iOS textView 渲染html富文本&计算高度&图片适配
2019-08-08 本文已影响0人
iOS_July
-
先看效果：
text.gif
- 两个关键方法，传参时记得统一，也可以自己略作调整
/**
html 富文本设置
@param str html 未处理的字符串
@param font 设置字体
@param lineSpacing 设置行高
@return 默认不将 \n替换<br/> 返回处理好的富文本
*/
-(NSMutableAttributedString *)setAttributedString:(NSString *)str font:(UIFont *)font lineSpacing:(CGFloat)lineSpacing
{
//如果有换行，把\n替换成<br/>
//如果有需要把换行加上
// str = [str stringByReplacingOccurrencesOfString:@"\n" withString:@"<br/>"];
//设置HTML图片的宽度
str = [NSString stringWithFormat:@"<head><style>img{width:%f !important;height:auto}</style></head>%@",[UIScreen mainScreen].bounds.size.width,str];
NSMutableAttributedString *htmlString =[[NSMutableAttributedString alloc] initWithData:[str dataUsingEncoding:NSUTF8StringEncoding] options:@{NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType, NSCharacterEncodingDocumentAttribute:[NSNumber numberWithInt:NSUTF8StringEncoding]} documentAttributes:NULL error:nil];
//设置富文本字的大小
[htmlString addAttributes:@{NSFontAttributeName:font} range:NSMakeRange(0, htmlString.length)];
//设置行间距
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
[paragraphStyle setLineSpacing:lineSpacing];
[htmlString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0, [htmlString length])];
return htmlString;
}
/**
计算html字符串高度
@param str html 未处理的字符串
@param font 字体设置
@param lineSpacing 行高设置
@param width 容器宽度设置
@return 富文本高度
*/
-(CGFloat )getHTMLHeightByStr:(NSString *)str font:(UIFont *)font lineSpacing:(CGFloat)lineSpacing width:(CGFloat)width
{
// str = [str stringByReplacingOccurrencesOfString:@"\n" withString:@"<br/>"];
str = [NSString stringWithFormat:@"<head><style>img{width:%f !important;height:auto}</style></head>%@",[UIScreen mainScreen].bounds.size.width,str];
NSMutableAttributedString *htmlString =[[NSMutableAttributedString alloc] initWithData:[str dataUsingEncoding:NSUTF8StringEncoding] options:@{NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType, NSCharacterEncodingDocumentAttribute:[NSNumber numberWithInt:NSUTF8StringEncoding]} documentAttributes:NULL error:nil];
[htmlString addAttributes:@{NSFontAttributeName:font} range:NSMakeRange(0, htmlString.length)];
//设置行间距
NSMutableParagraphStyle *paragraphStyle1 = [[NSMutableParagraphStyle alloc] init];
[paragraphStyle1 setLineSpacing:lineSpacing];
[htmlString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle1 range:NSMakeRange(0, [htmlString length])];
CGSize contextSize = [htmlString boundingRectWithSize:(CGSize){width, CGFLOAT_MAX} options:NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading context:nil].size;
return contextSize.height ;
}
- 使用：
CGFloat detailY = CGRectGetMaxY(self.padView.frame);
NSAttributedString *attributedString = [self setAttributedString:self.model.Details font:kHMFont(16) lineSpacing:Height_Real(10)];
CGFloat textHeight = [self getHTMLHeightByStr:self.model.Details font:kHMFont(16) lineSpacing:Height_Real(10) width:SCREEN_WIDTH];
UITextView *detailView = [[UITextView alloc]initWithFrame:CGRectMake(0, detailY, SCREEN_WIDTH, textHeight)];
detailView.attributedText = attributedString;
detailView.scrollEnabled = NO;
detailView.editable = NO;
[self.scrollView addSubview:detailView];
