oc_calculate_label_text_in_single_line.codesnippest

oc_calculate_label_text_in_single_line.codesnippest

//
//  UILabel+LSFrame.m
//  iLawSchool
//
//  Created by ljtwan on 2018/8/30.
//  Copyright © 2018 iCourt. All rights reserved.
//

#import "UILabel+LSFrame.h"
#import <CoreText/CoreText.h>

@implementation UILabel (LSFrame)
- (NSUInteger)textLines {
    return [self getLinesArrayOfString].count;
}

- (NSUInteger)maxHeight {
    // 一行的高度
    self.numberOfLines = 0;
    CGFloat labelHeight = [self sizeThatFits:CGSizeMake(self.frame.size.width, CGFLOAT_MAX)].height;
    return labelHeight;
}

- (NSArray *)getLinesArrayOfString {
    NSString *text = [self text];
    if (!text) {
        return @[];
    }
    UIFont *font = [self font];
    CGRect rect = [self frame];
    
    CTFontRef myFont = CTFontCreateWithName(( CFStringRef)([font fontName]), [font pointSize], NULL);
    NSMutableAttributedString *attStr = [[NSMutableAttributedString alloc] initWithString:text];
    [attStr addAttribute:(NSString *)kCTFontAttributeName value:(__bridge  id)myFont range:NSMakeRange(0, attStr.length)];
    CFRelease(myFont);
    CTFramesetterRef frameSetter = CTFramesetterCreateWithAttributedString(( CFAttributedStringRef)attStr);
    CGMutablePathRef path = CGPathCreateMutable();
    CGPathAddRect(path, NULL, CGRectMake(0,0,rect.size.width,100000));
    CTFrameRef frame = CTFramesetterCreateFrame(frameSetter, CFRangeMake(0, 0), path, NULL);
    NSArray *lines = ( NSArray *)CTFrameGetLines(frame);
    NSMutableArray *linesArray = [[NSMutableArray alloc]init];
    for (id line in lines) {
        CTLineRef lineRef = (__bridge  CTLineRef )line;
        CFRange lineRange = CTLineGetStringRange(lineRef);
        NSRange range = NSMakeRange(lineRange.location, lineRange.length);
        NSString *lineString = [text substringWithRange:range];
        CFAttributedStringSetAttribute((CFMutableAttributedStringRef)attStr, lineRange, kCTKernAttributeName, (CFTypeRef)([NSNumber numberWithFloat:0.0]));
        CFAttributedStringSetAttribute((CFMutableAttributedStringRef)attStr, lineRange, kCTKernAttributeName, (CFTypeRef)([NSNumber numberWithInt:0.0]));
        [linesArray addObject:lineString];
    }
    
    CGPathRelease(path);
    CFRelease( frame );
    CFRelease(frameSetter);
    return (NSArray *)linesArray;
}

@end