ios 基础知识点总结

Posted Eric博客

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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

Untitled.gif

 

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/mach.h>
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 <CoreLocation/CoreLocation.h>
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 = @"<h1>Header</h1><h2>Subheader</h2><p>Some <em>text</em></p>![](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 <= 'z') ||
                   (thisChar >= 'A' && thisChar <= 'Z') ||
                   (thisChar >= '0' && thisChar <= '9')) 
            [output appendFormat:@"%c", thisChar];
         else 
            [output appendFormat:@"%%%02X", 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:@"%02X", 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 <CommonCrypto/CommonCryptor.h>
@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;

64、3DES加密

#import <CommonCrypto/CommonCryptor.h>
@interface NSData (3DES)
/**
 *  利用3DES加密数据
 */
- (NSData*)encryptedWith3DESUsingKey:(NSString*)key andIV:(NSData*)iv 

    NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding];

    size_t dataMoved;
    NSMutableData *encryptedData = [NSMutableData dataWithLength:self.length + kCCBlockSize3DES];

    CCCryptorStatus result = CCCrypt(kCCEncrypt,kCCAlgorithm3DES,kCCOptionPKCS7Padding,keyData.bytes,keyData.length,iv.bytes,self.bytes,self.length,encryptedData.mutableBytes,encryptedData.length,&dataMoved);

    if (result == kCCSuccess) 
        encryptedData.length = dataMoved;
        return encryptedData;
    

    return nil;


/**
 *  @brief   利用3DES解密数据
 */
- (NSData*)decryptedWith3DESUsingKey:(NSString*)key andIV:(NSData*)iv 

    NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding];

    size_t dataMoved;
    NSMutableData *decryptedData = [NSMutableData dataWithLength:self.length + kCCBlockSize3DES];

    CCCryptorStatus result = CCCrypt(kCCDecrypt,kCCAlgorithm3DES,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;

65、单个页面多个网络请求的情况,需要监听所有网络请求结束后刷新UI

dispatch_group_t group = dispatch_group_create();
    dispatch_queue_t serialQueue = dispatch_queue_create("com.wzb.test.www", DISPATCH_QUEUE_SERIAL);
    dispatch_group_enter(group);
    dispatch_group_async(group, serialQueue, ^
        // 网络请求一
        [WebClick getDataSuccess:^(ResponseModel *model) 
            dispatch_group_leave(group);
         failure:^(NSString *err) 
            dispatch_group_leave(group);
        ];
    );
    dispatch_group_enter(group);
    dispatch_group_async(group, serialQueue, ^
        // 网络请求二
        [WebClick getDataSuccess:getBigTypeRM onSuccess:^(ResponseModel *model) 
            dispatch_group_leave(group);
                                          failure:^(NSString *errorString) 
            dispatch_group_leave(group);
        ];
    );
    dispatch_group_enter(group);
    dispatch_group_async(group, serialQueue, ^
        // 网络请求三
        [WebClick getDataSuccess:^
            dispatch_group_leave(group);
         failure:^(NSString *errorString) 
            dispatch_group_leave(group);
        ];
    );

    // 所有网络请求结束后会来到这个方法
    dispatch_group_notify(group, serialQueue, ^
        dispatch_async(dispatch_get_global_queue(0, 0), ^
            dispatch_async(dispatch_get_main_queue(), ^
                // 刷新UI
            );
        );
    );

66、解决openUrl延时问题

// 方法一
dispatch_async(dispatch_get_main_queue(), ^

    UIApplication *application = [UIApplication sharedApplication];
    if ([application respondsToSelector:@selector(openURL:options:completionHandler:)]) 
        [application openURL:URL options:@
           completionHandler:nil];
     else 
        [application openURL:URL];
    
    );
// 方法二
[self performSelector:@selector(redirectToURL:) withObject:url afterDelay:0.1];

- (void) redirectToURL

UIApplication *application = [UIApplication sharedApplication];
    if ([application respondsToSelector:@selector(openURL:options:completionHandler:)]) 
        [application openURL:URL options:@
           completionHandler:nil];
     else 
        [application openURL:URL];
    

67、页面跳转实现翻转动画

// modal方式
    TestViewController *vc = [[TestViewController alloc] init];
    vc.view.backgroundColor = [UIColor redColor];
    vc.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
    [self presentViewController:vc animated:YES completion:nil];

// push方式
    TestViewController *vc = [[TestViewController alloc] init];
    vc.view.backgroundColor = [UIColor redColor];
    [UIView beginAnimations:@"View Flip" context:nil];
    [UIView setAnimationDuration:0.80];
    [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
    [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight forView:self.navigationController.view cache:NO];
    [self.navigationController pushViewController:vc animated:YES];
    [UIView commitAnimations];

68、tableView实现无限滚动

- (void)scrollViewDidScroll:(UIScrollView *)scrollView

    CGFloat actualPosition = scrollView.contentOffset.y;
    CGFloat contentHeight = scrollView.contentSize.height - scrollView.frame.size.height;
    if (actualPosition >= contentHeight) 
        [self.dataArr addObjectsFromArray:self.dataArr];
        [self.tableView reloadData];
    

69、代码方式调整屏幕亮度

// brightness属性值在0-1之间,0代表最小亮度,1代表最大亮度
[[UIScreen mainScreen] setBrightness:0.5];

70、获取当前应用CUP用量

float cpu_usage()

    kern_return_t kr;
    task_info_data_t tinfo;
    mach_msg_type_number_t task_info_count;

    task_info_count = TASK_INFO_MAX;
    kr = task_info(mach_task_self(), TASK_BASIC_INFO, (task_info_t)tinfo, &task_info_count);
    if (kr != KERN_SUCCESS) 
        return -1;
    

    task_basic_info_t      basic_info;
    thread_array_t         thread_list;
    mach_msg_type_number_t thread_count;

    thread_info_data_t     thinfo;
    mach_msg_type_number_t thread_info_count;

    thread_basic_info_t basic_info_th;
    uint32_t stat_thread = 0; // Mach threads

    basic_info = (task_basic_info_t)tinfo;

    // get threads in the task
    kr = task_threads(mach_task_self(), &thread_list, &thread_count);
    if (kr != KERN_SUCCESS) 
        return -1;
    
    if (thread_count > 0)
        stat_thread += thread_count;

    long tot_sec = 0;
    long tot_usec = 0;
    float tot_cpu = 0;
    int j;

    for (j = 0; j < (int)thread_count; j++)
    
        thread_info_count = THREAD_INFO_MAX;
        kr = thread_info(thread_list[j], THREAD_BASIC_INFO,
                         (thread_info_t)thinfo, &thread_info_count);
        if (kr != KERN_SUCCESS) 
            return -1;
        

        basic_info_th = (thread_basic_info_t)thinfo;

        if (!(basic_info_th->flags & TH_FLAGS_IDLE)) 
            tot_sec = tot_sec + basic_info_th->user_time.seconds + basic_info_th->system_time.seconds;
            tot_usec = tot_usec + basic_info_th->user_time.microseconds + basic_info_th->system_time.microseconds;
            tot_cpu = tot_cpu + basic_info_th->cpu_usage / (float)TH_USAGE_SCALE * 100.0;
        

     // for each thread

    kr = vm_deallocate(mach_task_self(), (vm_offset_t)thread_list, thread_count * sizeof(thread_t));
    assert(kr == KERN_SUCCESS);

    return tot_cpu;

71、float数据取整四舍五入

    CGFloat f = 4.65;
    NSLog(@"%d", (int)f);    // 打印结果4

    CGFloat f = 4.65;
    NSLog(@"%d", (int)round(f));    // 打印结果5

72、删除UISearchBar系统默认边框

    // 方法一
    searchBar.searchBarStyle = UISearchBarStyleMinimal;

    // 方法二
    [searchBar setBackgroundImage:[[UIImage alloc]init]];

    // 方法三
    searchBar.barTintColor = [UIColor whiteColor];

73、为UICollectionViewCell设置圆角和阴影

cell.contentView.layer.cornerRadius = 2.0f;
cell.contentView.layer.borderWidth = 1.0f;
cell.contentView.layer.borderColor = [UIColor clearColor].CGColor;
cell.contentView.layer.masksToBounds = YES;

cell.layer.shadowColor = [UIColor lightGrayColor].CGColor;
cell.layer.shadowOffset = CGSizeMake(0, 2.0f);
cell.layer.shadowRadius = 2.0f;
cell.layer.shadowOpacity = 1.0f;
cell.layer.masksToBounds = NO;
cell.layer.shadowPath = [UIBezierPath bezierPathWithRoundedRect:cell.bounds cornerRadius:cell.contentView.layer.cornerRadius].CGPath;

74、让正在滑动的scrollView停止滚动(不是禁止,而是暂时停止滚动)

[scrollView setContentOffset:scrollView.contentOffset animated:NO];

75、使用xib设置UIView的边框、圆角

圆角和边框看下图即可设置

xib设置圆角边框.png

但是增加layer.borderColor的keyPath设置边框颜色并不能起作用,后来查了资料,这里应该用layer.borderUIColor,但是这里设置的颜色不起作用,无论设置什么颜色显示出来的都是黑色的。后来又去查了下,有种解决方案是给CALayer添加一个分类,提供一个 - (void)setBorderUIColor:(UIColor *)color;方法就可以解决了,实现如下:

xib设置边框颜色.png

#import "CALayer+BorderColor.h"

@implementation CALayer (BorderColor)

- (void)setBorderUIColor:(UIColor *)color

    self.borderColor = color.CGColor;

76、根据经纬度获取城市等信息

// 创建经纬度
    CLLocation *location = [[CLLocation alloc] initWithLatitude:latitude longitude:longitude];
    //创建一个译码器
    CLGeocoder *cLGeocoder = [[CLGeocoder alloc] init];
    [cLGeocoder reverseGeocodeLocation:userLocation completionHandler:^(NSArray *placemarks, NSError *error) 
        CLPlacemark *place = [placemarks objectAtIndex:0];
        // 位置名
      NSLog(@"name,%@",place.name);
      // 街道
      NSLog(@"thoroughfare,%@",place.thoroughfare);
      // 子街道
      NSLog(@"subThoroughfare,%@",place.subThoroughfare);
      // 市
      NSLog(@"locality,%@",place.locality);
      // 区
      NSLog(@"subLocality,%@",place.subLocality); 
      // 国家
      NSLog(@"country,%@",place.country);
        
    ];

/*  CLPlacemark中属性含义
name                    地名

thoroughfare            街道

subThoroughfare        街道相关信息,例如门牌等

locality                城市

subLocality            城市相关信息,例如标志性建筑

administrativeArea      直辖市

subAdministrativeArea  其他行政区域信息(自治区等)

postalCode              邮编

ISOcountryCode          国家编码

country                国家

inlandWater            水源,湖泊

ocean                  海洋

areasOfInterest        关联的或利益相关的地标
*/

77、如何防止添加多个NSNotification观察者?

// 解决方案就是添加观察者之前先移除下这个观察者
[[NSNotificationCenter defaultCenter] removeObserver:observer name:name object:object];
        [[NSNotificationCenter defaultCenter] addObserver:observer selector:selector name:name object:object];

78、将一个xib添加到另外一个xib上

// 假设你的自定义view名字为CustomView,你需要在CustomView.m中重写 `- (instancetype)initWithCoder:(NSCoder *)aDecoder` 方法,代码如下:
- (instancetype)initWithCoder:(NSCoder *)aDecoder 
    if ((self = [super initWithCoder:aDecoder])) 
        [self addSubview:[[[NSBundle mainBundle] loadNibNamed:@"CustomView" owner:self options:nil] objectAtIndex:0]];
    
    return self;

将一个xib添加到另外一个xib上.png

79、处理字符串,使其首字母大写

    NSString *str = @"abcdefghijklmn";
    NSString *resultStr;
    if (str && str.length > 0) 
        resultStr = [str stringByReplacingCharactersInRange:NSMakeRange(0,1) withString:[[str substringToIndex:1] capitalizedString]];
    
    NSLog(@"%@", resultStr);

80、判断一个UIAlertView/UIAlertController是否显示

// UIAlertView自带属性
if (alert.visible)

      NSLog(@"显示了");
 else 
      NSLog(@"未显示");


// UIAlertController没有visible属性,需要自己判断,添加一个全局变量 BOOL visible
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Title" message:@"message" preferredStyle:UIAlertControllerStyleAlert];
    UIAlertAction *alertAction = [UIAlertAction actionWithTitle:@"ActionTitle" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) 
        self.visible = NO;
    ];
    UIAlertAction *calcelAction = [UIAlertAction actionWithTitle:@"calcelTitle" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) 
        self.visible = NO;
    ];
    [alertController addAction:alertAction];
    [alertController addAction:calcelAction];
    [self presentViewController:alertController animated:YES completion:^
        self.visible = YES;
    ];

81、获取字符串中的数字

- (NSString *)getNumberFromStr:(NSString *)str

    NSCharacterSet *nonDigitCharacterSet = [[NSCharacterSet decimalDigitCharacterSet] invertedSet];
    return [[str componentsSeparatedByCharactersInSet:nonDigitCharacterSet] componentsJoinedByString:@""];


    NSLog(@"%@", [self getNumberFromStr:@"a0b0c1d2e3f4fda8fa8fad9fsad23"]); // 00123488923

82、为UIView的某个方向添加边框

// 添加UIView分类

// UIView+WZB.h
#import <UIKit/UIKit.h> 
/** 边框方向 - WZBBorderDirectionTop: 顶部 - WZBBorderDirectionLeft: 左边 - WZBBorderDirectionBottom: 底部 - WZBBorderDirectionRight: 右边 */ 

typedef NS_ENUM(NSInteger, WZBBorderDirectionType)  
WZBBorderDirectionTop = 0, 
WZBBorderDirectionLeft, 
WZBBorderDirectionBottom, 
WZBBorderDirectionRight 
; 
@interface UIView (WZB) 

/** 为UIView的某个方向添加边框 @param direction 边框方向 @param color 边框颜色 @param width 边框宽度 */ 

- (void)wzb_addBorder:(WZBBorderDirectionType)direction color:(UIColor *)color width:(CGFloat)width; 
@end 

// UIView+WZB.m 
#import "UIView+WZB.h"
 @implementation UIView (WZB)
- (void)wzb_addBorder:(WZBBorderDirectionType)direction color:(UIColor *)color width:(CGFloat)width  
CALayer *border = [CALayer layer]; 
border.backgroundColor = color.CGColor; 
switch (direction)  
    case WZBBorderDirectionTop:  
        border.frame = CGRectMake(0.0f, 0.0f, self.bounds.size.width, width); 
     break; 
    case WZBBorderDirectionLeft:  
        border.frame = CGRectMake(0.0f, 0.0f, width, self.bounds.size.height); 
     break; 
    case WZBBorderDirectionBottom:  
        border.frame = CGRectMake(0.0f, self.bounds.size.height - width, self.bounds.size.width, width); 
     break; 
    case WZBBorderDirectionRight:  
        border.frame = CGRectMake(self.bounds.size.width - width, 0, width, self.bounds.size.height);
      break; 
    default: break;
  
[self.layer addSublayer:border]; 






 

83、通过属性设置UISwitch、UIProgressView等控件的宽高

mySwitch.transform = CGAffineTransformMakeScale(5.0f, 5.0f);

progressView.transform = CGAffineTransformMakeScale(5.0f, 5.0f);

84、自动搜索功能,用户连续输入的时候不搜索,用户停止输入的时候自动搜索(我这里设置的是0.5s,可根据需求更改)

// 输入框文字改变的时候调用
-(void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText
    // 先取消调用搜索方法
    [NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(searchNewResult) object:nil];
    // 0.5秒后调用搜索方法
    [self performSelector:@selector(searchNewResult) withObject:nil afterDelay:0.5];

85、修改UISearchBar的占位文字颜色

    // 方法一(推荐使用)
    UITextField *searchField = [searchBar valueForKey:@"_searchField"];
    [searchField setValue:[UIColor blueColor] forKeyPath:@"_placeholderLabel.textColor"];

    // 方法二(已过期)
    [[UILabel appearanceWhenContainedIn:[UISearchBar class], nil] setTextColor:[UIColor redColor]];

    // 方法三(已过期)
    NSDictionary *placeholderAttributes = @NSForegroundColorAttributeName : [UIColor redColor], NSFontAttributeName : [UIFont fontWithName:@"HelveticaNeue" size:15],;
    NSAttributedString *attributedPlaceholder = [[NSAttributedString alloc] initWithString:searchBar.placeholder attributes:placeholderAttributes];
    [[UITextField appearanceWhenContainedIn:[UISearchBar class], nil] setAttributedPlaceholder:attributedPlaceholder];

86、某个界面多个事件同时响应引起的问题(比如,两个button同时按push到新界面,两个都会响应,可能导致push重叠)

// UIView有个属性叫做exclusiveTouch,设置为YES后,其响应事件会和其他view互斥(有其他view事件响应的时候点击它不起作用)
view.exclusiveTouch = YES;

// 一个一个设置太麻烦了,可以全局设置
[[UIView appearance] setExclusiveTouch:YES];

// 或者只设置button
[[UIButton appearance] setExclusiveTouch:YES];

87、修改tabBar的frame

// 子类化UITabBarViewController,我这里以修改tabBar高度为例,重写viewWillLayoutSubviews方法


#import "WZBTabBarViewController.h" 
@interface WZBTabBarViewController () 
@end 
@implementation WZBTabBarViewController 
- (void)viewWillLayoutSubviews  
CGRect tabFrame  = self.tabBar.frame; 
tabFrame.size.height = 100; 
tabFrame.origin.y = self.view.frame.size.height - 100; 
self.tabBar.frame = tabFrame; 

 @end

 

88、修改键盘背景颜色

// 设置某个键盘颜色
    textField.keyboardAppearance = UIKeyboardAppearanceAlert;

// 设置工程中所有键盘颜色
[[UITextField appearance] setKeyboardAppearance:UIKeyboardAppearanceAlert];

89、修改image颜色

UIImage *image = [UIImage imageNamed:@"test"];
    imageView.image = [image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
    CGRect rect = CGRectMake(0, 0, image.size.width, image.size.height);
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextClipToMask(context, rect, image.CGImage);
    CGContextSetFillColorWithColor(context, [[UIColor redColor] CGColor]);
    CGContextFillRect(context, rect);
    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImag

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