TextView表情文字混排

- (void)layoutSubviews {
    
    skContentView.backgroundColor = self.backgroundColor;
    skContentView.frame = self.bounds;
    
    NSMutableAttributedString * string = [[ NSMutableAttributedString alloc ] initWithString:@"123456789101112计算"  attributes:nil ] ;
    [string addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:16.0] range:NSMakeRange(0,string.length-1)];
    
    MMTextAttachment * textAttachment = [[ MMTextAttachment alloc ] initWithData:nil ofType:nil ] ;
    UIImage * smileImage = [ UIImage imageNamed:@"a.jpg" ]  ;  //my emoticon image named a.jpg
    textAttachment.image = smileImage ;
    
    NSAttributedString * textAttachmentString = [ NSAttributedString attributedStringWithAttachment:textAttachment ] ;
    [ string insertAttributedString:textAttachmentString atIndex:6 ] ;
    
    _skInputTextView.attributedText = string ;
}

@interface MMTextAttachment : NSTextAttachment {
    
}

@end

@implementation MMTextAttachment

//图片大小与文字保持一致
- (CGRect)attachmentBoundsForTextContainer:(NSTextContainer *)textContainer proposedLineFragment:(CGRect)lineFrag glyphPosition:(CGPoint)position characterIndex:(NSUInteger)charIndex NS_AVAILABLE_IOS(7_0) {
    
    return CGRectMake( 0 , 0 , lineFrag.size.height , lineFrag.size.height );
}

@end