yytext超过固定行数，显示查看更多按钮

#import "ViewController.h"

#import

#import

#import

@interface ViewController ()

@property(nonatomic,strong)YYLabel *label;

@end

@implementation ViewController

- (void)viewDidLoad {

    [super viewDidLoad];

    // Do any additional setup after loading the view, typically from a nib.

    NSMutableAttributedString *text = [NSMutableAttributedString new];

    UIFont*font = [UIFontsystemFontOfSize:16];

    NSString *title = @"dwwdqwddqdqdqdqwdqdqwdqwdqdqdqdqwdqwdqdqdqwdqdqwdqdqdqdqdqdqwdq当前dwwdqwddqdqdqdqwdqdqwdqwdqdqdqdqwdqwdqdqdqwdqdqwdqdqdqdqdqdqwdq当前dwwdqwddqdqdqdqwdqdqwdqwdqdqdqdqwdqwdqdqdqwdqdqwdqdqdqdqdqdqwdq当前dwwdqwddqdqdqdqwdqdqwdqwdqdqdqdqwdqwdqdqdqwdqdqwdqdqdqdqdqdqwdq当前dwwdqwddqdqdqdqwdqdqwdqwdqdqdqdqwdqwdqdqdqwdqdqwdqdqdqdqdqdqwdq当前";

    [textappendAttributedString:[[NSAttributedString alloc] initWithString:title attributes:nil]];

    text.yy_font= font ;

    _label= [YYLabelnew];

    _label.userInteractionEnabled = YES;

    _label.numberOfLines = 0;

    _label.textVerticalAlignment = YYTextVerticalAlignmentTop;

    _label.frame = CGRectMake(40,60, self.view.frame.size.width-80,60);

    _label.attributedText = text;

    [self.view addSubview:_label];

    _label.layer.borderWidth = 0.5;

    _label.layer.borderColor = [UIColor colorWithRed:0.000 green:0.463 blue:1.000 alpha:1.000].CGColor;

    // 添加全文

    [self addSeeMoreButton];

}

#pragma mark - 添加全文

- (void)addSeeMoreButton {

    __weak __typeof(self) weakSelf = self;

    NSMutableAttributedString *text = [[NSMutableAttributedString alloc] initWithString:@"...全文"];

    YYTextHighlight *hi = [YYTextHighlight new];

    [hisetColor:[UIColor colorWithRed:0.578 green:0.790 blue:1.000 alpha:1.000]];

    hi.tapAction= ^(UIView*containerView,NSAttributedString*text,NSRangerange,CGRectrect) {

        // 点击全文回调

//        YYLabel *label = weakSelf.label;

//        [label sizeToFit];

        NSLog(@"点击yytext问题");

    };

    [textyy_setColor:[UIColor colorWithRed:0.000 green:0.449 blue:1.000 alpha:1.000] range:[text.string rangeOfString:@"全文"]];

    [textyy_setTextHighlight:hi range:[text.string rangeOfString:@"全文"]];

    text.yy_font=_label.font;

    YYLabel*seeMore = [YYLabelnew];

    seeMore.attributedText= text;

    [seeMoresizeToFit];

    NSAttributedString *truncationToken = [NSAttributedString yy_attachmentStringWithContent:seeMore contentMode:UIViewContentModeCenter attachmentSize:seeMore.frame.size alignToFont:text.yy_font alignment:YYTextVerticalAlignmentCenter];

    _label.truncationToken= truncationToken;

}