iOS如何封装带复制功能的UILabel示例代码

2020-07-26 02:24:22

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前言

UILabel继承自UIView是iOS中使用非常频繁的一个视图控件一般用于显示文字。

一：基本使用

1.创建

UILabel *label = [[UILabel alloc]initWithFrame:CGRectMake(20, 64, 100, 30)];[self.view addSubview:label];

2.属性设置

在iOS中你想要使用一个属性一般就直接“.”属性英文名称，或者“set”属性英文名称一般就可以出现

label.backgroundColor = [UIColor yellowColor];//设置背景颜色label.textColor = [UIColor redColor];//设置Label上文字的颜色label.text = @"我是一个UILabel";//设置Label上的文字label.font = [UIFont systemFontOfSize:15];//设置Label上文字的大小 默认为17label.textAlignment = NSTextAlignmentCenter;//设置文字位子默认靠左label.numberOfLines = 0;//设置行数默认为1，当为0时可以就是设置多行label.font = [UIFont fontWithName:@"Arial" size:30];//设置内容字体和字体大小label.highlighted = YES;//Label是否高亮//有时偶尔会使用到阴影设置label.shadowColor = [UIColor blueColor];//设置阴影颜色label.shadowOffset = CGSizeMake(10, 10);//设置阴影的偏移

二、在iOS中下面三个控件，自身就有复制-粘贴的功能：

1、UITextView

2、UITextField

3、UIWebView

在iOS8 之后, 我们发现UILabel不在为我们提供长按弹出复制等操作了, 我们来继承UILabel自己写一个带复制功能的UILabel

三、废话少说，直接撸代码

#import "CopyLabel.h"@implementation CopyLabel- (instancetype)initWithFrame:(CGRect)frame { if (self = [super initWithFrame:frame]) { [self pressAction]; } return self;}// 初始化设置- (void)pressAction { self.userInteractionEnabled = YES; UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPressAction:)]; longPress.minimumPressDuration = 0.25; [self addGestureRecognizer:longPress];}// 使label能够成为响应事件- (BOOL)canBecomeFirstResponder {  return YES;}// 自定义方法时才显示对就选项菜单，即屏蔽系统选项菜单- (BOOL)canPerformAction:(SEL)action withSender:(id)sender { if (action == @selector(customCopy:)){  return YES; } return NO;}- (void)customCopy:(id)sender { UIPasteboard *pasteboard = [UIPasteboard generalPasteboard]; pasteboard.string = self.text;}- (void)longPressAction:(UIGestureRecognizer *)recognizer { if (recognizer.state == UIGestureRecognizerStateBegan) { [self becomeFirstResponder]; UIMenuItem *copyItem = [[UIMenuItem alloc] initWithTitle:@"拷贝" action:@selector(customCopy:)]; UIMenuController *menuController = [UIMenuController sharedMenuController]; menuController.menuItems = [NSArray arrayWithObjects:copyItem, nil]; [menuController setTargetRect:self.frame inView:self.superview]; [menuController setMenuVisible:YES animated:YES]; }}@end

四、废话少说，直接看效果

- (void)viewDidLoad { [super viewDidLoad]; CopyLabel *copy = [[CopyLabel alloc] initWithFrame:CGRectMake(0, 100, [UIScreen mainScreen].bounds.size.width,50)]; copy.text = @"清明时节雨纷纷，路上行人欲断魂。"; copy.textAlignment = NSTextAlignmentCenter; copy.backgroundColor = [UIColor yellowColor]; copy.textColor = [UIColor redColor]; copy.font = [UIFont boldSystemFontOfSize:16]; [self.view addSubview:copy];}