How to dynamically set the height of a UITableView?

Question

I have a tableview with different cell heights using the heightForRowAtIndexPath: method.

I would like to dynamically set the height of a UITableView. At the moment I'm setting the dimensions of the tableView in viewDidLoad method using:

self.tableView = [[UITableView alloc] initWithFrame:CGRectMake(10, 770, 310, 400)];
self.tableView.dataSource = self;
self.tableView.delegate = self;

I thought maybe I could add this: self.tableView.contentSize.height; but the problem of course is that the content size is only calculated after the table loads, so if I put it in

self.tableView = [[UITableView alloc] initWithFrame:CGRectMake(10, 770, 310, self.tableView.contentSize.height)];

it doesn't work.

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    NSString *description = [photosFromCommentsArray objectAtIndex:indexPath.row];
    //   NSLog(@"description is %@",description);

    if(description == (id)[NSNull null])
    {
        return 70; 
    }
    else
    {
        return 200;
    }
}

Answer 1

Add an observer for the contentSize property on the table view, and adjust the frame accordingly

[self.tableView addObserver:self forKeyPath:@"contentSize" options:0 context:NULL];

then in the callback:

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context
{
    CGRect frame = self.tableView.frame;
    frame.size = self.tableView.contentSize;
    self.tableView.frame = frame;
}