-(void)touchedButtonInCell:(id)sender
{
    // Obtain the current number string entered from the pinpad.
    _pinpadNumber = [_pinpadNumber stringByAppendingFormat:@"%i", [sender tag]];

    // Verification of values
    NSLog(@"%i", [sender tag]);
    NSLog(@"%@", _pinpadNumber);

    // Check the entry of the PINPAD_NUMBER_LENGTH character/number
    if ([_pinpadNumber length] >= PINPAD_NUMBER_LENGTH)
    {
        // Trigger delegate method to handle the pin pad number received.
        if ([_delegate respondsToSelector:@selector(receivedPinPadNumber:)])
        {
            [_delegate receivedPinPadNumber:_pinpadNumber];
        }
        // Reset the contents of the pin pad number string
        _pinpadNumber = @"";
    }

    // Ensure all elements are scrambled for next number entry.
    [self scramblePinpadGridView];
}

_pinpadNumber = [_pinpadNumber stringByAppendingFormat:@"%i", [sender tag]];