UITextView appearance delayed - uitextview

Question

I have a tableView, and a "Reload" button that fetches data from a URL and reloads the table, a costly operation (in particular the fetch part).
I want display info to the user while this is happening, so I thought I'd put up a "Loading" UITextView on top, do the fetch/reload operation, then remove the UITextView.
Here's the code:
- (IBAction)refreshData:(id)sender {
UITextView *textView = [[UITextView alloc] initWithFrame:CGRectMake(0, self.view.frame.size.height-30, self.view.frame.size.width, 30)];
[self.view addSubview:textView];
textView.text = #"Loading..";
textView.textColor = [UIColor whiteColor];
textView.backgroundColor = [UIColor grayColor];
textView.editable = NO;
[self fetchData];
[self.tableView reloadData];
[textView removeFromSuperview];
}
The behavior I get is that the fetchData executes before the UITextView renders on screen. I know this because I have NSLogs inside fetchData that execute before the UITextView shows up on screen.
Is there something obvious I'm missing here? Thanks.

Answer 1

Replace [self fetchData]; with
[self performSelectorInBackground:#selector(fetchData) withObject:nil];
Then inside your fetchData method, after your fetch is done, add
[self performSelectorOnMainThread:#selector(fetchDataFinished) withObject:nil waitUntilDone:NO];
where the new method fetchDataFinished is defined as
-(void) fetchDataFinished{
[self.tableView reloadData];
[self.textView removeFromSuperview];
}
Note that you have to make textView a property so it is accessible in this method.
I have not tried out the above for your particular case, but I have used similar constructs successfully in many similar situations.