IOS 动态改变cell的高度

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {

static NSString *CellIdentifier = @"Cell";

UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] ;
UILabel *label = [[UILabel alloc] initWithFrame:CGRectZero];
label.tag = 1;
label.lineBreakMode=NSLineBreakByCharWrapping;
label.highlightedTextColor = [UIColor whiteColor];
label.numberOfLines = 0;
label.opaque = NO; // 选中Opaque表示视图后面的任何内容都不应该绘制
label.backgroundColor = [UIColor clearColor];
[cell.contentView addSubview:label];

}

UILabel *label = (UILabel *)[cell viewWithTag:1];
NSString *text = [_dataList objectAtIndex:indexPath.row];;
CGRect cellFrame = [cell frame];
cellFrame.origin = CGPointMake(0, 0);
CGRect rect = CGRectInset(cellFrame, 2, 2);
label.frame = rect;

[label sizeToFit];

label.text =[_dataList objectAtIndex:indexPath.row];

if (label.frame.size.height > 46) {
cellFrame.size.height = 50 + label.frame.size.height - 46;
}
else {
cellFrame.size.height = 50;
}
[cell setFrame:cellFrame];

return cell;
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [self tableView:tableView cellForRowAtIndexPath:indexPath];
return cell.frame.size.height;
}