UITableView的Group樣式下頂部空白處理

分組列表頭部空白處理UIView*view = [[UIViewalloc] initWithFrame:CGRectMake(0,0,0,0.1)];self.tableView.tableHeaderView = view;

UITableView的plain樣式下超埋，取消區(qū)頭停滯效果

- (void)scrollViewDidScroll:(UIScrollView*)scrollView{? ? CGFloat sectionHeaderHeight = sectionHead.height;if (scrollView.contentOffset.y<=sectionHeaderHeight&&scrollView;.contentOffset.y>=0){scrollView.contentInset= UIEdgeInsetsMake(-scrollView.contentOffset.y,0,0,0);}? ? else if(scrollView.contentOffset.y>=sectionHeaderHeight){scrollView.contentInset= UIEdgeInsetsMake(-sectionHeaderHeight,0,0,0);}}

那個(gè)旭旭，其實(shí)寄狼，還是用Group樣式吧哈哈枫振。

獲取某個(gè)view所在的控制器

- (UIViewController *)viewController{?

UIViewController *viewController =nil;? ?

UIResponder *next=self.nextResponder;

while(next)?

{

if([nextisKindOfClass:[UIViewControllerclass]])

{? ? ?

viewController = (UIViewController *)next;break;? ? ? ? }

next=next.nextResponder;? ?

}

return viewController;

}

兩種方法刪除NSUserDefaults所有記錄

//方法一NSString*appDomain = [[NSBundlemainBundle] bundleIdentifier];[[NSUserDefaultsstandardUserDefaults] removePersistentDomainForName:appDomain];

//方法二- (void)resetDefaults{NSUserDefaults* defs = [NSUserDefaultsstandardUserDefaults];

NSDictionary* dict = [defs dictionaryRepresentation];

for(id key in dict) ?

{ ? ?

? [defs removeObjectForKey:key]; ??

}?

? [defs synchronize];}

打印系統(tǒng)所有已注冊(cè)的字體名稱

#pragma mark - 打印系統(tǒng)所有已注冊(cè)的字體名稱

void enumerateFonts() {

for(NSString*family Namein[UIFont familyNames])? {

NSLog(@"%@",familyName);

NSArray*fontNames = [UIFont fontNamesForFamilyName:familyName];

for(NSString*fontNameinfontNames)? ?

? {

NSLog(@"\t|- %@",fontName);? ? ?

}?

}

}

取圖片某一像素點(diǎn)的顏色 在UIImage的分類中

- (UIColor*)colorAtPixel:(CGPoint)point{

if(!CGRectContainsPoint(CGRectMake(0.0f,0.0f,self.size.width,self.size.height), point))? ?

{

return nil;? ?

}

CGColor SpaceRefcolorSpace =CGColorSpaceCreateDeviceRGB();

int bytesPerPixel =4;

int bytesPerRow = bytesPerPixel *1;

NSUInteger bitsPerComponent =8;

unsignedchar pixelData[4] = {0,0,0,0};

CGContextRef context =CGBitmapContextCreate(pixelData,1,1,? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? bitsPerComponent,bytesPerRow,colorSpace,kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);

CGColorSpaceRelease(colorSpace);

CGContextSetBlendMode(context, kCGBlendModeCopy);

CGContextTranslateCTM(context, -point.x, point.y -self.size.height);

CGContextDrawImage(context,CGRectMake(0.0f,0.0f,self.size.width,self.size.height),self.CGImage);

CGContextRelease(context);

CGFloat red? = (CGFloat)pixelData[0] /255.0f;

CGFloat green = (CGFloat)pixelData[1] /255.0f;

CGFloat blue? = (CGFloat)pixelData[2] /255.0f;

CGFloat alpha = (CGFloat)pixelData[3] /255.0f;

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

}

字符串反轉(zhuǎn)

第一種：- (NSString*)reverseWordsInString:(NSString*)str{

NSMutableString*newString = [[NSMutableStringalloc] initWithCapacity:str.length];

for(NSIntegeri = str.length -1; i >=0; i --)? ?

{unicharch = [str characterAtIndex:i];? ? ?

? ?[newString appendFormat:@"%c", ch];? ? ? ?

}

return newString;

}

//第二種：- (NSString*)reverseWordsInString:(NSString*)str{

NSMutableString*reverString = [NSMutableStringstringWithCapacity:str.length];?

?[str enumerateSubstringsInRange:NSMakeRange(0, str.length) options:NSStringEnumerationReverse|NSStringEnumerationByComposedCharacterSequencesusingBlock:^(NSString*substring,NSRangesubstringRange,NSRangeenclosingRange,BOOL*stop) {? ? ? ? ?

[reverString appendString:substring];? ? ? ? ? ? ? ? ? ? ? ? ? ? ?

}];

return reverString;

}

禁止鎖屏斑鼻，

默認(rèn)情況下蒋纬，當(dāng)設(shè)備一段時(shí)間沒(méi)有觸控動(dòng)作時(shí)，iOS會(huì)鎖住屏幕坚弱。但有一些應(yīng)用是不需要鎖屏的蜀备，比如視頻播放器。

[UIApplicationsharedApplication].idleTimerDisabled= YES;或[[UIApplicationsharedApplication]setIdleTimerDisabled:YES];

模態(tài)推出透明界面

UIViewController*vc = [[UIViewControlleralloc] init];

UINavigationController*na = [[UINavigationControlleralloc] initWithRootViewController:vc];

if([[[UIDevicecurrentDevice] systemVersion] floatValue] >=8.0){? ? na.modalPresentationStyle=UIModalPresentationOverCurrentContext;

}else{

self.modalPresentationStyle=UIModalPresentationCurrentContext;

}

[self presentViewController:na animated:YEScompletion:nil];

Xcode調(diào)試不顯示內(nèi)存占用

editSCheme? 里面有個(gè)選項(xiàng)叫叫做enablezoombie Objects? 取消選中

顯示隱藏文件

//顯示defaults write com.apple.finderAppleShowAllFiles -bool truekillall Finder

//隱藏defaults write com.apple.finderAppleShowAllFiles -bool falsekillall Finder

字符串按多個(gè)符號(hào)分割

image.png

iOS跳轉(zhuǎn)到App Store下載應(yīng)用評(píng)分

[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"itms-apps://itunes.apple.com/WebObjects/MZStore.woa/wa/viewContentsUserReviews?type=Purple+Software&id=APPID"]];

iOS 獲取漢字的拼音

+ (NSString*)transform:(NSString*)chinese{//將NSString裝換成NSMutableString

NSMutableString*pinyin = [chinese mutableCopy];//將漢字轉(zhuǎn)換為拼音(帶音標(biāo))

CFStringTransform((__bridgeCFMutableStringRef)pinyin,NULL, kCFStringTransformMandarinLatin,NO);

NSLog(@"%@", pinyin);//去掉拼音的音標(biāo)

CFStringTransform((__bridgeCFMutableStringRef)pinyin,NULL,kCFStringTransformStripCombiningMarks,NO);

NSLog(@"%@", pinyin);//返回最近結(jié)果returnpinyin;

}

手動(dòng)更改iOS狀態(tài)欄的顏色

- (void)setStatusBarBackgroundColor:(UIColor *)color{? ?

UIView *statusBar = [[[UIApplication sharedApplication]valueForKey:@"statusBarWindow"]valueForKey:@"statusBar"];

if([statusBar respondsToSelector:@selector(setBackgroundColor:)])? ? {? ? ?

? statusBar.backgroundColor = color; ? ? ?

}

}

判斷當(dāng)前ViewController是push還是present的方式顯示的

NSArray*viewcontrollers=self.navigationController.viewControllers;if(viewcontrollers.count >1){if([viewcontrollers objectAtIndex:viewcontrollers.count -1] ==self)? ? {//push方式[self.navigationController popViewControllerAnimated:YES];? ? }}else{//present方式[selfdismissViewControllerAnimated:YEScompletion:nil];}

獲取實(shí)際使用的LaunchImage圖片

- (NSString*)getLaunchImageName{CGSizeviewSize =self.window.bounds.size;// 豎屏NSString*viewOrientation =@"Portrait";NSString*launchImageName =nil;NSArray* imagesDict = [[[NSBundlemainBundle] infoDictionary] valueForKey:@"UILaunchImages"];for(NSDictionary* dictinimagesDict)? ? {CGSizeimageSize =CGSizeFromString(dict[@"UILaunchImageSize"]);if(CGSizeEqualToSize(imageSize, viewSize) && [viewOrientation isEqualToString:dict[@"UILaunchImageOrientation"]])? ? ? ? {? ? ? ? ? ? launchImageName = dict[@"UILaunchImageName"];? ? ? ? ? ? ? ? }? ? ? ? }returnlaunchImageName;}

iOS在當(dāng)前屏幕獲取第一響應(yīng)

UIWindow* keyWindow = [[UIApplicationsharedApplication] keyWindow];UIView* firstResponder = [keyWindow performSelector:@selector(firstResponder)];

判斷對(duì)象是否遵循了某協(xié)議

if([self.selectedControllerconformsToProtocol:@protocol(RefreshPtotocol)]){[self.selectedController performSelector:@selector(onTriggerRefresh)];}

判斷view是不是指定視圖的子視圖

BOOL isView= [textView isDescendantOfView:self.view];

NSArray 快速求總和 最大值 最小值 和 平均值

NSArray *array= [NSArray arrayWithObjects:@"2.0", @"2.3", @"3.0", @"4.0", @"10", nil];CGFloat sum = [[arrayvalueForKeyPath:@"@sum.floatValue"] floatValue];CGFloat avg = [[arrayvalueForKeyPath:@"@avg.floatValue"] floatValue];CGFloatmax=[[arrayvalueForKeyPath:@"@max.floatValue"] floatValue];CGFloatmin=[[arrayvalueForKeyPath:@"@min.floatValue"] floatValue];NSLog(@"%f\n%f\n%f\n%f",sum,avg,max,min);

修改UITextField中Placeholder的文字顏色

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

關(guān)于NSDateFormatter的格式

G:公元時(shí)代荒叶，例如AD公元yy:年的后2位yyyy:完整年MM:月碾阁，顯示為1-12MMM:月，顯示為英文月份簡(jiǎn)寫,如 JanMMMM:月些楣，顯示為英文月份全稱脂凶，如 Janualydd:日，2位數(shù)表示愁茁，如02d:日蚕钦，1-2位顯示，如2EEE:簡(jiǎn)寫星期幾鹅很，如SunEEEE:全寫星期幾嘶居，如Sundayaa:上下午，AM/PMH:時(shí)促煮，24小時(shí)制邮屁，0-23K：時(shí)整袁，12小時(shí)制，0-11m:分樱报，1-2位mm:分葬项，2位s:秒，1-2位ss:秒迹蛤，2位S:毫秒

獲取一個(gè)類的所有子類

+ (NSArray*) allSubclasses{? ? Class myClass = [selfclass];NSMutableArray*mySubclasses = [NSMutableArrayarray];unsignedintnumOfClasses;? ? Class *classes = objc_copyClassList(&numOfClasses;);for(unsignedintci =0; ci < numOfClasses; ci++)? ? {? ? ? ? Class superClass = classes[ci];do{? ? ? ? ? ? superClass = class_getSuperclass(superClass);? ? ? ? }while(superClass && superClass != myClass);if(superClass)? ? ? ? {? ? ? ? ? ? [mySubclasses addObject: classes[ci]];? ? ? ? }? ? }? ? free(classes);returnmySubclasses;}

監(jiān)測(cè)IOS設(shè)備是否設(shè)置了代理民珍，需要CFNetwork.framework

NSDictionary*proxySettings = (__bridgeNSDictionary*)(CFNetworkCopySystemProxySettings());NSArray*proxies = (__bridgeNSArray*)(CFNetworkCopyProxiesForURL((__bridgeCFURLRef_Nonnull)([NSURLURLWithString:@"http://www.baidu.com"]), (__bridgeCFDictionaryRef_Nonnull)(proxySettings)));NSLog(@"\n%@",proxies);NSDictionary*settings = proxies[0];NSLog(@"%@",[settings objectForKey:(NSString*)kCFProxyHostNameKey]);NSLog(@"%@",[settings objectForKey:(NSString*)kCFProxyPortNumberKey]);NSLog(@"%@",[settings objectForKey:(NSString*)kCFProxyTypeKey]);if([[settings objectForKey:(NSString*)kCFProxyTypeKey] isEqualToString:@"kCFProxyTypeNone"]){NSLog(@"沒(méi)代理");}else{NSLog(@"設(shè)置了代理");}

阿拉伯?dāng)?shù)字轉(zhuǎn)中文格式

+(NSString *)translation:(NSString *)arebic{? ? ? NSString *str = arebic;NSArray *arabic_numerals = @[@"1",@"2",@"3",@"4",@"5",@"6",@"7",@"8",@"9",@"0"];NSArray *chinese_numerals = @[@"一",@"二",@"三",@"四",@"五",@"六",@"七",@"八",@"九",@"零"];NSArray *digits= @[@"個(gè)",@"十",@"百",@"千",@"萬(wàn)",@"十",@"百",@"千",@"億",@"十",@"百",@"千",@"兆"];NSDictionary *dictionary= [NSDictionarydictionaryWithObjects:chinese_numeralsforKeys:arabic_numerals];NSMutableArray *sums = [NSMutableArray array];for (int i =0; i < str.length; i ++) {NSString *substr= [strsubstringWithRange:NSMakeRange(i,1)];NSString *a = [dictionaryobjectForKey:substr];NSString *b=digits[str.length-i-1];NSString *sum = [a stringByAppendingString:b];if ([a isEqualToString:chinese_numerals[9]])? ? ? ? {? ? ? ? ? ? if([bisEqualToString:digits[4]]||[bisEqualToString:digits[8]]){? ? ? ? ? ? ? ? sum =b;if ([[sums lastObject] isEqualToString:chinese_numerals[9]])? ? ? ? ? ? ? ? {? ? ? ? ? ? ? ? ? ? [sums removeLastObject];}? ? ? ? ? ? }else? ? ? ? ? ? {? ? ? ? ? ? ? ? sum = chinese_numerals[9];}? ? ? ? ? ? if ([[sums lastObject] isEqualToString:sum])? ? ? ? ? ? {? ? ? ? ? ? ? ? continue;}? ? ? ? }? ? ? ? [sumsaddObject:sum];}? ? NSString *sumStr = [sums componentsJoinedByString:@""];NSString *chinese = [sumStrsubstringToIndex:sumStr.length-1];NSLog(@"%@",str);NSLog(@"%@",chinese);return chinese;}

Base64編碼與NSString對(duì)象或NSData對(duì)象的轉(zhuǎn)換

// Create NSData objectNSData*nsdata = [@"iOS Developer Tips encoded in Base64"dataUsingEncoding:NSUTF8StringEncoding];// Get NSString from NSData object in Base64NSString*base64Encoded = [nsdata base64EncodedStringWithOptions:0];// Print the Base64 encoded stringNSLog(@"Encoded: %@", base64Encoded);// Let's go the other way...// NSData from the Base64 encoded strNSData*nsdataFromBase64String = [[NSDataalloc]? initWithBase64EncodedString:base64Encoded options:0];// Decoded NSString from the NSDataNSString*base64Decoded = [[NSStringalloc]? initWithData:nsdataFromBase64String encoding:NSUTF8StringEncoding];NSLog(@"Decoded: %@", base64Decoded);

取消UICollectionView的隱式動(dòng)畫

UICollectionView在reloadItems的時(shí)候，默認(rèn)會(huì)附加一個(gè)隱式的fade動(dòng)畫盗飒，有時(shí)候很討厭嚷量，尤其是當(dāng)你的cell是復(fù)合cell的情況下(比如cell使用到了UIStackView)。

下面幾種方法都可以幫你去除這些動(dòng)畫

//方法一[UIViewperformWithoutAnimation:^{? ? [collectionViewreloadItemsAtIndexPaths:@[[NSIndexPathindexPathForItem:indexinSection:0]]];}];//方法二[UIViewanimateWithDuration:0animations:^{? ? [collectionViewperformBatchUpdates:^{? ? ? ? [collectionViewreloadItemsAtIndexPaths:@[[NSIndexPathindexPathForItem:indexinSection:0]]];? ? }completion:nil];}];//方法三[UIViewsetAnimationsEnabled:NO];[self.trackPanelperformBatchUpdates:^{? ? [collectionViewreloadItemsAtIndexPaths:@[[NSIndexPathindexPathForItem:indexinSection:0]]];}completion:^(BOOL finished) {? ? [UIViewsetAnimationsEnabled:YES];}];

讓Xcode的控制臺(tái)支持LLDB類型的打印

打開(kāi)終端輸入三條命令:touch ~/.lldbinitechodisplay@import UIKit >> ~/.lldbinitechotargetstop-hookadd-o\"target stop-hook disable\">> ~/.lldbinit

CocoaPods pod install/pod update更新慢的問(wèn)題

pod install --verbose--no-repo-updatepodupdate--verbose--no-repo-update如果不加后面的參數(shù)逆趣，默認(rèn)會(huì)升級(jí)CocoaPods的spec倉(cāng)庫(kù)蝶溶，加一個(gè)參數(shù)可以省略這一步，然后速度就會(huì)提升不少

UIImage 占用內(nèi)存大小

UIImage*image = [UIImageimageNamed:@"aa"];NSUIntegersize? =CGImageGetHeight(image.CGImage) *CGImageGetBytesPerRow(image.CGImage);

GCD timer定時(shí)器

dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT,0);dispatch_source_ttimer= dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER,0,0,queue);dispatch_source_set_timer(timer,dispatch_walltime(NULL,0),1.0*NSEC_PER_SEC,0);//每秒執(zhí)行dispatch_source_set_event_handler(timer, ^{//@"倒計(jì)時(shí)結(jié)束宣渗，關(guān)閉"dispatch_source_cancel(timer);? ? dispatch_async(dispatch_get_main_queue(), ^{? ? });});dispatch_resume(timer);

圖片上繪制文字 寫一個(gè)UIImage的category

- (UIImage*)imageWithTitle:(NSString*)title fontSize:(CGFloat)fontSize{//畫布大小CGSizesize=CGSizeMake(self.size.width,self.size.height);//創(chuàng)建一個(gè)基于位圖的上下文UIGraphicsBeginImageContextWithOptions(size,NO,0.0);//opaque:NO? scale:0.0[selfdrawAtPoint:CGPointMake(0.0,0.0)];//文字居中顯示在畫布上NSMutableParagraphStyle* paragraphStyle = [[NSParagraphStyledefaultParagraphStyle] mutableCopy];? ? paragraphStyle.lineBreakMode =NSLineBreakByCharWrapping;? ? paragraphStyle.alignment=NSTextAlignmentCenter;//文字居中//計(jì)算文字所占的size,文字居中顯示在畫布上CGSizesizeText=[title boundingRectWithSize:self.size options:NSStringDrawingUsesLineFragmentOriginattributes:@{NSFontAttributeName:[UIFontsystemFontOfSize:fontSize]}context:nil].size;CGFloatwidth =self.size.width;CGFloatheight =self.size.height;CGRectrect =CGRectMake((width-sizeText.width)/2, (height-sizeText.height)/2, sizeText.width, sizeText.height);//繪制文字[title drawInRect:rect withAttributes:@{NSFontAttributeName:[UIFontsystemFontOfSize:fontSize],NSForegroundColorAttributeName:[UIColorwhiteColor],NSParagraphStyleAttributeName:paragraphStyle}];//返回繪制的新圖形UIImage*newImage=UIGraphicsGetImageFromCurrentImageContext();UIGraphicsEndImageContext();returnnewImage;}

查找一個(gè)視圖的所有子視圖

- (NSMutableArray *)allSubViewsForView:(UIView *)view{? ? NSMutableArray *array= [NSMutableArray arrayWithCapacity:0];for(UIView *subViewinview.subviews)? ? {? ? ? ? [arrayaddObject:subView];if(subView.subviews.count >0)? ? ? ? {? ? ? ? ? ? [arrayaddObjectsFromArray:[self allSubViewsForView:subView]];? ? ? ? }? ? }returnarray;}

計(jì)算文件大小

//文件大小- (longlong)fileSizeAtPath:(NSString *)path{? ? NSFileManager *fileManager = [NSFileManager defaultManager];if([fileManagerfileExistsAtPath:path])? ? {longlongsize = [fileManagerattributesOfItemAtPath:patherror:nil].fileSize;returnsize;? ? }return0;}//文件夾大小- (longlong)folderSizeAtPath:(NSString *)path{? ? NSFileManager *fileManager = [NSFileManager defaultManager];longlongfolderSize =0;if([fileManagerfileExistsAtPath:path])? ? {? ? ? ? NSArray *childerFiles = [fileManagersubpathsAtPath:path];for(NSString *fileNameinchilderFiles)? ? ? ? {? ? ? ? ? ? NSString *fileAbsolutePath = [pathstringByAppendingPathComponent:fileName];if([fileManagerfileExistsAtPath:fileAbsolutePath])? ? ? ? ? ? {longlongsize = [fileManagerattributesOfItemAtPath:fileAbsolutePatherror:nil].fileSize;? ? ? ? ? ? ? ? folderSize += size;? ? ? ? ? ? }? ? ? ? }? ? }returnfolderSize;}

UIView設(shè)置部分圓角

你是不是也遇到過(guò)這樣的問(wèn)題抖所，一個(gè)button或者label，只要右邊的兩個(gè)角圓角痕囱，或者只要一個(gè)圓角田轧。該怎么辦呢。這就需要圖層蒙版來(lái)幫助我們了

CGRectrect = view.bounds;CGSizeradio =CGSizeMake(30,30);//圓角尺寸UIRectCornercorner =UIRectCornerTopLeft|UIRectCornerTopRight;//這只圓角位置UIBezierPath*path = [UIBezierPathbezierPathWithRoundedRect:rect byRoundingCorners:corner cornerRadii:radio];CAShapeLayer*masklayer = [[CAShapeLayeralloc]init];//創(chuàng)建shapelayermasklayer.frame = view.bounds;masklayer.path = path.CGPath;//設(shè)置路徑view.layer.mask = masklayer;

取上整與取下整

floor(x),有時(shí)候也寫做Floor(x)鞍恢，其功能是“下取整”傻粘，即取不大于x的最大整數(shù) 例如：x=3.14，floor(x)=3y=9.99999帮掉，floor(y)=9與floor函數(shù)對(duì)應(yīng)的是ceil函數(shù)弦悉，即上取整函數(shù)。ceil函數(shù)的作用是求不小于給定實(shí)數(shù)的最小整數(shù)蟆炊。ceil(2)=ceil(1.2)=cei(1.5)=2.00floor函數(shù)與ceil函數(shù)的返回值均為double型

計(jì)算字符串字符長(zhǎng)度稽莉，一個(gè)漢字算兩個(gè)字符

//方法一：- (int)convertToInt:(NSString*)strtemp{intstrlength =0;char* p = (char*)[strtemp cStringUsingEncoding:NSUnicodeStringEncoding];for(inti=0; i<[strtemp lengthOfBytesUsingEncoding:NSUnicodeStringEncoding] ;i++)? ? {if(*p)? ? ? ? {? ? ? ? ? ? p++;? ? ? ? ? ? strlength++;? ? ? ? }else{? ? ? ? ? ? p++;? ? ? ? }? ? }returnstrlength;}//方法二：-(NSUInteger) unicodeLengthOfString: (NSString*) text{NSUIntegerasciiLength =0;for(NSUIntegeri =0; i < text.length; i++)? ? {unicharuc = [text characterAtIndex: i];? ? ? ? asciiLength += isascii(uc) ?1:2;? ? }returnasciiLength;}

給UIView設(shè)置圖片

UIImage*image = [UIImageimageNamed:@"image"];self.MYView.layer.contents = (__bridgeid_Nullable)(image.CGImage);self.MYView.layer.contentsRect =CGRectMake(0,0,0.5,0.5);

防止scrollView手勢(shì)覆蓋側(cè)滑手勢(shì)

[scrollView.panGestureRecognizerrequireGestureRecognizerToFail:self.navigationController.interactivePopGestureRecognizer];

去掉導(dǎo)航欄返回的back標(biāo)題

[[UIBarButtonItemappearance]setBackButtonTitlePositionAdjustment:UIOffsetMake(0,-60)forBarMetrics:UIBarMetricsDefault];

字符串中是否含有中文

+ (BOOL)checkIsChinese:(NSString*)string{for(inti=0; i

dispatch_group的使用

dispatch_group_t dispatchGroup = dispatch_group_create();dispatch_group_enter(dispatchGroup);dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1* NSEC_PER_SEC)), dispatch_get_main_queue(), ^{? ? ? ? NSLog(@"第一個(gè)請(qǐng)求完成");? ? ? ? dispatch_group_leave(dispatchGroup);? ? });? ? dispatch_group_enter(dispatchGroup);? ? dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(10 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{? ? ? ? NSLog(@"第二個(gè)請(qǐng)求完成");dispatch_group_leave(dispatchGroup);});dispatch_group_notify(dispatchGroup, dispatch_get_main_queue(), ^(){? ? ? ? NSLog(@"請(qǐng)求完成");});

UITextField每四位加一個(gè)空格,實(shí)現(xiàn)代理

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string{// 四位加一個(gè)空格if([stringisEqualToString:@""])? ? {// 刪除字符if((textField.text.length -2) %5==0)? ? ? ? {? ? ? ? ? ? textField.text= [textField.textsubstringToIndex:textField.text.length -1];? ? ? ? }returnYES;? ? }else{if(textField.text.length %5==0)? ? ? ? {? ? ? ? ? ? textField.text= [NSString stringWithFormat:@"%@ ", textField.text];? ? ? ? }? ? }returnYES;}

獲取私有屬性和成員變量 #import

//獲取私有屬性 比如設(shè)置UIDatePicker的字體顏色- (void)setTextColor{//獲取所有的屬性，去查看有沒(méi)有對(duì)應(yīng)的屬性u(píng)nsignedintcount =0;? ? objc_property_t *propertys = class_copyPropertyList([UIDatePickerclass], &count);for(inti =0;i < count;i ++)? ? {//獲得每一個(gè)屬性objc_property_t property = propertys[i];//獲得屬性對(duì)應(yīng)的nsstringNSString*propertyName = [NSStringstringWithCString:property_getName(property) encoding:NSUTF8StringEncoding];//輸出打印看對(duì)應(yīng)的屬性NSLog(@"propertyname = %@",propertyName);if([propertyName isEqualToString:@"textColor"])? ? ? ? {? ? ? ? ? ? [datePicker setValue:[UIColorwhiteColor] forKey:propertyName];? ? ? ? }? ? }}

//獲得成員變量 比如修改UIAlertAction的按鈕字體顏色unsignedintcount =0;? ? Ivar *ivars = class_copyIvarList([UIAlertActionclass], &count);for(inti =0;i < count;i ++)? ? {? ? ? ? Ivar ivar = ivars[i];NSString*ivarName = [NSStringstringWithCString:ivar_getName(ivar) encoding:NSUTF8StringEncoding];NSLog(@"uialertion.ivarName = %@",ivarName);if([ivarName isEqualToString:@"_titleTextColor"])? ? ? ? {? ? ? ? ? ? [alertOk setValue:[UIColorblueColor] forKey:@"titleTextColor"];? ? ? ? ? ? [alertCancel setValue:[UIColorpurpleColor] forKey:@"titleTextColor"];? ? ? ? }? ? }

獲取手機(jī)安裝的應(yīng)用

Class c =NSClassFromString(@"LSApplicationWorkspace");ids = [(id)c performSelector:NSSelectorFromString(@"defaultWorkspace")];NSArray*array = [s performSelector:NSSelectorFromString(@"allInstalledApplications")];for(iditeminarray){NSLog(@"%@",[item performSelector:NSSelectorFromString(@"applicationIdentifier")]);//NSLog(@"%@",[item performSelector:NSSelectorFromString(@"bundleIdentifier")]);NSLog(@"%@",[item performSelector:NSSelectorFromString(@"bundleVersion")]);NSLog(@"%@",[item performSelector:NSSelectorFromString(@"shortVersionString")]);}

判斷兩個(gè)日期是否在同一周 寫在NSDate的category里面

- (BOOL)isSameDateWithDate:(NSDate*)date{//日期間隔大于七天之間返回NOif(fabs([selftimeIntervalSinceDate:date]) >=7*24*3600)? ? {returnNO;? ? }NSCalendar*calender = [NSCalendarcurrentCalendar];? ? calender.firstWeekday =2;//設(shè)置每周第一天從周一開(kāi)始//計(jì)算兩個(gè)日期分別為這年第幾周NSUIntegercountSelf = [calender ordinalityOfUnit:NSCalendarUnitWeekdayinUnit:NSCalendarUnitYearforDate:self];NSUIntegercountDate = [calender ordinalityOfUnit:NSCalendarUnitWeekdayinUnit:NSCalendarUnitYearforDate:date];//相等就在同一周盅称，不相等就不在同一周returncountSelf == countDate;}

應(yīng)用內(nèi)打開(kāi)系統(tǒng)設(shè)置界面

//iOS8之后[[UIApplication sharedApplication] openURL:[NSURL URLWithString:UIApplicationOpenSettingsURLString]];//如果App沒(méi)有添加權(quán)限肩祥，顯示的是設(shè)定界面。如果App有添加權(quán)限（例如通知）缩膝，顯示的是App的設(shè)定界面。

//iOS8之前//先添加一個(gè)url type如下圖岸霹，在代碼中調(diào)用如下代碼,即可跳轉(zhuǎn)到設(shè)置頁(yè)面的對(duì)應(yīng)項(xiàng)[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"prefs:root=WIFI"]];可選值如下：About — prefs:root=General&path=AboutAccessibility — prefs:root=General&path=ACCESSIBILITYAirplane Mode On — prefs:root=AIRPLANE_MODEAuto-Lock— prefs:root=General&path=AUTOLOCKBrightness — prefs:root=BrightnessBluetooth — prefs:root=General&path=BluetoothDate&Time— prefs:root=General&path=DATE_AND_TIMEFaceTime — prefs:root=FACETIMEGeneral— prefs:root=GeneralKeyboard — prefs:root=General&path=KeyboardiCloud — prefs:root=CASTLEiCloudStorage&Backup— prefs:root=CASTLE&path=STORAGE_AND_BACKUPInternational — prefs:root=General&path=INTERNATIONALLocation Services — prefs:root=LOCATION_SERVICESMusic — prefs:root=MUSICMusic Equalizer — prefs:root=MUSIC&path=EQMusic VolumeLimit— prefs:root=MUSIC&path=VolumeLimitNetwork — prefs:root=General&path=NetworkNike + iPod — prefs:root=NIKE_PLUS_IPODNotes — prefs:root=NOTESNotification — prefs:root=NOTIFICATI*****_IDPhone — prefs:root=PhonePhotos — prefs:root=PhotosProfile — prefs:root=General&path=ManagedConfigurationListReset— prefs:root=General&path=ResetSafari — prefs:root=SafariSiri — prefs:root=General&path=AssistantSounds — prefs:root=SoundsSoftwareUpdate— prefs:root=General&path=SOFTWARE_UPDATE_LINKStore— prefs:root=STORETwitter — prefs:root=TWITTERUsage— prefs:root=General&path=USAGEVPN — prefs:root=General&path=Network/VPNWallpaper — prefs:root=WallpaperWi-Fi — prefs:root=WIFI

Image.png

屏蔽觸發(fā)事件疾层，2秒后取消屏蔽

[[UIApplicationsharedApplication] beginIgnoringInteractionEvents];dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(2* NSEC_PER_SEC)), dispatch_get_main_queue(), ^{? ? [[UIApplicationsharedApplication] endIgnoringInteractionEvents]});

動(dòng)畫暫停再開(kāi)始

-(void)pauseLayer:(CALayer*)layer{? ? CFTimeIntervalpausedTime= [layer convertTime:CACurrentMediaTime() fromLayer:nil];layer.speed =0.0;layer.timeOffset =pausedTime;}-(void)resumeLayer:(CALayer *)layer{? ? CFTimeIntervalpausedTime= [layer timeOffset];layer.speed =1.0;layer.timeOffset =0.0;layer.beginTime=0.0;CFTimeInterval timeSincePause = [layer convertTime:CACurrentMediaTime() fromLayer:nil] -pausedTime;layer.beginTime= timeSincePause;}

fillRule原理

Image.png

iOS中數(shù)字的格式化

//通過(guò)NSNumberFormatter，同樣可以設(shè)置NSNumber輸出的格式贡避。例如如下代碼：NSNumberFormatter*formatter = [[NSNumberFormatteralloc] init];formatter.numberStyle =NSNumberFormatterDecimalStyle;NSString*string = [formatter stringFromNumber:[NSNumbernumberWithInt:123456789]];NSLog(@"Formatted number string:%@",string);//輸出結(jié)果為：[1223:403] Formatted number string:123,456,789//其中NSNumberFormatter類有個(gè)屬性numberStyle痛黎，它是一個(gè)枚舉型予弧，設(shè)置不同的值可以輸出不同的數(shù)字格式。該枚舉包括：typedefNS_ENUM(NSUInteger,NSNumberFormatterStyle) {NSNumberFormatterNoStyle= kCFNumberFormatterNoStyle,NSNumberFormatterDecimalStyle= kCFNumberFormatterDecimalStyle,NSNumberFormatterCurrencyStyle= kCFNumberFormatterCurrencyStyle,NSNumberFormatterPercentStyle= kCFNumberFormatterPercentStyle,NSNumberFormatterScientificStyle= kCFNumberFormatterScientificStyle,NSNumberFormatterSpellOutStyle= kCFNumberFormatterSpellOutStyle};//各個(gè)枚舉對(duì)應(yīng)輸出數(shù)字格式的效果如下：其中第三項(xiàng)和最后一項(xiàng)的輸出會(huì)根據(jù)系統(tǒng)設(shè)置的語(yǔ)言區(qū)域的不同而不同湖饱。[1243:403] Formatted number string:123456789[1243:403] Formatted number string:123,456,789[1243:403] Formatted number string:￥123,456,789.00[1243:403] Formatted number string:-539,222,988%[1243:403] Formatted number string:1.23456789E8[1243:403] Formatted number string:一億二千三百四十五萬(wàn)六千七百八十九

如何獲取WebView所有的圖片地址掖蛤，

在網(wǎng)頁(yè)加載完成時(shí)，通過(guò)js獲取圖片和添加點(diǎn)擊的識(shí)別方式

//UIWebView- (void)webViewDidFinishLoad:(UIWebView*)webView{//這里是js井厌，主要目的實(shí)現(xiàn)對(duì)url的獲取staticNSString*constjsGetImages =@"function getImages(){\

var objs = document.getElementsByTagName(\"img\");\

var imgScr = '';\

for(var i=0;i

imgScr = imgScr + objs[i].src + '+';\

};\

return imgScr;\

};";? ? [webView stringByEvaluatingJavaScriptFromString:jsGetImages];//注入js方法NSString*urlResult = [webView stringByEvaluatingJavaScriptFromString:@"getImages()"];NSArray*urlArray = [NSMutableArrayarrayWithArray:[urlResult componentsSeparatedByString:@"+"]];//urlResurlt 就是獲取到得所有圖片的url的拼接蚓庭；mUrlArray就是所有Url的數(shù)組}

//WKWebView- (void)webView:(WKWebView*)webView didFinishNavigation:(null_unspecifiedWKNavigation*)navigation{staticNSString*constjsGetImages =@"function getImages(){\

var objs = document.getElementsByTagName(\"img\");\

var imgScr = '';\

for(var i=0;i

imgScr = imgScr + objs[i].src + '+';\

};\

return imgScr;\

};";? ? [webView evaluateJavaScript:jsGetImages completionHandler:nil];? ? [webView evaluateJavaScript:@"getImages()"completionHandler:^(id_Nullable result,NSError* _Nullable error) {NSLog(@"%@",result);? ? }];}

獲取到webview的高度

CGFloat height= [[self.webView stringByEvaluatingJavaScriptFromString:@"document.body.offsetHeight"] floatValue];

navigationBar變?yōu)榧兺该?/p>

//第一種方法//導(dǎo)航欄純透明[self.navigationBar setBackgroundImage:[UIImagenew] forBarMetrics:UIBarMetricsDefault];//去掉導(dǎo)航欄底部的黑線self.navigationBar.shadowImage = [UIImagenew];//第二種方法[[self.navigationBar subviews] objectAtIndex:0].alpha =0;

tabBar同理

[self.tabBar setBackgroundImage:[UIImagenew]];self.tabBar.shadowImage = [UIImagenew];

navigationBar根據(jù)滑動(dòng)距離的漸變色實(shí)現(xiàn)

//第一種- (void)scrollViewDidScroll:(UIScrollView*)scrollView{CGFloatoffsetToShow =200.0;//滑動(dòng)多少就完全顯示CGFloatalpha =1- (offsetToShow - scrollView.contentOffset.y) / offsetToShow;? ? [[self.navigationController.navigationBar subviews] objectAtIndex:0].alpha = alpha;}

//第二種- (void)scrollViewDidScroll:(UIScrollView*)scrollView{CGFloatoffsetToShow =200.0;CGFloatalpha =1- (offsetToShow - scrollView.contentOffset.y) / offsetToShow;? ? [self.navigationController.navigationBar setShadowImage:[UIImagenew]];? ? [self.navigationController.navigationBar setBackgroundImage:[selfimageWithColor:[[UIColororangeColor]colorWithAlphaComponent:alpha]] forBarMetrics:UIBarMetricsDefault];}//生成一張純色的圖片- (UIImage*)imageWithColor:(UIColor*)color{CGRectrect =CGRectMake(0.0f,0.0f,1.0f,1.0f);UIGraphicsBeginImageContext(rect.size);CGContextRefcontext =UIGraphicsGetCurrentContext();CGContextSetFillColorWithColor(context, [colorCGColor]);CGContextFillRect(context, rect);UIImage*theImage =UIGraphicsGetImageFromCurrentImageContext();UIGraphicsEndImageContext();returntheImage;}

iOS 開(kāi)發(fā)中一些相關(guān)的路徑

模擬器的位置:/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs 文檔安裝位置:/Applications/Xcode.app/Contents/Developer/Documentation/DocSets插件保存路徑:~/Library/ApplicationSupport/Developer/Shared/Xcode/Plug-ins自定義代碼段的保存路徑:~/Library/Developer/Xcode/UserData/CodeSnippets/如果找不到CodeSnippets文件夾，可以自己新建一個(gè)CodeSnippets文件夾仅仆。描述文件路徑~/Library/MobileDevice/Provisioning Profiles

navigationItem的BarButtonItem如何緊靠屏幕右邊界或者左邊界器赞？

一般情況下，右邊的item會(huì)和屏幕右側(cè)保持一段距離：

image.png

下面是通過(guò)添加一個(gè)負(fù)值寬度的固定間距的item來(lái)解決墓拜，也可以改變寬度實(shí)現(xiàn)不同的間隔：

UIImage*img = [[UIImageimageNamed:@"icon_cog"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];//寬度為負(fù)數(shù)的固定間距的系統(tǒng)itemUIBarButtonItem*rightNegativeSpacer = [[UIBarButtonItemalloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpacetarget:nilaction:nil];[rightNegativeSpacer setWidth:-15];UIBarButtonItem*rightBtnItem1 = [[UIBarButtonItemalloc]initWithImage:img style:UIBarButtonItemStylePlaintarget:selfaction:@selector(rightButtonItemClicked:)];UIBarButtonItem*rightBtnItem2 = [[UIBarButtonItemalloc]initWithImage:img style:UIBarButtonItemStylePlaintarget:selfaction:@selector(rightButtonItemClicked:)];self.navigationItem.rightBarButtonItems = @[rightNegativeSpacer,rightBtnItem1,rightBtnItem2];

image.png

NSString進(jìn)行URL編碼和解碼

NSString *string= @"http://abc.com?aaa=你好&bbb=tttee";//編碼 打痈酃瘛：http://abc.com?aaa=%E4%BD%A0%E5%A5%BD&bbb=ttteestring= [stringstringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet URLQueryAllowedCharacterSet]];//解碼 打印：http://abc.com?aaa=你好&bbb=ttteestring= [stringstringByRemovingPercentEncoding];

UIWebView設(shè)置User-Agent咳榜。

//設(shè)置NSDictionary*dic = @{@"UserAgent":@"your UserAgent"};[[NSUserDefaultsstandardUserDefaults] registerDefaults:dic];//獲取NSString*agent = [self.WebView stringByEvaluatingJavaScriptFromString:@"navigator.userAgent"];

獲取硬盤總?cè)萘颗c可用容量:

NSFileManager*fileManager = [NSFileManagerdefaultManager];NSDictionary*attributes = [fileManager attributesOfFileSystemForPath:NSHomeDirectory() error:nil];NSLog(@"容量%.2fG",[attributes[NSFileSystemSize] doubleValue] / (powf(1024,3)));NSLog(@"可用%.2fG",[attributes[NSFileSystemFreeSize] doubleValue] / powf(1024,3));

獲取UIColor的RGBA值

UIColor*color = [UIColorcolorWithRed:0.2green:0.3blue:0.9alpha:1.0];constCGFloat*components =CGColorGetComponents(color.CGColor);NSLog(@"Red: %.1f", components[0]);NSLog(@"Green: %.1f", components[1]);NSLog(@"Blue: %.1f", components[2]);NSLog(@"Alpha: %.1f", components[3]);

修改textField的placeholder的字體顏色夏醉、大小

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

AFN移除JSON中的NSNull

AFJSONResponseSerializer *response = [AFJSONResponseSerializer serializer];response.removesKeysWithNullValues = YES;

ceil()和floor()

ceil()功 能：返回大于或者等于指定表達(dá)式的最小整數(shù)

floor()功 能：返回小于或者等于指定表達(dá)式的最大整數(shù)

UIWebView里面的圖片自適應(yīng)屏幕

在webView加載完的代理方法里面這樣寫：

- (void)webViewDidFinishLoad:(UIWebView *)webView{? ? NSString *js= @"function imgAutoFit() { \

var imgs = document.getElementsByTagName('img'); \

for (var i = 0; i < imgs.length; ++i) { \

var img = imgs[i]; \

img.style.maxWidth = %f; \

} \

}";js= [NSString stringWithFormat:js,[UIScreen mainScreen].bounds.size.width-20];[webView stringByEvaluatingJavaScriptFromString:js];[webView stringByEvaluatingJavaScriptFromString:@"imgAutoFit()"];}

持續(xù)更新中……。

本文轉(zhuǎn)自：iOS_小松哥