UITableView with Keyboard handling for UITextFields

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UITableView has its parent class as UIScrollView. So, if you have a UITableViewCell , which has UITextField, then it needs to handle the contentOffset.

More details on contentOffset (another url)and keyboard handling  in iOS.

Lets say if we want to add a bottom inset of 216 (approx. kyeboard height). the following would be the code
You basically change the content Offset while the content size remains the same.

self.contentOffset = UIEdgeInset(0,0,216,0).

This will move the content ( in the UITableView) up by 216.

The below code also handles autosuggestion bar ,  as the autosuggestion delta (approx. 29) gets added to existing delta. And Removes it accordingly.


-(void)viewWillAppear:(BOOL)animated{
    [super viewWillAppear:animated];
    [self registerNotifications:YES];
}

-(void)viewWillDisappear:(BOOL)animated{
    [super viewWillDisappear:animated];
    [self registerNotifications:NO];
}

-(void)registerNotifications:(BOOL)registerNotifications{
    if(registerBoardNotifications){
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(willShowKeyboard:) name:UIKeyboardWillShowNotification object:nil];
        
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(willHideKeyboard:) name:UIKeyboardWillHideNotification object:nil];
    }else{
        [[NSNotificationCenter  defaultCenter] removeObserver:self];
    }
    
}

-(void)willShowKeyboard:(NSNotification*) notification{
    // Retrieve the keyboard begin / end frame values
    CGRect beginFrame = [[notification.userInfo objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue];
    CGRect endFrame =  [[notification.userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
    CGFloat delta = (beginFrame.origin.y - endFrame.origin.y);
    
    if(delta==0){
        return; //Nothing has changed so skip
    }

    NSLog(@"Delta = %f",delta); // Keyboard height offset , Auto - suggestion height
    UIEdgeInsets contentInsets = self.tableView.contentInset ;
    contentInsets.bottom += delta;
    [self.tableView setContentInset:contentInsets];
    
    [self.tableView setScrollIndicatorInsets:contentInsets];
    
    
}

-(void)willHideKeyboard:(NSNotification*) notification{
    [self.tableView setContentInset:UIEdgeInsetsZero];
    [self.tableView setScrollIndicatorInsets:UIEdgeInsetsZero];

}



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