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copied!<p>What you really want to do is observe the UIKeyboard(Did|Will)(Show|Hide) notifications. They contain in their userInfo dictionaries the beginning and ending frame, as well as the correct animation curve and durations.</p> <p>So after observing this notification, when it's posted move your text field based on the size of the frame passed in the notification, according to the animation hints provided.</p> <p>You can see more information in the UIWindow class reference's "notifications" section: <a href="https://developer.apple.com/library/ios/#documentation/uikit/reference/UIWindow_Class/UIWindowClassReference/UIWindowClassReference.html" rel="noreferrer">https://developer.apple.com/library/ios/#documentation/uikit/reference/UIWindow_Class/UIWindowClassReference/UIWindowClassReference.html</a></p> <p>Below is a sample view controller implementation. The nib for this view controller was just a single text field, with an outlet connected to it, and the text field's delegate set to the view controller.</p> <pre><code>@interface ViewController () - (void)viewControllerInit; @end @implementation ViewController @synthesize textField; - (id)initWithCoder:(NSCoder *)coder { self = [super initWithCoder:coder]; if (self) { [self viewControllerInit]; } return self; } - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { if (self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]) { [self viewControllerInit]; } return self; } - (void)viewControllerInit { [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil]; [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil]; } - (void)dealloc { [[NSNotificationCenter defaultCenter] removeObserver:self]; } #pragma mark - Notification Handlers - (void)keyboardWillShow:(NSNotification *)notification { // I'll try to make my text field 20 pixels above the top of the keyboard // To do this first we need to find out where the keyboard will be. NSValue *keyboardEndFrameValue = [[notification userInfo] objectForKey:UIKeyboardFrameEndUserInfoKey]; CGRect keyboardEndFrame = [keyboardEndFrameValue CGRectValue]; // When we move the textField up, we want to match the animation duration and curve that // the keyboard displays. So we get those values out now NSNumber *animationDurationNumber = [[notification userInfo] objectForKey:UIKeyboardAnimationDurationUserInfoKey]; NSTimeInterval animationDuration = [animationDurationNumber doubleValue]; NSNumber *animationCurveNumber = [[notification userInfo] objectForKey:UIKeyboardAnimationCurveUserInfoKey]; UIViewAnimationCurve animationCurve = [animationCurveNumber intValue]; // UIView's block-based animation methods anticipate not a UIVieAnimationCurve but a UIViewAnimationOptions. // We shift it according to the docs to get this curve. UIViewAnimationOptions animationOptions = animationCurve << 16; // Now we set up our animation block. [UIView animateWithDuration:animationDuration delay:0.0 options:animationOptions animations:^{ // Now we just animate the text field up an amount according to the keyboard's height, // as we mentioned above. CGRect textFieldFrame = self.textField.frame; textFieldFrame.origin.y = keyboardEndFrame.origin.y - textFieldFrame.size.height - 40; //I don't think the keyboard takes into account the status bar self.textField.frame = textFieldFrame; } completion:^(BOOL finished) {}]; } - (void)keyboardWillHide:(NSNotification *)notification { NSNumber *animationDurationNumber = [[notification userInfo] objectForKey:UIKeyboardAnimationDurationUserInfoKey]; NSTimeInterval animationDuration = [animationDurationNumber doubleValue]; NSNumber *animationCurveNumber = [[notification userInfo] objectForKey:UIKeyboardAnimationCurveUserInfoKey]; UIViewAnimationCurve animationCurve = [animationCurveNumber intValue]; UIViewAnimationOptions animationOptions = animationCurve << 16; [UIView animateWithDuration:animationDuration delay:0.0 options:animationOptions animations:^{ self.textField.frame = CGRectMake(20, 409, 280, 31); //just some hard coded value } completion:^(BOOL finished) {}]; } #pragma mark - View lifecycle - (void)viewDidUnload { [self setTextField:nil]; [super viewDidUnload]; // Release any retained subviews of the main view. // e.g. self.myOutlet = nil; } #pragma mark - UITextFieldDelegate - (BOOL)textFieldShouldReturn:(UITextField *)textField { [self.textField resignFirstResponder]; return YES; } @end </code></pre>

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