathForResource:name ofType:extension];

??????? if (path != nil) {

??????????? return [UIImage imageWithContentsOfFile:path];

??????? }

??? }

??? NSString *path = [[NSBundle mainBundle] pathForResource:name ofType:extension];

??? if (path) {

??????? return [UIImage imageWithContentsOfFile:path];

??? }

??? return nil;

}

72、合并兩個圖片

+ (UIImage*)mergeImage:(UIImage*)firstImage withImage:(UIImage*)secondImage {

??? CGImageRef firstImageRef = firstImage.CGImage;

??? CGFloat firstWidth = CGImageGetWidth(firstImageRef);

??? CGFloat firstHeight = CGImageGetHeight(firstImageRef);

??? CGImageRef secondImageRef = secondImage.CGImage;

??? CGFloat secondWidth = CGImageGetWidth(secondImageRef);

??? CGFloat secondHeight = CGImageGetHeight(secondImageRef);

??? CGSize mergedSize = CGSizeMake(MAX(firstWidth, secondWidth), MAX(firstHeight, secondHeight));

??? UIGraphicsBeginImageContext(mergedSize);

??? [firstImage drawInRect:CGRectMake(0, 0, firstWidth, firstHeight)];

??? [secondImage drawInRect:CGRectMake(0, 0, secondWidth, secondHeight)];

??? UIImage *image = UIGraphicsGetImageFromCurrentImageContext();

??? UIGraphicsEndImageContext();

??? return image;

}

73沿腰、根據(jù)bundle中的圖片名創(chuàng)建imageview

+ (id)imageViewWithImageNamed:(NSString*)imageName

{

??? return [[UIImageView alloc] initWithImage:[UIImage imageNamed:imageName]];

}

74览徒、為imageView添加倒影

??? CGRect frame = self.frame;

??? frame.origin.y += (frame.size.height + 1);

??? UIImageView *reflectionImageView = [[UIImageView alloc] initWithFrame:frame];

??? self.clipsToBounds = TRUE;

??? reflectionImageView.contentMode = self.contentMode;

??? [reflectionImageView setImage:self.image];

??? reflectionImageView.transform = CGAffineTransformMakeScale(1.0, -1.0);

??? CALayer *reflectionLayer = [reflectionImageView layer];

??? CAGradientLayer *gradientLayer = [CAGradientLayer layer];

??? gradientLayer.bounds = reflectionLayer.bounds;

??? gradientLayer.position = CGPointMake(reflectionLayer.bounds.size.width / 2, reflectionLayer.bounds.size.height * 0.5);

??? gradientLayer.colors = [NSArray arrayWithObjects:

??????????????????????????? (id)[[UIColor clearColor] CGColor],

??????????????????????????? (id)[[UIColor colorWithRed:1.0 green:1.0 blue:1.0 alpha:0.3] CGColor], nil];

??? gradientLayer.startPoint = CGPointMake(0.5,0.5);

??? gradientLayer.endPoint = CGPointMake(0.5,1.0);

??? reflectionLayer.mask = gradientLayer;

??? [self.superview addSubview:reflectionImageView];

75、畫水印

// 畫水印

- (void) setImage:(UIImage *)image withWaterMark:(UIImage *)mark inRect:(CGRect)rect

{

??? if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 4.0)

??? {

??????? UIGraphicsBeginImageContextWithOptions(self.frame.size, NO, 0.0);

??? }

??? //原圖

??? [image drawInRect:self.bounds];

??? //水印圖

??? [mark drawInRect:rect];

??? UIImage *newPic = UIGraphicsGetImageFromCurrentImageContext();

??? UIGraphicsEndImageContext();

??? self.image = newPic;

}

76颂龙、讓label的文字內(nèi)容顯示在左上／右上／左下／右下／中心頂／中心底部

自定義UILabel

// 重寫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];

}

77习蓬、scrollView上的輸入框纽什，鍵盤擋住的問題

推薦用IQKeyboardManager這個框架！

手動解決如下

1友雳、監(jiān)聽鍵盤彈出／消失的通知

2稿湿、在通知中加入代碼：

NSDictionary* info = [aNotification userInfo];

CGRect keyPadFrame=[[UIApplication sharedApplication].keyWindow convertRect:[[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue] fromView:self.view];

CGSize kbSize =keyPadFrame.size;

CGRect activeRect=[self.view convertRect:activeField.frame fromView:activeField.superview];

CGRect aRect = self.view.bounds;

aRect.size.height -= (kbSize.height);

CGPoint origin =? activeRect.origin;

origin.y -= backScrollView.contentOffset.y;

if (!CGRectContainsPoint(aRect, origin)) {

??? CGPoint scrollPoint = CGPointMake(0.0,CGRectGetMaxY(activeRect)-(aRect.size.height));

??? [backScrollView setContentOffset:scrollPoint animated:YES];

}

78、frame布局的cell動態(tài)高度

這種通常在你的模型中添加一個輔助屬性cellHeight押赊，在模型中重寫這個屬性的get方法，根據(jù)你的布局和模型中的其他屬性值計算出總高度包斑。最后在tableView：heightForRow方法中流礁，根據(jù)indexPath找出對應(yīng)的模型，返回這個高度即可罗丰。

79神帅、AutoLayout布局的cell動態(tài)高度

// 1、設(shè)置tableView的屬性

self.tableView.rowHeight = UITableViewAutomaticDimension;

self.tableView.estimatedRowHeight = 44.0; // 這個屬性非0萌抵，估計cell高度

// 2找御、至上而下設(shè)置cell的約束，注意绍填，上下左右最好都要頂?shù)絚ell的四周

cell

80霎桅、使用performSelector:調(diào)用函數(shù)，內(nèi)存泄漏問題

當(dāng)我們在開發(fā)中使用[obj performSelector:NSSelectorFromString(@"aMethod")];這類方法時可能會收到一個警告"performSelector may cause a leak because its selector is unknown".

是因?yàn)榫幾g器不清楚這個對象能不能相應(yīng)這個方法讨永，如果不能滔驶，則是不安全的，而且編譯器也不清楚該怎么處理這個方法的返回值卿闹！

使用以下代碼調(diào)用即可：

if (! obj) { return; }

SEL selector = NSSelectorFromString(@"aMethod");

IMP imp = [obj methodForSelector:selector];

void (*func)(id, SEL) = (void *)imp;

func(obj, selector);

或者：

SEL selector = NSSelectorFromString(@"aMethod");

((void (*)(id, SEL))[obj methodForSelector:selector])(obj, selector);

81揭糕、一個字符串是否包含另一個字符串

// 方法1

if ([str1 containsString:str2]) {

??????? NSLog(@"str1包含str2");

??? } else {

??????? NSLog(@"str1不包含str2");

??? }

// 方法2

if ([str1 rangeOfString: str2].location == NSNotFound) {

??????? NSLog(@"str1不包含str2");

??? } else {

??????? NSLog(@"str1包含str2");

??? }

82、cell去除選中效果

cell.selectionStyle = UITableViewCellSelectionStyleNone;

83锻霎、cell點(diǎn)按效果

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {

??? [tableView deselectRowAtIndexPath:indexPath animated:YES];

}

84著角、當(dāng)刪除一個從xib拖出來的屬性時，一定記得把xib中對應(yīng)的線也刪掉旋恼，不然會報類似[ setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key的crash

點(diǎn)擊這個叉號刪除

85吏口、真機(jī)測試的時候報錯：Could not launch "你的 App"，process launch failed: Security

因?yàn)槟愕腶pp沒有上線蚌铜，iOS9開始锨侯，需要手動信任Xcode生成的描述文件，打開手機(jī)設(shè)置->通用->描述文件->點(diǎn)擊你的app的描述文件->點(diǎn)擊信任

86冬殃、真機(jī)測試的時候報錯：Could not find Developer Disk Image

這是因?yàn)槟愕脑O(shè)備系統(tǒng)版本大于Xcode能兼容的系統(tǒng)版本囚痴，比如你的設(shè)備是iOS10.3，而Xcode版本是8.2（Xcode8.2最大兼容iOS10.2）审葬，就會報這個錯誤深滚。解決辦法就是升級Xcode奕谭！

87、UITextView沒有placeholder的問題痴荐？

網(wǎng)上有很多此類自定義控件血柳，也可以參考下我寫的一個UITextView分類?UITextView-WZB

88、移除字符串中的空格和換行

+ (NSString *)removeSpaceAndNewline:(NSString *)str {

??? NSString *temp = [str stringByReplacingOccurrencesOfString:@" " withString:@""];

??? temp = [temp stringByReplacingOccurrencesOfString:@"\r" withString:@""];

??? temp = [temp stringByReplacingOccurrencesOfString:@"\n" withString:@""];

??? return temp;

}

89生兆、判斷字符串中是否有空格

+ (BOOL)isBlank:(NSString *)str {

??? NSRange _range = [str rangeOfString:@" "];

??? if (_range.location != NSNotFound) {

??????? //有空格

??????? return YES;

??? } else {

??????? //沒有空格

??????? return NO;

??? }

}

90难捌、獲取一個視頻的第一幀圖片

??? NSURL *url = [NSURL URLWithString:filepath];

??? AVURLAsset *asset1 = [[AVURLAsset alloc] initWithURL:url options:nil];

??? AVAssetImageGenerator *generate1 = [[AVAssetImageGenerator alloc] initWithAsset:asset1];

??? generate1.appliesPreferredTrackTransform = YES;

??? NSError *err = NULL;

??? CMTime time = CMTimeMake(1, 2);

??? CGImageRef oneRef = [generate1 copyCGImageAtTime:time actualTime:NULL error:&err];

??? UIImage *one = [[UIImage alloc] initWithCGImage:oneRef];

??? return one;

91、獲取視頻的時長

+ (NSInteger)getVideoTimeByUrlString:(NSString *)urlString {

??? NSURL *videoUrl = [NSURL URLWithString:urlString];

??? AVURLAsset *avUrl = [AVURLAsset assetWithURL:videoUrl];

??? CMTime time = [avUrl duration];

??? int seconds = ceil(time.value/time.timescale);

??? return seconds;

}

92鸦难、字符串是否為空

+ (BOOL)isEqualToNil:(NSString *)str {

??? return str.length <= 0 || [str isEqualToString:@""] || !str;

}

93根吁、將app上傳到App Store的時候通常會遇到這個問題

try again

很多人說這事蘋果爸爸服務(wù)器問題，重復(fù)嘗試幾次合蔽，總會成功的击敌！

但是經(jīng)過嘗試發(fā)現(xiàn)如果使用Application Loader上傳成功率就非常高，所以還是推薦把ipa文件導(dǎo)出直接用Application Loader上傳拴事。

如果Application Loader也不行沃斤，需要檢查下自己的網(wǎng)絡(luò)，有時候vpn也會提高速度刃宵。

94衡瓶、當(dāng)tableView占不滿一屏?xí)r，去除下邊多余的單元格

self.tableView.tableHeaderView = [UIView new];

self.tableView.tableFooterView = [UIView new];

95组去、isKindOfClass和isMemberOfClass的區(qū)別

isKindOfClass可以判斷某個對象是否屬于某個類鞍陨，或者這個類的子類。

isMemberOfClass更加精準(zhǔn)从隆，它只能判斷這個對象類型是否為這個類(不能判斷子類)

96诚撵、__block

當(dāng)一個局部變量需要在block里改變時，需要在定義時加上__block修飾键闺，具體請看官方文檔?http://developer.apple.com/library/ios/documentation/cocoa/Conceptual/Blocks/Articles/bxVariables.html#//apple_ref/doc/uid/TP40007502-CH6-SW6

97寿烟、-[ViewController aMethod:]: unrecognized selector sent to instance 0x7fe91e607fb0

這是一個經(jīng)典錯誤，ViewController不能響應(yīng)aMethod這個方法辛燥，錯誤原因可能viewController文件中沒有實(shí)現(xiàn)aMethod這個方法

98筛武、UITableView () failed to obtain a cell from its dataSource ()

這個錯誤原因是tableView的代理方法-tableView:cellForRowAtIndexPath:需要返回一個UITableViewCell,而你返回了一個nil。另外這個地方返回值不是UITableViewCell類型也會導(dǎo)致崩潰

99挎塌、約束如何做UIView動畫徘六？

1、把需要改的約束Constraint拖條線出來榴都，成為屬性

2待锈、在需要動畫的地方加入代碼，改變此屬性的constant屬性

3嘴高、開始做UIView動畫竿音，動畫里邊調(diào)用layoutIfNeeded方法

@property (weak, nonatomic) IBOutlet NSLayoutConstraint *buttonTopConstraint;

self.buttonTopConstraint.constant = 100;

??? [UIView animateWithDuration:.5 animations:^{

??????? [self.view layoutIfNeeded];

??? }];

100和屎、從NSURL中拿到鏈接字符串

NSString *urlString = myURL.absoluteString;

101、將tableView滾動到頂部

[tableView setContentOffset:CGPointZero animated:YES];

或者

[tableView scrollRectToVisible:CGRectMake(0, 0, 1, 1) animated:YES];

102春瞬、如果用addTarget:action:forControlEvents:方法為一個button添加了很多點(diǎn)擊事件柴信，在某個時刻想一次刪除怎么辦？只需要調(diào)用下邊這句代碼

[youButton removeTarget:nil action:nil forControlEvents:UIControlEventAllEvents];

103宽气、某個字體的高度

font.lineHeight;

104随常、刪除某個view所有的子視圖

[[someView subviews]

makeObjectsPerformSelector:@selector(removeFromSuperview)];

105、刪除NSUserDefaults所有記錄

//方法一

? NSString *appDomain = [[NSBundle mainBundle] bundleIdentifier];

[[NSUserDefaults standardUserDefaults] removePersistentDomainForName:appDomain];??

//方法二?

- (void)resetDefaults {??

? NSUserDefaults * defs = [NSUserDefaults standardUserDefaults];

???? NSDictionary * dict = [defs dictionaryRepresentation];

???? for (id key in dict) {

????????? [defs removeObjectForKey:key];

???? }

????? [defs synchronize];

}

// 方法三

[[NSUserDefaults standardUserDefaults] setPersistentDomain:[NSDictionary dictionary] forName:[[NSBundle mainBundle] bundleIdentifier]];

106抹竹、禁用系統(tǒng)滑動返回功能

- (void)viewDidAppear:(BOOL)animated

{

???? [super viewDidAppear:animated];

if ([self.navigationController respondsToSelector:@selector(interactivePopGestureRecognizer)]) {self.navigationController.interactivePopGestureRecognizer.delegate = self;

??? }

}

- (void)viewWillDisappear:(BOOL)animated {

??? [super viewWillDisappear:animated];

??? if ([self.navigationController respondsToSelector:@selector(interactivePopGestureRecognizer)]) {self.navigationController.interactivePopGestureRecognizer.delegate = nil;

??? }

}

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer

{

???? return NO;

}

107线罕、模擬器報錯

模擬器報錯

解決辦法：

打開模擬器->Simulator->Reset Content and Settings...

如果不行，就重啟試試窃判！

108、自定義cell選中背景顏色

UIView *bgColorView = [[UIView alloc] init];

bgColorView.backgroundColor = [UIColor redColor];

[cell setSelectedBackgroundView:bgColorView];

109喇闸、UILabel設(shè)置內(nèi)邊距

子類化UILabel袄琳，重寫drawTextInRect方法

- (void)drawTextInRect:(CGRect)rect {

??? // 邊距，上左下右

??? UIEdgeInsets insets = {0, 5, 0, 5};

??? [super drawTextInRect:UIEdgeInsetsInsetRect(rect, insets)];

}

110燃乍、UILabel設(shè)置文字描邊

子類化UILabel唆樊，重寫drawTextInRect方法

- (void)drawTextInRect:(CGRect)rect

{

??? CGContextRef c = UIGraphicsGetCurrentContext();

??? // 設(shè)置描邊寬度

??? CGContextSetLineWidth(c, 1);

??? CGContextSetLineJoin(c, kCGLineJoinRound);

??? CGContextSetTextDrawingMode(c, kCGTextStroke);

??? // 描邊顏色

??? self.textColor = [UIColor redColor];

??? [super drawTextInRect:rect];

??? // 文本顏色

??? self.textColor = [UIColor yellowColor];

??? CGContextSetTextDrawingMode(c, kCGTextFill);

??? [super drawTextInRect:rect];

}

111、使用模擬器截圖

快捷鍵command + s

或者File->Save Screen Shot

112刻蟹、scrollView滾動到最下邊

CGPoint bottomOffset = CGPointMake(0, scrollView.contentSize.height - scrollView.bounds.size.height);

[scrollView setContentOffset:bottomOffset animated:YES];

113逗旁、UIView背景顏色漸變

??? 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];

114、停止UIView動畫

[yourView.layer removeAllAnimations]

115舆瘪、為UIView某個角添加圓角

// 左上角和右下角添加圓角

UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:view.bounds byRoundingCorners:(UIRectCornerTopLeft | UIRectCornerBottomRight) cornerRadii:CGSizeMake(20, 20)];

??? CAShapeLayer *maskLayer = [CAShapeLayer layer];

??? maskLayer.frame = view.bounds;

??? maskLayer.path = maskPath.CGPath;

??? view.layer.mask = maskLayer;

116片效、刪除Xcode Derived data緩存數(shù)據(jù)

依次點(diǎn)擊Xcode -> Preferences -> location，然后點(diǎn)擊 Derived data路徑后到小箭頭英古，刪除這個文件夾下的數(shù)據(jù)就可以了淀衣，如圖

Xcode Derived data

117、將一個view放置在其兄弟視圖的最上面

[parentView bringSubviewToFront:yourView]

118召调、將一個view放置在其兄弟視圖的最下面

[parentView sendSubviewToBack:yourView]

119膨桥、讓手機(jī)震動一下

倒入框架

#import

AudioServicesPlayAlertSound(kSystemSoundID_Vibrate);

或者

AudioServicesPlaySystemSound(kSystemSoundID_Vibrate);

120、layoutSubviews方法什么時候調(diào)用唠叛？

1只嚣、init方法不會調(diào)用

2、addSubview方法等時候會調(diào)用

3艺沼、bounds改變的時候調(diào)用

4册舞、scrollView滾動的時候會調(diào)用scrollView的layoutSubviews方法(所以不建議在scrollView的layoutSubviews方法中做復(fù)雜邏輯)

5、旋轉(zhuǎn)設(shè)備的時候調(diào)用

6澳厢、子視圖被移除的時候調(diào)用

參考請看：http://blog.logichigh.com/2011/03/16/when-does-layoutsubviews-get-called/

121环础、讓UILabel在指定的地方換行

// 換行符為\n,在需要換行的地方加上這個符號即可囚似，如?

label.numberOfLines = 0;

label.text = @"此處\n換行";

122、搖一搖功能

1线得、打開搖一搖功能

??? [UIApplication sharedApplication].applicationSupportsShakeToEdit = YES;

2饶唤、讓需要搖動的控制器成為第一響應(yīng)者

[self becomeFirstResponder];

3、實(shí)現(xiàn)以下方法

// 開始搖動

- (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event

// 取消搖動

- (void)motionCancelled:(UIEventSubtype)motion withEvent:(UIEvent *)event

// 搖動結(jié)束

- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event

123贯钩、獲取圖片大小

CGFloat imageWidth = image.size.width;

??? CGFloat imageHeight = imageWidth * image.scale;

124募狂、獲取view的坐標(biāo)在整個window上的位置

// v上的(0, 0)點(diǎn)在toView上的位置

CGPoint point = [v convertPoint:CGPointMake(0, 0) toView:[UIApplication sharedApplication].windows.lastObject];

或者

CGPoint point = [v.superview convertPoint:v.frame.origin toView:[UIApplication sharedApplication].windows.lastObject];

125、提交App Store審核程序限制

您的應(yīng)用程序的未壓縮大小必須小于4GB角雷。每個Mach-O可執(zhí)行文件（例如app_name.app/app_name）不能超過這些限制：

對于MinimumOSVersion小于7.0的應(yīng)用程序：

TEXT二進(jìn)制文件中所有部分的總數(shù)最多為80 MB 祸穷。

對于MinimumOSVersion7.x到8.x的應(yīng)用程序：

TEXT對于二進(jìn)制文件中每個體系結(jié)構(gòu)片段的每個片段，最大為60 MB 勺三。

對于MinimumOSVersion9.0或更高版本的應(yīng)用程序：__TEXT二進(jìn)制文件中所有部分的總數(shù)最多為500 MB 雷滚。參閱：iTunes Connect開發(fā)者指南

126、修改UISegmentedControl的字體大小

[segment setTitleTextAttributes:@{NSFontAttributeName : [UIFont systemFontOfSize:15.0f]} forState:UIControlStateNormal];

127吗坚、在非ViewController的地方彈出UIAlertController對話框

//? 最好抽成一個分類

UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Title" message:@"message" preferredStyle:UIAlertControllerStyleAlert];

//...

id rootViewController = [UIApplication sharedApplication].delegate.window.rootViewController;

if([rootViewController isKindOfClass:[UINavigationController class]])

{

??? rootViewController = ((UINavigationController *)rootViewController).viewControllers.firstObject;

}

if([rootViewController isKindOfClass:[UITabBarController class]])

{

??? rootViewController = ((UITabBarController *)rootViewController).selectedViewController;

}

[rootViewController presentViewController:alertController animated:YES completion:nil];

128祈远、獲取一個view所屬的控制器

// view分類方法

- (UIViewController *)belongViewController {

??? for (UIView *next = [self superview]; next; next = next.superview) {

??????? UIResponder* nextResponder = [next nextResponder];

??????? if ([nextResponder isKindOfClass:[UIViewController class]]) {

??????????? return (UIViewController *)nextResponder;

??????? }

??? }

??? return nil;

}

129、UIImage和base64互轉(zhuǎn)

// view分類方法

- (NSString *)encodeToBase64String:(UIImage *)image {

return [UIImagePNGRepresentation(image) base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];

}

- (UIImage *)decodeBase64ToImage:(NSString *)strEncodeData {

? NSData *data = [[NSData alloc]initWithBase64EncodedString:strEncodeData options:NSDataBase64DecodingIgnoreUnknownCharacters];

? return [UIImage imageWithData:data];

}

130商源、UIWebView設(shè)置背景透明

[webView setBackgroundColor:[UIColor clearColor]];

[webView setOpaque:NO];

131车份、判斷NSDate是不是今天

NSDateComponents *otherDay = [[NSCalendar currentCalendar] components:NSCalendarUnitEra | NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay fromDate:aDate];

NSDateComponents *today = [[NSCalendar currentCalendar] components:NSCalendarUnitEra | NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay fromDate:[NSDate date]];

if([today day] == [otherDay day] &&

?? [today month] == [otherDay month] &&

?? [today year] == [otherDay year] &&

?? [today era] == [otherDay era]) {

??? // 是今天

}

132、設(shè)置tableView分割線顏色

[self.tableView setSeparatorColor:[UIColor myColor]];

133牡彻、設(shè)置屏幕方向

NSNumber *orientationTarget = [NSNumber numberWithInt:UIInterfaceOrientationLandscapeLeft];

[[UIDevice currentDevice] setValue:orientationTarget forKey:@"orientation"];

[UIViewController attemptRotationToDeviceOrientation];

134扫沼、比較兩個顏色是否相等

- (BOOL)isEqualToColor:(UIColor *)otherColor {

??? CGColorSpaceRef colorSpaceRGB = CGColorSpaceCreateDeviceRGB();

??? UIColor *(^convertColorToRGBSpace)(UIColor*) = ^(UIColor *color) {

??????? if (CGColorSpaceGetModel(CGColorGetColorSpace(color.CGColor)) == kCGColorSpaceModelMonochrome) {

??????????? const CGFloat *oldComponents = CGColorGetComponents(color.CGColor);

??????????? CGFloat components[4] = {oldComponents[0], oldComponents[0], oldComponents[0], oldComponents[1]};

??????????? CGColorRef colorRef = CGColorCreate( colorSpaceRGB, components );

??????????? UIColor *color = [UIColor colorWithCGColor:colorRef];

??????????? CGColorRelease(colorRef);

??????????? return color;???????????

??????? } else

??????????? return color;

??? };

??? UIColor *selfColor = convertColorToRGBSpace(self);

??? otherColor = convertColorToRGBSpace(otherColor);

??? CGColorSpaceRelease(colorSpaceRGB);

??? return [selfColor isEqual:otherColor];

}

135、tableViewCell分割線頂?shù)筋^

- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath {

??? [cell setSeparatorInset:UIEdgeInsetsZero];

??? [cell setLayoutMargins:UIEdgeInsetsZero];

??? cell.preservesSuperviewLayoutMargins = NO;

}

- (void)viewDidLayoutSubviews {

??? [self.tableView setSeparatorInset:UIEdgeInsetsZero];

??? [self.tableView setLayoutMargins:UIEdgeInsetsZero];

}

136庄吼、不讓控制器的view隨著控制器的xib拉伸或壓縮

self.view.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;

137缎除、cocoaPods報錯 : [!] Unable to add a source with url?https://github.com/CocoaPods/Specs.gitnamed master-1.

You can try adding it manually in ~/.cocoapods/repos or via pod repo add.

解決方法：這是因?yàn)殡娔X里安裝了另外一個Xcode導(dǎo)致cocoapods找不到路徑了

在終端執(zhí)行 sudo xcode-select -switch /Applications/Xcode.app 即可

138、安裝cocoapods的時候出現(xiàn) ERROR: While executing gem ... (Errno::EPERM)

Operation not permitted - /usr/bin/pod

解決辦法：直接在終端執(zhí)行 sudo gem install -n /usr/local/bin cocoapods

139霸褒、在狀態(tài)欄增加網(wǎng)絡(luò)請求的菊花伴找，類似safari加載網(wǎng)頁的時候狀態(tài)欄菊花

[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;

140、檢查一個rect是否包含一個point

// point是否在rect內(nèi)

BOOL isContains = CGRectContainsPoint(rect, point);

141废菱、在指定的寬度下技矮，讓UILabel自動設(shè)置最佳font

label.adjustsFontSizeToFitWidth = YES;

142、將一個image保存在相冊中

UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);

或者

#import

[[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{

??????? PHAssetChangeRequest *changeRequest = [PHAssetChangeRequest creationRequestForAssetFromImage:image];

??????? changeRequest.creationDate????????? = [NSDate date];

??? } completionHandler:^(BOOL success, NSError *error) {

??????? if (success) {

??????????? NSLog(@"successfully saved");

??????? }

??????? else {

??????????? NSLog(@"error saving to photos: %@", error);

??????? }

??? }];

143殊轴、修改cell.imageView的大小

UIImage *icon = [UIImage imageNamed:@""];

CGSize itemSize = CGSizeMake(30, 30);

UIGraphicsBeginImageContextWithOptions(itemSize, NO ,0.0);

CGRect imageRect = CGRectMake(0.0, 0.0, itemSize.width, itemSize.height);

[icon drawInRect:imageRect];

cell.imageView.image = UIGraphicsGetImageFromCurrentImageContext();

UIGraphicsEndImageContext();

144衰倦、為一個view添加虛線邊框

CAShapeLayer *border = [CAShapeLayer layer];

??? border.strokeColor = [UIColor colorWithRed:67/255.0f green:37/255.0f blue:83/255.0f alpha:1].CGColor;

??? border.fillColor = nil;

??? border.lineDashPattern = @[@4, @2];

??? border.path = [UIBezierPath bezierPathWithRect:view.bounds].CGPath;

??? border.frame = view.bounds;

??? [view.layer addSublayer:border];

145、UITextView中打開或禁用復(fù)制旁理，剪切樊零，選擇，全選等功能

// 繼承UITextView重寫這個方法

- (BOOL)canPerformAction:(SEL)action withSender:(id)sender

{

// 返回NO為禁用，YES為開啟

??? // 粘貼

??? if (action == @selector(paste:)) return NO;

??? // 剪切

??? if (action == @selector(cut:)) return NO;

??? // 復(fù)制

??? if (action == @selector(copy:)) return NO;

??? // 選擇

??? if (action == @selector(select:)) return NO;

??? // 選中全部

??? if (action == @selector(selectAll:)) return NO;

??? // 刪除

??? if (action == @selector(delete:)) return NO;

??? // 分享

??? if (action == @selector(share)) return NO;

??? return [super canPerformAction:action withSender:sender];

}