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iOS开发经验总结
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NSInvocationSEL 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 0x100000000double 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 = http://www.mamicode.com/[NSMutableData data]; UIGraphicsBeginPDFContextToData(pdfData, aView.bounds, nil); UIGraphicsBeginPDFPage(); CGContextRef pdfContext = UIGraphicsGetCurrentContext();"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yesBOOL 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=Aboutprefs:root=General&path=ACCESSIBILITYprefs:root=AIRPLANE_MODEprefs:root=General&path=AUTOLOCKprefs:root=General&path=USAGE/CELLULAR_USAGEprefs:root=Brightnessprefs:root=Bluetoothprefs:root=General&path=DATE_AND_TIMEprefs:root=FACETIMEprefs:root=Generalprefs:root=General&path=Keyboardprefs:root=CASTLEprefs:root=CASTLE&path=STORAGE_AND_BACKUPprefs:root=General&path=INTERNATIONALprefs:root=LOCATION_SERVICESprefs:root=ACCOUNT_SETTINGSprefs:root=MUSICprefs:root=MUSIC&path=EQprefs:root=MUSIC&path=VolumeLimitprefs:root=General&path=Networkprefs:root=NIKE_PLUS_IPODprefs:root=NOTESprefs:root=NOTIFICATIONS_IDprefs:root=Phoneprefs:root=Photosprefs:root=General&path=ManagedConfigurationListprefs:root=General&path=Resetprefs:root=Sounds&path=Ringtoneprefs:root=Safariprefs:root=General&path=Assistantprefs:root=Soundsprefs:root=General&path=SOFTWARE_UPDATE_LINKprefs:root=STOREprefs:root=TWITTERprefs:root=FACEBOOKprefs:root=General&path=USAGE prefs:root=VIDEOprefs:root=General&path=Network/VPNprefs:root=Wallpaperprefs:root=WIFIprefs:root=INTERNET_TETHERINGprefs:root=Phone&path=Blockedprefs: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 = http://www.mamicode.com/100;>
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]]; }
iOS开发经验总结