iOS文本实现超链接

柔情只为你懂 2023-10-17 15:43 15阅读 0赞

[Demo下载地址][Demo]

在做登录或者注册页面时，都会有有类似于协议阅读的功能，左边是一个选择框是否阅读，右边是一行文本，且协议文本颜色不同。

之前在做的时候，因为一行文本就能显示全，且仅仅只是一个协议，因此博主采取的方法如下：

1、在label覆盖一个clearColor的UIButton，坐标同label大小

2、给label上添加一个UITapGestureRecognizer手势

但后期有些功能牵扯到金融以及安全问题，需要多个协议以及多行显示，这时要按之前方法去做的话，就需要截取当前文本协议长度以及位置，然后在相应位置上添加buton和手势，做起来还是相对麻烦一下。因此博主想法用文本实现超链接那种方式百度一下，找到UITextView的一个代理方法，且这种方法能将前面的勾选框也显示在富文本之前，但是自我感觉没有直接创建UIImageView或者UIButton使用起来灵活，因为我们可以将UIButton的frame放大，手指触摸面积增大

\- (BOOL)textView:(UITextView \*)textView shouldInteractWithURL:(NSURL \*)URL inRange:(NSRange)characterRange

PS：UILabel控件是没有这个代理方法的，因此只能创建添加UITextView。

1、首先我们要设置富文本以及添加链接

- (void)viewDidLoad {
        [super viewDidLoad];
        
        self.select = NO;
        
        [self setSubView];//设置子view
        [self setLinkText];//设置文本
    }
    
    //设置子view
    - (void)setSubView{
        UIFont *linkFont = [UIFont systemFontOfSize:14.0];
        CGFloat linkW = ScreenWidth - 10*2;
        
        UITextView *linkTV = [[UITextView alloc]initWithFrame:CGRectMake(10, 100, linkW, 100)];
        self.linkTV = linkTV;
        linkTV.userInteractionEnabled = YES;
        linkTV.font = linkFont;
        linkTV.textColor = UIColorFromRGB(0x999999,1.0);
        [self.view addSubview:linkTV];
        linkTV.editable = NO;//必须禁止输入，否则点击将弹出输入键盘
        linkTV.scrollEnabled = NO;
        linkTV.delegate = self;
        linkTV.textContainerInset = UIEdgeInsetsMake(0,0, 0, 0);//文本距离边界值
    }
    
    //设置文本
    - (void)setLinkText{
        NSString *linkStr = @"我已阅读《登录协议》和《注册协议》，并且还有《支付宝支付协议》、《微信支付协议》，《中国工商银行协议》、《中国银行协议》、《中国建设银行协议》、《中国农业银行协议》";
        UIFont *linkFont = [UIFont systemFontOfSize:14.0];
        CGFloat linkW = ScreenWidth - 10*2;
        CGSize linkSize = [self getAttributionHeightWithString:linkStr lineSpace:1.5 kern:1 font:linkFont width:linkW];
        self.linkTV.frame = CGRectMake(10, 100, linkW, linkSize.height);
        
        NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:linkStr];
        [attributedString addAttribute:NSLinkAttributeName value:@"login://" range:[[attributedString string] rangeOfString:@"《登录协议》"]];
        [attributedString addAttribute:NSLinkAttributeName value:@"register://" range:[[attributedString string] rangeOfString:@"《注册协议》"]];
        
        CGSize size = CGSizeMake(12, 12);
        UIImage *image = [UIImage imageNamed:self.select == YES ? @"selected" : @"unSelected"];
        UIGraphicsBeginImageContextWithOptions(size, false, 0);
        [image drawInRect:CGRectMake(0, 0.25, 12, 12)];
        UIImage *resizeImage = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();
        NSTextAttachment *textAttachment = [[NSTextAttachment alloc] init];
        textAttachment.image = resizeImage;
        NSMutableAttributedString *imageString = (NSMutableAttributedString *)[NSMutableAttributedString attributedStringWithAttachment:textAttachment];
        [imageString addAttribute:NSLinkAttributeName value:@"checkbox://" range:NSMakeRange(0, imageString.length)];
        [attributedString insertAttributedString:imageString atIndex:0];
    //    [attributedString addAttribute:NSFontAttributeName value:linkFont range:NSMakeRange(0, attributedString.length)];
        
        NSMutableParagraphStyle *paragraphStyle = [NSMutableParagraphStyle new];
        //调整行间距
        paragraphStyle.lineSpacing = 1.5;
        NSDictionary *attriDict = @{NSParagraphStyleAttributeName:paragraphStyle,NSKernAttributeName:@(1),
                                    NSFontAttributeName:linkFont};
        [attributedString addAttributes:attriDict range:NSMakeRange(0, attributedString.length)];
        
        self.linkTV.attributedText = attributedString;
        self.linkTV.linkTextAttributes = @{NSForegroundColorAttributeName: [UIColor blueColor], NSUnderlineColorAttributeName: [UIColor lightGrayColor], NSUnderlineStyleAttributeName: @(NSUnderlinePatternSolid)};
    }
    
    /*
     *  设置行间距和字间距
     *
     *  @param string    字符串
     *  @param lineSpace 行间距
     *  @param kern      字间距
     *  @param font      字体大小
     *
     *  @return 富文本
     */
    - (NSAttributedString *)getAttributedWithString:(NSString *)string WithLineSpace:(CGFloat)lineSpace kern:(CGFloat)kern font:(UIFont *)font{
        NSMutableParagraphStyle *paragraphStyle = [NSMutableParagraphStyle new];
        //调整行间距
        paragraphStyle.lineSpacing = lineSpace;
        NSDictionary *attriDict = @{NSParagraphStyleAttributeName:paragraphStyle,NSKernAttributeName:@(kern),
                                    NSFontAttributeName:font};
        NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc]initWithString:string attributes:attriDict];
        return attributedString;
    }
    
    /* 获取富文本的高度
     *
     * @param string    文字
     * @param lineSpace 行间距
     * @param kern      字间距
     * @param font      字体大小
     * @param width     文本宽度
     *
     * @return size
     */
    - (CGSize)getAttributionHeightWithString:(NSString *)string lineSpace:(CGFloat)lineSpace kern:(CGFloat)kern font:(UIFont *)font width:(CGFloat)width {
        NSMutableParagraphStyle *paragraphStyle = [NSMutableParagraphStyle new];
        paragraphStyle.lineSpacing = lineSpace;
        NSDictionary *attriDict = @{
                                    NSParagraphStyleAttributeName:paragraphStyle,
                                    NSKernAttributeName:@(kern),
                                    NSFontAttributeName:font};
        CGSize size = [string boundingRectWithSize:CGSizeMake(width, MAXFLOAT) options:NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading attributes:attriDict context:nil].size;
        return size;
    }

2、响应UITextView的代理方法，类似于UIButton的点击事件

- (BOOL)textView:(UITextView *)textView shouldInteractWithURL:(NSURL *)URL inRange:(NSRange)characterRange {
        if ([[URL scheme] isEqualToString:@"checkbox"]) {
            self.view.backgroundColor = [UIColor whiteColor];
            self.select = !self.select;
            [self setLinkText];//设置文本
            return NO;
        }else if ([[URL scheme] isEqualToString:@"login"]) {
            self.view.backgroundColor = [UIColor redColor];
            return NO;
        }else if ([[URL scheme] isEqualToString:@"register"]) {
            self.view.backgroundColor = [UIColor greenColor];
            return NO;
        }
        return YES;
    }

效果如下：

![Center][]

参考文章

[http://www.jianshu.com/p/480db0cc7380][http_www.jianshu.com_p_480db0cc7380]

[Demo]: https://github.com/RookieForMingge/LinkTextAttributes
[Center]: https://img-blog.csdn.net/20170908144419961?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvTWluZ2dlUWluZ2NodW4=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center
[http_www.jianshu.com_p_480db0cc7380]: http://www.jianshu.com/p/480db0cc7380