confusing about the height of cell, UITableViewCell,iOS

I am loading a custom cell from xib in which the height of cell is 64 and then using heightForRowAtIndexPath to change the height of cell like following :

- (void)viewDidLoad
{
    [super viewDidLoad];
    CGRect frame    =   CGRectMake(0, 0, self.view.bounds.size.width, self.view.bounds.size.height);
    UITableView *tableView = [[UITableView alloc] initWithFrame:frame style:UITableViewStylePlain];
    tableView.delegate = self;
    tableView.dataSource = self;
    UINib *cellNIB                      =   [UINib nibWithNibName:NSStringFromClass([TableCell class]) bundle:nil];

    [tableView registerNib:cellNIB forCellReuseIdentifier:NSLocalizedString(@"TableCell", nil)];

    [self.view addSubview:tableView];
}

(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath { 
    return 400 ; 
}

At cellForRowAtIndex, I am printing out the height of cell

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    TableCell *cell     =   [tableView dequeueReusableCellWithIdentifier:NSLocalizedString(@"TableCell", nil)];
    NSLog(@"height at:%ld is %@",(long)indexPath.item,NSStringFromCGRect(cell.frame));
    [cell setGradient];

    return cell;
}

It is interesting that the console gives me the height of cell of 64 ( which comes from the xib )

Is it supposed to be 400 ?

Any ideas why I am getting 64 instead of 400. Any comments are welcomed here. Thanks