动态改变UITable单元格的高度？

你可以试试下面的例子：

 - (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath         *)indexPath {

NSDictionary *itemAtIndex = (NSDictionary *)[chatQuestions objectAtIndex:indexPath.row];

if ([self sizeForText:[itemAtIndex objectForKey:@"text"]].height+20>50) {
    return [self sizeForText:[itemAtIndex objectForKey:@"text"]].height+20;
}
else{
    return 50;}



}

 -(CGSize)sizeForText:(NSString*)text
  {


CGSize constraintSize;

constraintSize.width = 190.0f;

constraintSize.height = MAXFLOAT;
UIFont *labelFont = [UIFont fontWithName:@"Noteworthy-Light" size:18];

CGSize stringSize =[text sizeWithFont:labelFont constrainedToSize: constraintSize lineBreakMode: UILineBreakModeWordWrap];

return stringSize;
}