iOS开发笔记

1、设置UILabel行间距

NSMutableAttributedString* attrString = [[NSMutableAttributedString alloc] initWithString:label.text];

NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc] init];

[style setLineSpacing:20];

[attrString addAttribute:NSParagraphStyleAttributeName value:style range:NSMakeRange(0, label.text.length)];

label.attributedText = attrString;

// 或者使用xib，看下gif图

2、当使用-performSelector:withObject:withObject:afterDelay:方法时，需要传入多参数问题

// 方法一、

// 把参数放进一个数组／字典，直接把数组／字典当成一个参数传过去，具体方法实现的地方再解析这个数组／字典

NSArray * array =

[NSArray arrayWithObjects: @"first", @"second", nil];

[self performSelector:@selector(fooFirstInput:) withObject: array afterDelay:15.0];

// 方法二、

// 使用NSInvocation

SEL aSelector = NSSelectorFromString(@"doSoming:argument2:");

NSInteger argument1 = 10;

NSString *argument2 = @"argument2";

if([self respondsToSelector:aSelector]) {

NSInvocation *inv = [NSInvocation invocationWithMethodSignature:[self methodSignatureForSelector:aSelector]];

[inv setSelector:aSelector];

[inv setTarget:self];

[inv setArgument:&(argument1) atIndex:2];

[inv setArgument:&(argument2) atIndex:3];

[inv performSelector:@selector(invoke) withObject:nil afterDelay:15.0];

}

3、UILabel显示不同颜色字体

NSMutableAttributedString * string = [[NSMutableAttributedString alloc] initWithString:label.text];

[string addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(0,5)];

[string addAttribute:NSForegroundColorAttributeName value:[UIColor greenColor] range:NSMakeRange(5,6)];

[string addAttribute:NSForegroundColorAttributeName value:[UIColor blueColor] range:NSMakeRange(11,5)];

label.attributedText = string;

4、比较两个CGRect/CGSize/CGPoint是否相等

if (CGRectEqualToRect(rect1, rect2)) { // 两个区域相等

// do some

}

if (CGPointEqualToPoint(point1, point2)) { // 两个点相等

// do some

}

if (CGSizeEqualToSize(size1, size2)) { // 两个size相等

// do some

}

5、比较两个NSDate相差多少小时

NSDate* date1 = someDate;

NSDate* date2 = someOtherDate;

NSTimeInterval distanceBetweenDates = [date1 timeIntervalSinceDate:date2];

double secondsInAnHour = 3600;

// 除以3600是把秒化成小时，除以60得到结果为相差的分钟数

NSInteger hoursBetweenDates = distanceBetweenDates / secondsInAnHour;

6、每个cell之间增加间距

// 方法一，每个分区只显示一行cell，分区头当作你想要的间距(注意，从数据源数组中取值的时候需要用indexPath.section而不是indexPath.row)

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView

{

return yourArry.count;

}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section

{

return 1;

}

-(CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section

{

return cellSpacingHeight;

}

// 方法二，在cell的contentView上加个稍微低一点的view，cell上原本的内容放在你的view上，而不是contentView上，这样能伪造出一个间距来。

// 方法三，自定义cell，重写setFrame：方法

- (void)setFrame:(CGRect)frame

{

frame.size.height -= 20;

[super setFrame:frame];

}

7、播放一张张连续的图片

// 加入现在有三张图片分别为animate_1、animate_2、animate_3

// 方法一

imageView.animationImages = @[[UIImage imageNamed:@"animate_1"], [UIImage imageNamed:@"animate_2"], [UIImage imageNamed:@"animate_3"]];

imageView.animationDuration = 1.0;

// 方法二

imageView.image = [UIImage animatedImageNamed:@"animate_" duration:1.0];

// 方法二解释下，这个方法会加载animate_为前缀的，后边0-1024，也就是animate_0、animate_1一直到animate_1024

8、加载gif图片

推荐使用这个框架 FLAnimatedImage

9、防止离屏渲染为image添加圆角

// image分类

- (UIImage *)circleImage

{

// NO代表透明

UIGraphicsBeginImageContextWithOptions(self.size, NO, 1);

// 获得上下文

CGContextRef ctx = UIGraphicsGetCurrentContext();

// 添加一个圆

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

// 方形变圆形

CGContextAddEllipseInRect(ctx, rect);

// 裁剪

CGContextClip(ctx);

// 将图片画上去

[self drawInRect:rect];

UIImage *image = UIGraphicsGetImageFromCurrentImageContext();

UIGraphicsEndImageContext();

return image;

}

10、查看系统所有字体

// 打印字体

for (id familyName in [UIFont familyNames]) {

NSLog(@"%@", familyName);

for (id fontName in [UIFont fontNamesForFamilyName:familyName]) NSLog(@" %@", fontName);

}

// 也可以进入这个网址查看 http://iosfonts.com/

11、获取随机数

NSInteger i = arc4random();

12、获取随机数小数(0-1之间)

#define ARC4RANDOM_MAX 0x100000000

double val = ((double)arc4random() / ARC4RANDOM_MAX);

13、AVPlayer视频播放完成的通知监听

[[NSNotificationCenter defaultCenter]

addObserver:self

selector:@selector(videoPlayEnd)

name:AVPlayerItemDidPlayToEndTimeNotification

object:nil];

14、判断两个rect是否有交叉

if (CGRectIntersectsRect(rect1, rect2)) {

}

15、判断一个字符串是否为数字

NSCharacterSet *notDigits = [[NSCharacterSet decimalDigitCharacterSet] invertedSet];

if ([str rangeOfCharacterFromSet:notDigits].location == NSNotFound)

{

// 是数字

} else

{

// 不是数字

}

16、将一个view保存为pdf格式

- (void)createPDFfromUIView:(UIView*)aView saveToDocumentsWithFileName:(NSString*)aFilename

{

NSMutableData *pdfData = [NSMutableData data];

UIGraphicsBeginPDFContextToData(pdfData, aView.bounds, nil);

UIGraphicsBeginPDFPage();

CGContextRef pdfContext = UIGraphicsGetCurrentContext();

[aView.layer renderInContext:pdfContext];

UIGraphicsEndPDFContext();

NSArray* documentDirectories = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES);

NSString* documentDirectory = [documentDirectories objectAtIndex:0];

NSString* documentDirectoryFilename = [documentDirectory stringByAppendingPathComponent:aFilename];

[pdfData writeToFile:documentDirectoryFilename atomically:YES];

NSLog(@"documentDirectoryFileName: %@",documentDirectoryFilename);

}

17、让一个view在父视图中心

child.center = [parent convertPoint:parent.center fromView:parent.superview];

18、获取当前导航控制器下前一个控制器

- (UIViewController *)backViewController

{

NSInteger myIndex = [self.navigationController.viewControllers indexOfObject:self];

if ( myIndex != 0 && myIndex != NSNotFound ) {

return [self.navigationController.viewControllers objectAtIndex:myIndex-1];

} else {

return nil;

}

19、保存UIImage到本地

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);

NSString *filePath = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"Image.png"];

[UIImagePNGRepresentation(image) writeToFile:filePath atomically:YES];

20、键盘上方增加工具栏

UIToolbar *keyboardDoneButtonView = [[UIToolbar alloc] init];

[keyboardDoneButtonView sizeToFit];

UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithTitle:@"Done"

style:UIBarButtonItemStyleBordered target:self

action:@selector(doneClicked:)];

[keyboardDoneButtonView setItems:[NSArray arrayWithObjects:doneButton, nil]];

txtField.inputAccessoryView = keyboardDoneButtonView;

21、copy一个view

因为UIView没有实现copy协议，因此找不到copyWithZone方法，使用copy的时候导致崩溃

但是我们可以通过归档再解档实现copy，这相当于对视图进行了一次深拷贝，代码如下

id copyOfView =

[NSKeyedUnarchiver unarchiveObjectWithData:[NSKeyedArchiver archivedDataWithRootObject:originalView]];

22、在image上绘制文字并生成新的image

UIFont *font = [UIFont boldSystemFontOfSize:12];

UIGraphicsBeginImageContext(image.size);

[image drawInRect:CGRectMake(0,0,image.size.width,image.size.height)];

CGRect rect = CGRectMake(point.x, point.y, image.size.width, image.size.height);

[[UIColor whiteColor] set];

[text drawInRect:CGRectIntegral(rect) withFont:font];

UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();

UIGraphicsEndImageContext();

23、判断一个view是否为另一个view的子视图

// 如果myView是self.view本身，也会返回yes

BOOL isSubView = [myView isDescendantOfView:self.view];

24、判断一个字符串是否包含另一个字符串

// 方法一、这种方法只适用于iOS8之后，如果是配iOS8之前用方法二

if ([str containsString:otherStr]) NSLog(@"包含");

// 方法二

NSRange range = [str rangeOfString:otherStr];

if (range.location != NSNotFound) NSLog(@"包含");

25、UICollectionView自动滚动到某行

// 重写viewDidLayoutSubviews方法

-(void)viewDidLayoutSubviews {

[super viewDidLayoutSubviews];

[self.collectionView scrollToItemAtIndexPath:indexPath atScrollPosition:UICollectionViewScrollPositionCenteredVertically animated:NO];

}

26、修改系统UIAlertController

// 但是据说这种方法会被App Store拒绝(慎用！)

UIAlertController *alertVC = [UIAlertController alertControllerWithTitle:@"" message:@"" preferredStyle:UIAlertControllerStyleActionSheet];

NSMutableAttributedString *hogan = [[NSMutableAttributedString alloc] initWithString:@"我是一个大文本"];

[hogan addAttribute:NSFontAttributeName

value:[UIFont systemFontOfSize:30]

range:NSMakeRange(4, 1)];

[hogan addAttribute:NSForegroundColorAttributeName

value:[UIColor redColor]

range:NSMakeRange(4, 1)];

[alertVC setValue:hogan forKey:@"attributedTitle"];

UIAlertAction *button = [UIAlertAction actionWithTitle:@"Label text" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action){ }];

UIImage *accessoryImage = [UIImage imageNamed:@"1"];

[button setValue:accessoryImage forKey:@"image"];

[alertVC addAction:button];

[self presentViewController:alertVC animated:YES completion:nil];

27、判断某一行的cell是否已经显示

CGRect cellRect = [tableView rectForRowAtIndexPath:indexPath];

BOOL completelyVisible = CGRectContainsRect(tableView.bounds, cellRect);

28、让导航控制器pop回指定的控制器

NSMutableArray *allViewControllers = [NSMutableArray arrayWithArray:[self.navigationController viewControllers]];

for (UIViewController *aViewController in allViewControllers) {

if ([aViewController isKindOfClass:[RequiredViewController class]]) {

[self.navigationController popToViewController:aViewController animated:NO];

}

29、动画修改label上的文字

// 方法一

CATransition *animation = [CATransition animation];

animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];

animation.type = kCATransitionFade;

animation.duration = 0.75;

[self.label.layer addAnimation:animation forKey:@"kCATransitionFade"];

self.label.text = @"New";

// 方法二

[UIView transitionWithView:self.label

duration:0.25f

options:UIViewAnimationOptionTransitionCrossDissolve

animations:^{

self.label.text = @"Well done!";

} completion:nil];

// 方法三

[UIView animateWithDuration:1.0

animations:^{

self.label.alpha = 0.0f;

self.label.text = @"newText";

self.label.alpha = 1.0f;

}];

30、判断字典中是否包含某个key值

if ([dic objectForKey:@"yourKey"]) {

NSLog(@"有这个值");

} else {

NSLog(@"没有这个值");

}

31、获取屏幕方向

UIInterfaceOrientation orientation = [UIApplication sharedApplication].statusBarOrientation;

if(orientation == 0) //Default orientation

//默认

else if(orientation == UIInterfaceOrientationPortrait)

//竖屏

else if(orientation == UIInterfaceOrientationLandscapeLeft)

// 左横屏

else if(orientation == UIInterfaceOrientationLandscapeRight)

//右横屏

32、设置UIImage的透明度

// 方法一、添加UIImage分类

- (UIImage *)imageByApplyingAlpha:(CGFloat) alpha {

UIGraphicsBeginImageContextWithOptions(self.size, NO, 0.0f);

CGContextRef ctx = UIGraphicsGetCurrentContext();

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

CGContextScaleCTM(ctx, 1, -1);

CGContextTranslateCTM(ctx, 0, -area.size.height);

CGContextSetBlendMode(ctx, kCGBlendModeMultiply);

CGContextSetAlpha(ctx, alpha);

CGContextDrawImage(ctx, area, self.CGImage);

UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();

UIGraphicsEndImageContext();

return newImage;

}

// 方法二、如果没有奇葩需求，干脆用UIImageView设置透明度

UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageWithName:@"yourImage"]];

imageView.alpha = 0.5;

33、Attempt to mutate immutable object with insertString:atIndex:

这个错是因为你拿字符串调用insertString:atIndex:方法的时候，调用对象不是NSMutableString，应该先转成这个类型再调用

34、UIWebView添加单击手势不响应

UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(webViewClick)];

tap.delegate = self;

[_webView addGestureRecognizer:tap];

// 因为webView本身有一个单击手势，所以再添加会造成手势冲突，从而不响应。需要绑定手势代理，并实现下边的代理方法

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{

return YES;

}

35、获取手机RAM容量

// 需要导入#import

mach_port_t host_port;

mach_msg_type_number_t host_size;

vm_size_t pagesize;

host_port = mach_host_self();

host_size = sizeof(vm_statistics_data_t) / sizeof(integer_t);

host_page_size(host_port, &pagesize);

vm_statistics_data_t vm_stat;

if (host_statistics(host_port, HOST_VM_INFO, (host_info_t)&vm_stat, &host_size) != KERN_SUCCESS) {

NSLog(@"Failed to fetch vm statistics");

}

/* Stats in bytes */

natural_t mem_used = (vm_stat.active_count +

vm_stat.inactive_count +

vm_stat.wire_count) * pagesize;

natural_t mem_free = vm_stat.free_count * pagesize;

natural_t mem_total = mem_used + mem_free;

NSLog(@"已用: %u 可用: %u 总共: %u", mem_used, mem_free, mem_total);

36、地图上两个点之间的实际距离

// 需要导入#import

CLLocation *locA = [[CLLocation alloc] initWithLatitude:34 longitude:113];

CLLocation *locB = [[CLLocation alloc] initWithLatitude:31.05 longitude:121.76];

// CLLocationDistance求出的单位为米

CLLocationDistance distance = [locA distanceFromLocation:locB];

37、在应用中打开设置的某个界面

// 打开设置->通用

[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"prefs:root=General"]];

// 以下是设置其他界面

prefs:root=General&path=About

prefs:root=General&path=ACCESSIBILITY

prefs:root=AIRPLANE_MODE

prefs:root=General&path=AUTOLOCK

prefs:root=General&path=USAGE/CELLULAR_USAGE

prefs:root=Brightness

prefs:root=Bluetooth

prefs:root=General&path=DATE_AND_TIME

prefs:root=FACETIME

prefs:root=General

prefs:root=General&path=Keyboard

prefs:root=CASTLE

prefs:root=CASTLE&path=STORAGE_AND_BACKUP

prefs:root=General&path=INTERNATIONAL

prefs:root=LOCATION_SERVICES

prefs:root=ACCOUNT_SETTINGS

prefs:root=MUSIC

prefs:root=MUSIC&path=EQ

prefs:root=MUSIC&path=VolumeLimit

prefs:root=General&path=Network

prefs:root=NIKE_PLUS_IPOD

prefs:root=NOTES

prefs:root=NOTIFICATIONS_ID

prefs:root=Phone

prefs:root=Photos

prefs:root=General&path=ManagedConfigurationList

prefs:root=General&path=Reset

prefs:root=Sounds&path=Ringtone

prefs:root=Safari

prefs:root=General&path=Assistant

prefs:root=Sounds

prefs:root=General&path=SOFTWARE_UPDATE_LINK

prefs:root=STORE

prefs:root=TWITTER

prefs:root=FACEBOOK

prefs:root=General&path=USAGE prefs:root=VIDEO

prefs:root=General&path=Network/VPN

prefs:root=Wallpaper

prefs:root=WIFI

prefs:root=INTERNET_TETHERING

prefs:root=Phone&path=Blocked

prefs:root=DO_NOT_DISTURB

38、在UITextView中显示html文本

UITextView *textView = [[UITextView alloc] initWithFrame:CGRectMake(20, 30, 100, 199)];

textView.backgroundColor = [UIColor redColor];

[self.view addSubview:textView];

NSString *htmlString = @"

![](http://blogs.babble.com/famecrawler/files/2010/11/mickey_mouse-1097.jpg)";

NSAttributedString *attributedString = [[NSAttributedString alloc] initWithData: [htmlString dataUsingEncoding:NSUnicodeStringEncoding] options: @{ NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType } documentAttributes: nil error: nil];

textView.attributedText = attributedString;

39、监听scrollView是否滚动到了顶部／底部

-(void)scrollViewDidScroll: (UIScrollView*)scrollView

{

float scrollViewHeight = scrollView.frame.size.height;

float scrollContentSizeHeight = scrollView.contentSize.height;

float scrollOffset = scrollView.contentOffset.y;

if (scrollOffset == 0)

{

// 滚动到了顶部

}

else if (scrollOffset + scrollViewHeight == scrollContentSizeHeight)

{

// 滚动到了底部

}

40、UISlider增量／减量为固定值(假如为5)

- (void)setupSlider

{

UISlider *slider = [[UISlider alloc] init];

[self.view addSubview:slider];

[slider addTarget:self action:@selector(sliderAction:) forControlEvents:UIControlEventValueChanged];

slider.maximumValue = 100;

slider.minimumValue = 0;

slider.frame = CGRectMake(200, 20, 100, 30);

}

- (void)sliderAction:(UISlider *)slider

{

[slider setValue:((int)((slider.value + 2.5) / 5) * 5) animated:NO];

}

41、选中textField或者textView所有文本(我这里以textView为例)

[self.textView setSelectedTextRange:[self.textView textRangeFromPosition:self.textView.beginningOfDocument toPosition:self.textView.endOfDocument]]

42、从导航控制器中删除某个控制器

// 方法一、知道这个控制器所处的导航控制器下标

NSMutableArray *navigationArray = [[NSMutableArray alloc] initWithArray: self.navigationController.viewControllers];

[navigationArray removeObjectAtIndex: 2];

self.navigationController.viewControllers = navigationArray;

// 方法二、知道具体是哪个控制器

NSArray* tempVCA = [self.navigationController viewControllers];

for(UIViewController *tempVC in tempVCA)

{

if([tempVC isKindOfClass:[urViewControllerClass class]])

{

[tempVC removeFromParentViewController];

}

43、隐藏UITextView/UITextField光标

textField.tintColor = [UIColor clearColor];

44、当UITextView/UITextField中没有文字时，禁用回车键

textField.enablesReturnKeyAutomatically = YES;

45、字符串encode编码(编码url字符串不成功的问题)

// 我们一般用这个方法处理stringByAddingPercentEscapesUsingEncoding但是这个方法好想不会处理／和&这种特殊符号，这种情况就需要用下边这个方法处理

@implementation NSString (NSString_Extended)

- (NSString *)urlencode {

NSMutableString *output = [NSMutableString string];

const unsigned char *source = (const unsigned char *)[self UTF8String];

int sourceLen = strlen((const char *)source);

for (int i = 0; i < sourceLen; ++i) {

const unsigned char thisChar = source[i];

if (thisChar == ' '){

[output appendString:@"+"];

} else if (thisChar == '.' || thisChar == '-' || thisChar == '_' || thisChar == '~' ||

(thisChar >= 'a' && thisChar = 'A' && thisChar = '0' && thisChar <= '9')) {

[output appendFormat:@"%c", thisChar];

} else {

[output appendFormat:@"%%X", thisChar];

}

return output;

}

46、计算UILabel上某段文字的frame

@implementation UILabel (TextRect)

- (CGRect)boundingRectForCharacterRange:(NSRange)range

{

NSTextStorage *textStorage = [[NSTextStorage alloc] initWithAttributedString:[self attributedText]];

NSLayoutManager *layoutManager = [[NSLayoutManager alloc] init];

[textStorage addLayoutManager:layoutManager];

NSTextContainer *textContainer = [[NSTextContainer alloc] initWithSize:[self bounds].size];

textContainer.lineFragmentPadding = 0;

[layoutManager addTextContainer:textContainer];

NSRange glyphRange;

[layoutManager characterRangeForGlyphRange:range actualGlyphRange:&glyphRange];

return [layoutManager boundingRectForGlyphRange:glyphRange inTextContainer:textContainer];

}

47、获取随机UUID

NSString *result;

if([[[UIDevice currentDevice] systemVersion] floatValue] > 6.0)

{

result = [[NSUUID UUID] UUIDString];

}

else

{

CFUUIDRef uuidRef = CFUUIDCreate(NULL);

CFStringRef uuid = CFUUIDCreateString(NULL, uuidRef);

CFRelease(uuidRef);

result = (__bridge_transfer NSString *)uuid;

}

48、仿苹果抖动动画

#define RADIANS(degrees) (((degrees) * M_PI) / 180.0)

- (void)startAnimate {

view.transform = CGAffineTransformRotate(CGAffineTransformIdentity, RADIANS(-5));

[UIView animateWithDuration:0.25 delay:0.0 options:(UIViewAnimationOptionAllowUserInteraction | UIViewAnimationOptionRepeat | UIViewAnimationOptionAutoreverse) animations:^ {

view.transform = CGAffineTransformRotate(CGAffineTransformIdentity, RADIANS(5));

} completion:nil];

}

- (void)stopAnimate {

[UIView animateWithDuration:0.25 delay:0.0 options:(UIViewAnimationOptionAllowUserInteraction | UIViewAnimationOptionBeginFromCurrentState | UIViewAnimationOptionCurveLinear) animations:^ {

view.transform = CGAffineTransformIdentity;

} completion:nil];

}

49、修改UISearBar内部背景颜色

UITextField *textField = [_searchBar valueForKey:@"_searchField"];

textField.backgroundColor = [UIColor redColor];

50、UITextView滚动到顶部

// 方法一

[self.textView scrollRangeToVisible:NSMakeRange(0, 0)];

// 方法二

[self.textView setContentOffset:CGPointZero animated:YES];

51、通知监听APP生命周期

UIApplicationDidEnterBackgroundNotification 应用程序进入后台

UIApplicationWillEnterForegroundNotification 应用程序将要进入前台

UIApplicationDidFinishLaunchingNotification 应用程序完成启动

UIApplicationDidFinishLaunchingNotification 应用程序由挂起变的活跃

UIApplicationWillResignActiveNotification 应用程序挂起(有电话进来或者锁屏)

UIApplicationDidReceiveMemoryWarningNotification 应用程序收到内存警告

UIApplicationDidReceiveMemoryWarningNotification 应用程序终止(后台杀死、手机关机等)

UIApplicationSignificantTimeChangeNotification 当有重大时间改变(凌晨0点，设备时间被修改，时区改变等)

UIApplicationWillChangeStatusBarOrientationNotification 设备方向将要改变

UIApplicationDidChangeStatusBarOrientationNotification 设备方向改变

UIApplicationWillChangeStatusBarFrameNotification 设备状态栏frame将要改变

UIApplicationDidChangeStatusBarFrameNotification 设备状态栏frame改变

UIApplicationBackgroundRefreshStatusDidChangeNotification 应用程序在后台下载内容的状态发生变化

UIApplicationProtectedDataWillBecomeUnavailable 本地受保护的文件被锁定,无法访问

UIApplicationProtectedDataWillBecomeUnavailable 本地受保护的文件可用了

52、触摸事件类型

UIControlEventTouchCancel 取消控件当前触发的事件

UIControlEventTouchDown 点按下去的事件

UIControlEventTouchDownRepeat 重复的触动事件

UIControlEventTouchDragEnter 手指被拖动到控件的边界的事件

UIControlEventTouchDragExit 一个手指从控件内拖到外界的事件

UIControlEventTouchDragInside 手指在控件的边界内拖动的事件

UIControlEventTouchDragOutside 手指在控件边界之外被拖动的事件

UIControlEventTouchUpInside 手指处于控制范围内的触摸事件

UIControlEventTouchUpOutside 手指超出控制范围的控制中的触摸事件

53、UITextField文字周围增加边距

// 子类化UITextField，增加insert属性

@interface WZBTextField : UITextField

@property (nonatomic, assign) UIEdgeInsets insets;

@end

// 在.m文件重写下列方法

- (CGRect)textRectForBounds:(CGRect)bounds {

CGRect paddedRect = UIEdgeInsetsInsetRect(bounds, self.insets);

if (self.rightViewMode == UITextFieldViewModeAlways || self.rightViewMode == UITextFieldViewModeUnlessEditing) {

return [self adjustRectWithWidthRightView:paddedRect];

}

return paddedRect;

}

- (CGRect)placeholderRectForBounds:(CGRect)bounds {

CGRect paddedRect = UIEdgeInsetsInsetRect(bounds, self.insets);

if (self.rightViewMode == UITextFieldViewModeAlways || self.rightViewMode == UITextFieldViewModeUnlessEditing) {

return [self adjustRectWithWidthRightView:paddedRect];

}

return paddedRect;

}

- (CGRect)editingRectForBounds:(CGRect)bounds {

CGRect paddedRect = UIEdgeInsetsInsetRect(bounds, self.insets);

if (self.rightViewMode == UITextFieldViewModeAlways || self.rightViewMode == UITextFieldViewModeWhileEditing) {

return [self adjustRectWithWidthRightView:paddedRect];

}

return paddedRect;

}

- (CGRect)adjustRectWithWidthRightView:(CGRect)bounds {

CGRect paddedRect = bounds;

paddedRect.size.width -= CGRectGetWidth(self.rightView.frame);

return paddedRect;

}

54、监听UISlider拖动状态

// 添加事件

[slider addTarget:self action:@selector(sliderValurChanged:forEvent:) forControlEvents:UIControlEventValueChanged];

// 实现方法

- (void)sliderValurChanged:(UISlider*)slider forEvent:(UIEvent*)event {

UITouch *touchEvent = [[event allTouches] anyObject];

switch (touchEvent.phase) {

case UITouchPhaseBegan:

NSLog(@"开始拖动");

break;

case UITouchPhaseMoved:

NSLog(@"正在拖动");

break;

case UITouchPhaseEnded:

NSLog(@"结束拖动");

break;

default:

break;

}

55、设置UITextField光标位置

// textField需要设置的textField，index要设置的光标位置

- (void)cursorLocation:(UITextField *)textField index:(NSInteger)index

{

NSRange range = NSMakeRange(index, 0);

UITextPosition *start = [textField positionFromPosition:[textField beginningOfDocument] offset:range.location];

UITextPosition *end = [textField positionFromPosition:start offset:range.length];

[textField setSelectedTextRange:[textField textRangeFromPosition:start toPosition:end]];

}

56、去除webView底部黑色

[webView setBackgroundColor:[UIColor clearColor]];

[webView setOpaque:NO];

for (UIView *v1 in [webView subviews])

{

if ([v1 isKindOfClass:[UIScrollView class]])

{

for (UIView *v2 in v1.subviews)

{

if ([v2 isKindOfClass:[UIImageView class]])

{

v2.hidden = YES;

}

57、获取collectionViewCell在屏幕中的frame

UICollectionViewLayoutAttributes *attributes = [collectionView layoutAttributesForItemAtIndexPath:indexPath];

CGRect cellRect = attributes.frame;

CGRect cellFrameInSuperview = [collectionView convertRect:cellRect toView:[cv superview]];

58、比较两个UIImage是否相等

- (BOOL)image:(UIImage *)image1 isEqualTo:(UIImage *)image2

{

NSData *data1 = UIImagePNGRepresentation(image1);

NSData *data2 = UIImagePNGRepresentation(image2);

return [data1 isEqual:data2];

}

59、解决当UIScrollView上有UIButton的时候，触摸到button滑动不了的问题

// 子类化UIScrollView，并重写以下方法

- (instancetype)initWithFrame:(CGRect)frame {

if (self = [super initWithFrame:frame]) {

self.delaysContentTouches = NO;

}

return self;

}

- (BOOL)touchesShouldCancelInContentView:(UIView *)view {

if ([view isKindOfClass:UIButton.class]) {

return YES;

}

return [super touchesShouldCancelInContentView:view];

}

60、UITextView中的文字添加阴影效果

- (void)setTextLayer:(UITextView *)textView color:(UIColor *)color

{

CALayer *textLayer = ((CALayer *)[textView.layer.sublayers objectAtIndex:0]);

textLayer.shadowColor = color.CGColor;

textLayer.shadowOffset = CGSizeMake(0.0f, 1.0f);

textLayer.shadowOpacity = 1.0f;

textLayer.shadowRadius = 1.0f;

}

61、MD5加密

+ (NSString *)md5:(NSString *)str

{

const char *concat_str = [str UTF8String];

unsigned char result[CC_MD5_DIGEST_LENGTH];

CC_MD5(concat_str, (unsigned int)strlen(concat_str), result);

NSMutableString *hash = [NSMutableString string];

for (int i =0; i<16; i++){

[hash appendFormat:@"X", result[i]];

}

return [hash uppercaseString];

}

62、base64加密

@interface NSData (Base64)

/**

* @brief 字符串base64后转data

+ (NSData *)dataWithBase64EncodedString:(NSString *)string

{

if (![string length]) return nil;

NSData *decoded = nil;

#if __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_9 || __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_7_0

if (![NSData instancesRespondToSelector:@selector(initWithBase64EncodedString:options:)])

{

#pragma clang diagnostic push

#pragma clang diagnostic ignored "-Wdeprecated-declarations"

decoded = [[self alloc] initWithBase64Encoding:[string stringByReplacingOccurrencesOfString:@"[^A-Za-z0-9+/=]" withString:@"" options:NSRegularExpressionSearch range:NSMakeRange(0, [string length])]];

#pragma clang diagnostic pop

}

else

#endif

{

decoded = [[self alloc] initWithBase64EncodedString:string options:NSDataBase64DecodingIgnoreUnknownCharacters];

}

return [decoded length]? decoded: nil;

}

/**

* @brief NSData转string

* @param wrapWidth 换行长度 76 64

- (NSString *)base64EncodedStringWithWrapWidth:(NSUInteger)wrapWidth

{

if (![self length]) return nil;

NSString *encoded = nil;

#if __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_9 || __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_7_0

if (![NSData instancesRespondToSelector:@selector(base64EncodedStringWithOptions:)])

{

#pragma clang diagnostic push

#pragma clang diagnostic ignored "-Wdeprecated-declarations"

encoded = [self base64Encoding];

#pragma clang diagnostic pop

}

else

#endif

{

switch (wrapWidth)

{

case 64:

{

return [self base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];

}

case 76:

{

return [self base64EncodedStringWithOptions:NSDataBase64Encoding76CharacterLineLength];

}

default:

{

encoded = [self base64EncodedStringWithOptions:(NSDataBase64EncodingOptions)0];

}

if (!wrapWidth || wrapWidth >= [encoded length])

{

return encoded;

}

wrapWidth = (wrapWidth / 4) * 4;

NSMutableString *result = [NSMutableString string];

for (NSUInteger i = 0; i < [encoded length]; i+= wrapWidth)

{

if (i + wrapWidth >= [encoded length])

{

[result appendString:[encoded substringFromIndex:i]];

break;

}

[result appendString:[encoded substringWithRange:NSMakeRange(i, wrapWidth)]];

[result appendString:@"\r\n"];

}

return result;

}

/**

* @brief NSData转string 换行长度默认64

- (NSString *)base64EncodedString

{

return [self base64EncodedStringWithWrapWidth:0];

}

63、AES加密

#import

@interface NSData (AES)

/**

* 利用AES加密数据

- (NSData*)encryptedWithAESUsingKey:(NSString*)key andIV:(NSData*)iv {

NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding];

size_t dataMoved;

NSMutableData *encryptedData = [NSMutableData dataWithLength:self.length + kCCBlockSizeAES128];

CCCryptorStatus status = CCCrypt(kCCEncrypt,kCCAlgorithmAES128,kCCOptionPKCS7Padding,keyData.bytes,keyData.length,iv.bytes,self.bytes,self.length,encryptedData.mutableBytes, encryptedData.length,&dataMoved);

if (status == kCCSuccess) {

encryptedData.length = dataMoved;

return encryptedData;

}

return nil;

}

/**

* @brief 利用AES解密据

- (NSData*)decryptedWithAESUsingKey:(NSString*)key andIV:(NSData*)iv {

NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding];

size_t dataMoved;

NSMutableData *decryptedData = [NSMutableData dataWithLength:self.length + kCCBlockSizeAES128];

CCCryptorStatus result = CCCrypt(kCCDecrypt,kCCAlgorithmAES128,kCCOptionPKCS7Padding,keyData.bytes,keyData.length,iv.bytes,self.bytes,self.length,decryptedData.mutableBytes, decryptedData.length,&dataMoved);

if (result == kCCSuccess) {

decryptedData.length = dataMoved;

return decryptedData;

}

return nil;

}

最后编辑于：2018.02.01 09:24:52

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