UISegementedControl reverts back to original frame after touch

Question

Every time I click on my UISegementedControl it snaps back to its original frame. I can see it barely through my translucent toolbar. I have a UIViewController with a UITableView, and UIToolBar like this:

There is a UISegmentedControl hidden just below the table view, behind the toolbar:

The Filter button calls the 'onFilterButtonPressed' method

- (IBAction)onFilterButtonPressed:(id)sender
{
    if(self.filterBar.hidden){
        [self showFilterBar];
    } else {
        [self hideFilterBar];
    }
}

- (void)hideFilterBar
{
    CGRect filterBarFrame = CGRectMake(0, self.view.frame.size.height+(self.filterBar.frame.size.height+1), self.filterBar.frame.size.width, self.filterBar.frame.size.height);
    CGRect tableViewFrame = CGRectMake(self.tableView.frame.origin.x, self.tableView.frame.origin.y,self.tableView.frame.size.width, self.tableView.frame.size.height+(self.filterBar.frame.size.height+1));

    [UIView animateWithDuration:0.3 animations:^{
        [self.filterBar setFrame:filterBarFrame];
        [self.tableView setFrame:tableViewFrame];
    } completion:^(BOOL finished) {
        self.filterBar.hidden = YES;
    }];
}

- (void)showFilterBar
{
    CGRect filterBarFrame = CGRectMake(0, self.view.frame.size.height-(self.filterBar.frame.size.height+1), self.filterBar.frame.size.width, self.filterBar.frame.size.height);
    CGRect tableViewFrame = CGRectMake(self.tableView.frame.origin.x, self.tableView.frame.origin.y,self.tableView.frame.size.width, self.tableView.frame.size.height-(self.filterBar.frame.size.height+1));

    self.filterBar.hidden = NO;
    [UIView animateWithDuration:0.3 animations:^{
        [self.tableView setFrame:tableViewFrame];
        [self.filterBar setFrame:filterBarFrame];
    }];

}

Answer 1

This is because of auto layout. With that turned on (which it is by default), you should do any positioning or resizing of views by modifying constraints, not setting frames.