is this a valid workaround to keyboard obscuring content - ios

Question

I have a Tableview where the user can enter values into a textField as one of the custom cells
Apple have some documentation about how to adjust view content by repositioning the view clear of the keyboard's vertical dimension ( Here ) but it relies upon one placing that view into a UIScrollView. I cant do this with a tableview.
I could redesign the app so that the entry gets done in a separate detail view using the usual navigation controller, but i'd rather the user not have to perform an extra touch ( and be ferried off into yet another screen ) if possible. I like the idea of doing the deed "right where we are"
so my workaround to have a few extra tableview cells at the bottom containing a %20 or so, normal usage shouldn't register the oddity, as they are only focussed on what is visible.
I'd have to store the spaces in my datasource array and then sort descending, but that's OK
the question is, is this good practice? and even more possibly, could it be against Apple's HIG sufficient for refusal?

Answer 1

UITableView is a subclass of UIScrollView, so should be able to adjust the content and scroll view insets just like in the example you linked.

Answer 2

The way I've solved this issue is to subclass UITableView. Here's what I've done:
// AOTableView.h file
typedef enum
{
AOKeyboardStateUnknown = 0,
AOKeyboardStateShowing,
AOKeyboardStateHidden
} AOKeyboardState;
#import <UIKit/UIKit.h>
#import "AOKeyboardState.h"
#interface AOTableView : UITableView
#property (nonatomic) BOOL observeKeyboardNotifications;
#property (nonatomic) AOKeyboardState keyboardState;
#end
// AOTableView.m file
#import "AOTableView.h"
#interface AOTableView(Private)
#property (nonatomic) CGRect frame0;
- (void)setup;
- (void)keyboardWillShow:(NSNotification *)notification;
- (void)keyboardWillHide:(NSNotification *)notification;
#end
#implementation AOTableView
#pragma mark - Object lifecycle
- (void)awakeFromNib
{
[self setup];
}
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self)
{
[self setup];
}
return self;
}
- (void)setup
{
self.contentSize = self.frame.size;
self.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
_keyboardState = AOKeyboardStateUnknown;
_frame0 = self.frame;
_observeKeyboardNotifications = NO;
}
- (void)dealloc
{
[[NSNotificationCenter defaultCenter] removeObserver:self];
}
#pragma mark - Custom setters
- (void)setObserveKeyboardNotifications:(BOOL)observeKeyboardNotifications
{
if (_observeKeyboardNotifications == observeKeyboardNotifications)
return;
_observeKeyboardNotifications = observeKeyboardNotifications;
if (_observeKeyboardNotifications)
{
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
}
else
{
[[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
[[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}
}
#pragma mark - UIKeyboard Notifications
- (void)keyboardWillShow:(NSNotification *)notification
{
if (self.keyboardState == AOKeyboardStateShowing)
return;
self.frame0 = self.frame;
self.keyboardState = AOKeyboardStateShowing;
NSDictionary* info = [notification userInfo];
CGRect keyboardFrame = CGRectZero;
[[info objectForKey:UIKeyboardFrameEndUserInfoKey] getValue:&keyboardFrame];
CGRect frame = self.frame0;
frame.size.height = CGRectGetMinY(keyboardFrame) - CGRectGetMinY(frame);
self.frame = frame;
[self scrollToRowAtIndexPath:self.indexPathForSelectedRow atScrollPosition:UITableViewScrollPositionMiddle animated:YES];
[self deselectRowAtIndexPath:self.indexPathForSelectedRow animated:NO];
}
- (void)keyboardWillHide:(NSNotification *)notification
{
if (self.keyboardState == AOKeyboardStateHidden)
return;
self.keyboardState = AOKeyboardStateHidden;
self.frame = self.frame0;
}
#end
After creation (or loading the view from an IBOutlet), you call this method to tell the class to start listening for keyboard notifications:
[tableViewInstance setObserveKeyboardNotifications:YES];
Whenever a user clicks on a cell, it becomes the self.indexPathForSelectedRow cell... so its scrolled to by the AOTableView instance automatically.
For this to work, though, I've had to turn off userInteraction on the UITextField within the cell (otherwise, the device can get confused about if the user is clicking on the cell or on the text field). Instead, when a user selects a cell that has a text field, I tell the text field to the become first responder, like this:
[cell.textField becomeFirstResponder];
I hope this helps.

Answer 3

You don't need the extra cells or anything fancy.
Since your text fields are inside the table view cells, you can use the following:
- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField
{
UITableViewCell *cell = (UITableViewCell *)textField.superview.superview;
NSIndexPath *indexPath = [self.tableView indexPathForCell:cell];
[self.tableView scrollToRowAtIndexPath:indexPath atScrollPosition:UITableViewScrollPositionMiddle animated:YES];
return YES;
}
This means that the keyboard will scroll appropriately each time a text field becomes first responder. This takes advantage of the table view being a scroll view subclass.
Note that this assumes:
Your (table) view controller is the text fields' delegate.
Your text field is a subview of the cell's content view, not the cell itself.
If the text field is a subview of the cell, the first line of the method above should reference only one superview (i.e., textField.superview).