有非常多时候。UITableViewCell每行的高度是不固定的，须要动态设置。
UITableView有个代理方法，
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{
return ((CZWeiboFrame*)[self.weiboFrames objectAtIndex:indexPath.row]).rowHeight;
}有的会想在这里先获取cell。然后过去cell的高度再返回，可是这是不可行的，由于上述方法会在
下述方法之前运行。
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
CZWeiboFrame *model = self.weiboFrames[indexPath.row] ;
static NSString *identifer = @"weibo";
CZWeiboCell *cell = [tableView dequeueReusableCellWithIdentifier:identifer];
if(cell == nil){
cell = [[CZWeiboCell alloc ] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:identifer];
}
cell.weiboFrame = model;
return cell;
}也就是说在你获取cell之前必须先设置cell的高度。
那么该怎么做呢。那就得在你给cell设置数据时，如今数据模型中计算出高度。
以下是上述代码中CZWeiboViewCell模型的结构
@interface CZWeiboFrame : NSObject @property (nonatomic,strong) CZWeibo *weibo; @property (nonatomic,assign,readonly) CGRect iconFrame; @property (nonatomic,assign,readonly) CGRect textFrame; @property (nonatomic,assign,readonly) CGRect nameFrame; @property (nonatomic,assign,readonly) CGRect pictureFrame; @property (nonatomic,assign,readonly) CGRect vipFrame; @property (nonatomic,assign,readonly) CGFloat rowHeight; @end当中weibo是每行要显示的数据。row height是行高，其余是cell中每一个控件的frame,在weibo的set方法中计算frame
-(void)setWeibo:(CZWeibo *)weibo{
_weibo = weibo;
CGFloat margin = 10;
CGFloat iconW = 35;
CGFloat iconH = 35;
CGFloat iconX = margin;
CGFloat iconY = margin;
_iconFrame = CGRectMake(iconX, iconY, iconW, iconH);
CGFloat nameX = CGRectGetMaxX(_iconFrame)+margin;
//依据Labele中文字的内容动态计算大小
//头文件NSAttributString
NSDictionary *attr = @{NSFontAttributeName:nameFont};
CGSize nameSize = [self sizeWithText:_weibo.name size:CGSizeMake(MAXFLOAT, MAXFLOAT) font:nameFont];
CGFloat nameW = nameSize.width;
CGFloat nameH = nameSize.height;
CGFloat nameY = iconY + (iconH - nameH)/2;
_nameFrame = CGRectMake(nameX, nameY, nameW, nameH);
CGFloat vipW = 10;
CGFloat vipH = 10;
CGFloat vipX = CGRectGetMaxX(_nameFrame)+margin;
CGFloat vipY = iconY +(iconH - vipH)/2;
_vipFrame = CGRectMake(vipX, vipY, vipW, vipH);
CGFloat textX = iconX;
CGFloat textY = CGRectGetMaxY(_iconFrame)+margin;
CGSize s = CGSizeMake([[UIScreen mainScreen] bounds].size.width - margin*2, MAXFLOAT);
CGSize textSize = [self sizeWithText:weibo.text size:s font:textFont];
_textFrame = CGRectMake(textX, textY, textSize.width, textSize.height);
CGFloat picW = 200;
CGFloat picH = 200;
CGFloat picX = iconX;
CGFloat picY = CGRectGetMaxY(_textFrame)+margin;
_pictureFrame = CGRectMake(picX, picY, picW, picH) ;
_rowHeight = 0;
if(self.weibo.picture){
_rowHeight = CGRectGetMaxY(_pictureFrame)+margin;
}else{
_rowHeight = CGRectGetMaxY(_textFrame)+margin;
}
}
///获取字符串的size
-(CGSize) sizeWithText:(NSString *) text size:(CGSize) size font:(UIFont *)font{
NSDictionary *dict = @{NSFontAttributeName:font };
CGSize sz = [text boundingRectWithSize:size options:NSStringDrawingUsesLineFragmentOrigin attributes:dict context:nil].size;
return sz;
}
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{
return ((CZWeiboFrame*)[self.weiboFrames objectAtIndex:indexPath.row]).rowHeight;<span style="font-family: Arial, Helvetica, sans-serif;"> </span>}