Disabling automatic scrolling of UITableView when

Question

I'm using custom UITableViewCells inside my UITableView. Each of these UITableViewCells is pretty high and contains a UITextField at the top.

When a user taps the UITextField in order to edit it, a keyboard appears and the UITableView scrolls automatically so that the cell is at the top of the screen.

The problem is that this scrolls the UITableView to the bottom of the UITableViewCell, not the top. When the UITableViewCell is high and edited the UITextField is at the top so you can't see the UITextField. I know how to scroll the UITableView programmatically, but I just don't know how to disable this automatic scrolling so that I can scroll the UITableView on my own. How can I do this?

Answer 1

Define properties for your UITableViewController:

@property (nonatomic) BOOL scrollDisabled;
@property (nonatomic) CGFloat lastContentOffsetY;

Before you call becomeFirstResponder:

// Save the table view's y content offset 
lastContentOffsetY = tableViewController.tableView.contentOffset.y;
// Enable scrollDisabled
scrollDisabled = YES;

Add the following code to your table view controller:

-(void)scrollViewDidScroll:(UIScrollView *)scrollView
{
    if (self.scrollDisabled) {
        [self.tableView setContentOffset:CGPointMake(0, lastContentOffsetY)];
    }
    ...
}

After you call resignFirstResponder, set scrollDisabled = NO.

Answer 2

You can do the following:

- (void)registerForKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillShow:)
                                                 name:UIKeyboardWillShowNotification object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardDidShow:)
                                                 name:UIKeyboardDidShowNotification object:nil];
}

- (void)unregisterForKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardDidShowNotification object:nil];
}

- (void)keyboardWillShow:(NSNotification *)notification
{
    self.tableView.scrollEnabled = NO;
}

- (void)keyboardDidShow:(NSNotification *)notification
{
    double delayInSeconds = 0.3;
    dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
    dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
            self.tableView.scrollEnabled = YES;
    });
}

Then implement this UIScrollViewDelegate method

- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
    if (! self.tableView.scrollEnabled)
        [self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForItem:0 inSection:0] atScrollPosition:UITableViewScrollPositionTop animated:NO];
}

!!! But be warned, that if the user taps in a location in the UITextField that will be covered by the Keyboard, then it won't scroll.

From my point of view, the best thing to do is to make sure that all the cells from top to then one with the UITextField included, will be visible when then Keyboard will show.