Move UIView up when the keyboard appears in iOS

2019-01-06 08:48发布

问题:

I have a UIView, it is not inside UIScrollView. I would like to move up my View when the keyboard appears. Before I tried to use this solution: How can I make a UITextField move up when the keyboard is present?.

It was working fine. But after inserting the data in the textfields, it takes me to another view, and when I get back to this page, its just jumping, and I couldn't see my text fields. Is there any better solution for this problem?

回答1:

Use the following code in order to show and hide the keyboard

//Declare a delegate, assign your textField to the delegate and then include these methods

-(BOOL)textFieldShouldBeginEditing:(UITextField *)textField {
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardDidShow:) name:UIKeyboardDidShowNotification object:nil];
    return YES;
}


- (BOOL)textFieldShouldEndEditing:(UITextField *)textField {
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardDidHide:) name:UIKeyboardDidHideNotification object:nil];

    [self.view endEditing:YES];
    return YES;
}


- (void)keyboardDidShow:(NSNotification *)notification
{
    // Assign new frame to your view 
    [self.view setFrame:CGRectMake(0,-110,320,460)]; //here taken -110 for example i.e. your view will be scrolled to -110. change its value according to your requirement.

}

-(void)keyboardDidHide:(NSNotification *)notification
{
    [self.view setFrame:CGRectMake(0,0,320,460)];
}


回答2:

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
}

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}

#pragma mark - keyboard movements
- (void)keyboardWillShow:(NSNotification *)notification
{
    CGSize keyboardSize = [[[notification userInfo] objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    [UIView animateWithDuration:0.3 animations:^{
        CGRect f = self.view.frame;
        f.origin.y = -keyboardSize.height;
        self.view.frame = f;
    }];
}

-(void)keyboardWillHide:(NSNotification *)notification
{
    [UIView animateWithDuration:0.3 animations:^{
        CGRect f = self.view.frame;
        f.origin.y = 0.0f;
        self.view.frame = f;
    }];
}


回答3:

I wrote a little category on UIView that manages temporarily scrolling things around without needing to wrap the whole thing into a UIScrollView. My use of the verb "scroll" here is perhaps not ideal, because it might make you think there's a scroll view involved, and there's not--we're just animating the position of a UIView (or UIView subclass).

There are a bunch of magic numbers embedded in this that are appropriate to my form and layout that might not be appropriate to yours, so I encourage tweaking this to fit your specific needs.

UIView+FormScroll.h:

#import <Foundation/Foundation.h>

@interface UIView (FormScroll) 

-(void)scrollToY:(float)y;
-(void)scrollToView:(UIView *)view;
-(void)scrollElement:(UIView *)view toPoint:(float)y;

@end

UIView+FormScroll.m:

#import "UIView+FormScroll.h"


@implementation UIView (FormScroll)


-(void)scrollToY:(float)y
{

    [UIView beginAnimations:@"registerScroll" context:NULL];
    [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
    [UIView setAnimationDuration:0.4];
    self.transform = CGAffineTransformMakeTranslation(0, y);
    [UIView commitAnimations];

}

-(void)scrollToView:(UIView *)view
{
    CGRect theFrame = view.frame;
    float y = theFrame.origin.y - 15;
    y -= (y/1.7);
    [self scrollToY:-y];
}


-(void)scrollElement:(UIView *)view toPoint:(float)y
{
    CGRect theFrame = view.frame;
    float orig_y = theFrame.origin.y;
    float diff = y - orig_y;
    if (diff < 0) {
        [self scrollToY:diff];
    }
    else {
        [self scrollToY:0];
    }

}

@end

Import that into your UIViewController, and then you can do

- (void)textFieldDidBeginEditing:(UITextField *)textField
{
    [self.view scrollToView:textField];
}

-(void) textFieldDidEndEditing:(UITextField *)textField
{
    [self.view scrollToY:0];
    [textField resignFirstResponder];
}

...or whatever. That category gives you three pretty good ways to adjust the position of a view.



回答4:

Bind a view to keyboard is also an option (see GIF at the bottom of the answer)

Swift 4

Use an extension: (Wasn't fully tested)

extension UIView{
    func bindToKeyboard(){
        NotificationCenter.default.addObserver(self, selector: #selector(UIView.keyboardWillChange(notification:)), name: Notification.Name.UIKeyboardWillChangeFrame, object: nil)
    }

    func unbindToKeyboard(){
        NotificationCenter.default.removeObserver(self, name: Notification.Name.UIKeyboardWillChangeFrame, object: nil)
    }
    @objc
    func keyboardWillChange(notification: Notification) {
        let duration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double
        let curve = notification.userInfo![UIKeyboardAnimationCurveUserInfoKey] as! UInt
        let curFrame = (notification.userInfo![UIKeyboardFrameBeginUserInfoKey] as! NSValue).cgRectValue
        let targetFrame = (notification.userInfo![UIKeyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
        let deltaY = targetFrame.origin.y - curFrame.origin.y

        UIView.animateKeyframes(withDuration: duration, delay: 0.0, options: UIViewKeyframeAnimationOptions(rawValue: curve), animations: {
            self.frame.origin.y+=deltaY

        },completion: nil)

    }
}

Swift 2 + 3

Use an extension:

extension UIView{
    func bindToKeyboard(){
        NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(UIView.keyboardWillChange(_:)), name: UIKeyboardWillChangeFrameNotification, object: nil)
    }


    func keyboardWillChange(notification: NSNotification) {

        let duration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double
        let curve = notification.userInfo![UIKeyboardAnimationCurveUserInfoKey] as! UInt
        let curFrame = (notification.userInfo![UIKeyboardFrameBeginUserInfoKey] as! NSValue).CGRectValue()
        let targetFrame = (notification.userInfo![UIKeyboardFrameEndUserInfoKey] as! NSValue).CGRectValue()
        let deltaY = targetFrame.origin.y - curFrame.origin.y


        UIView.animateKeyframesWithDuration(duration, delay: 0.0, options: UIViewKeyframeAnimationOptions(rawValue: curve), animations: {
                self.frame.origin.y+=deltaY

        },completion: nil)

    }  
}

Usage:

// view did load...
textField.bindToKeyboard()

...

// view unload
textField.unbindToKeyboard()

result:

important
Don't forget to remove the observer when view is unloading



回答5:

I found theDuncs answer very useful and below you can find my own (refactored) version:


Main Changes

  1. Now getting the keyboard size dynamically, rather than hard coding values
  2. Extracted the UIView Animation out into it's own method to prevent duplicate code
  3. Allowed duration to be passed into the method, rather than being hard coded

- (void)viewWillAppear:(BOOL)animated {
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
}

- (void)viewWillDisappear:(BOOL)animated {
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}

- (void)keyboardWillShow:(NSNotification *)notification {
    CGSize keyboardSize = [[[notification userInfo] objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    float newVerticalPosition = -keyboardSize.height;

    [self moveFrameToVerticalPosition:newVerticalPosition forDuration:0.3f];
}


- (void)keyboardWillHide:(NSNotification *)notification {
    [self moveFrameToVerticalPosition:0.0f forDuration:0.3f];
}


- (void)moveFrameToVerticalPosition:(float)position forDuration:(float)duration {
    CGRect frame = self.view.frame;
    frame.origin.y = position;

    [UIView animateWithDuration:duration animations:^{
        self.view.frame = frame;
    }];
}


回答6:

Based on Daniel Krom's solution. This is version in swift 3.0. Works great with AutoLayout, and moves whole view when keyboard appears.

extension UIView {

    func bindToKeyboard(){
        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillChange), name: NSNotification.Name.UIKeyboardWillChangeFrame, object: nil)
    }

    func unbindFromKeyboard(){
        NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillChangeFrame, object: nil)
    }

    @objc
    func keyboardWillChange(notification: NSNotification) {

        guard let userInfo = notification.userInfo else { return }

        let duration = userInfo[UIKeyboardAnimationDurationUserInfoKey] as! Double
        let curve = userInfo[UIKeyboardAnimationCurveUserInfoKey] as! UInt
        let curFrame = (userInfo[UIKeyboardFrameBeginUserInfoKey] as! NSValue).cgRectValue
        let targetFrame = (userInfo[UIKeyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
        let deltaY = targetFrame.origin.y - curFrame.origin.y

        UIView.animateKeyframes(withDuration: duration, delay: 0.0, options: UIViewKeyframeAnimationOptions(rawValue: curve), animations: {
            self.frame.origin.y += deltaY
        })
    }  
}

How to use it: Add bindToKeyboard function in viewDidLoad like:

override func viewDidLoad() {
    super.viewDidLoad()

    view.bindToKeyboard()
}

And add unbindFromKeyboard function in deinit:

deinit {
    view.unbindFromKeyboard()
}


回答7:

For all the issue related to KeyBoard just use IQKeyBoardManager it's helpful. https://github.com/hackiftekhar/IQKeyboardManager.



回答8:

try this one:-

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


[[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector (keyboardDidHide:)
                                                 name: UIKeyboardDidHideNotification object:nil];

-(void) keyboardDidShow: (NSNotification *)notif
    {
        CGSize keyboardSize = [[[notif userInfo] objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
        UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, keyboardSize.height+[self getTableView].tableFooterView.frame.size.height, 0.0);

        [self getTableView].contentInset = contentInsets;
        [self getTableView].scrollIndicatorInsets = contentInsets;

        CGRect rect = self.frame; rect.size.height -= keyboardSize.height;
        if (!CGRectContainsPoint(rect, self.frame.origin))
        {
            CGPoint scrollPoint = CGPointMake(0.0, self.frame.origin.y - (keyboardSize.height - self.frame.size.height));
            [[self getTableView] setContentOffset:scrollPoint animated:YES];
        }
    }

-(void) keyboardDidHide: (NSNotification *)notif
{
    UIEdgeInsets contentInsets = UIEdgeInsetsZero;
    [self getTableView].contentInset = contentInsets;
    [self getTableView].scrollIndicatorInsets = contentInsets;
}


回答9:

Based on theDunc's answer but written in Swift with Autolayout.

@IBOutlet weak var bottomConstraint: NSLayoutConstraint! // connect the bottom of the view you want to move to the bottom layout guide

override func viewWillAppear(animated: Bool) {
    super.viewWillAppear(animated)
    NSNotificationCenter.defaultCenter().addObserver(self,
                                                     selector: #selector(ConversationViewController.keyboardWillShow(_:)),
                                                     name: UIKeyboardWillShowNotification,
                                                     object: nil)

    NSNotificationCenter.defaultCenter().addObserver(self,
                                                     selector: #selector(ConversationViewController.keyboardWillHide(_:)),
                                                     name: UIKeyboardWillHideNotification,
                                                     object: nil)
}

override func viewWillDisappear(animated: Bool) {
    NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillShowNotification, object: nil)
    NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
    super.viewWillDisappear(animated)
}

// MARK: - Keyboard events

func keyboardWillShow(notification: NSNotification) {
    if let userInfo = notification.userInfo,
        keyboardFrame = userInfo[UIKeyboardFrameBeginUserInfoKey]
    {
        let keyboardSize = keyboardFrame.CGRectValue().size
        self.bottomConstraint.constant = keyboardSize.height
        UIView.animateWithDuration(0.3) {
            self.view.layoutIfNeeded()
        }
    }
}

func keyboardWillHide(notification: NSNotification) {
    self.bottomConstraint.constant = 0
    UIView.animateWithDuration(0.3) {
        self.view.layoutIfNeeded()
    }
}


回答10:

I have implemented a custom controller that dynamically calculates the size of the keyboard, scrolling textFields when it appears and disappears, even during rotation of the device. Works with all iOS devices. Just simply inherit the controller to have what you need. You can find it with all the instructions at the following link: https://github.com/mikthebig/ios-textfield-scroll



回答11:

Simple solution without adding observer notification

-(void)setViewMovedUp:(BOOL)movedUp
{
    [UIView beginAnimations:nil context:NULL];

    [UIView setAnimationDuration:0.3]; // if you want to slide up the view

    CGRect rect = self.view.frame;

    if (movedUp)
    {
        // 1. move the view's origin up so that the text field that will be hidden come above the keyboard
        // 2. increase the size of the view so that the area behind the keyboard is covered up.
        rect.origin.y -= kOFFSET_FOR_KEYBOARD;
        rect.size.height += kOFFSET_FOR_KEYBOARD;
    }
    else
    {
        // revert back to the normal state.
        rect.origin.y += kOFFSET_FOR_KEYBOARD;
        rect.size.height -= kOFFSET_FOR_KEYBOARD;
    }
    self.view.frame = rect;

    [UIView commitAnimations];
}


-(void)textFieldDidEndEditing:(UITextField *)sender
{
     if  (self.view.frame.origin.y >= 0)
        {
            [self setViewMovedUp:NO];
        }
}

-(void)textFieldDidBeginEditing:(UITextField *)sender
{
        //move the main view, so that the keyboard does not hide it.
        if  (self.view.frame.origin.y >= 0)
        {
            [self setViewMovedUp:YES];
        }
}

Where

#define kOFFSET_FOR_KEYBOARD 80.0


回答12:

Swift 4

NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillChange), name: .UIKeyboardWillChangeFrame, object: nil)

@objc func keyboardWillChange(notification: NSNotification) {

        let duration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double
        let curve = notification.userInfo![UIKeyboardAnimationCurveUserInfoKey] as! UInt
        let curFrame = (notification.userInfo![UIKeyboardFrameBeginUserInfoKey] as! NSValue).cgRectValue
        let targetFrame = (notification.userInfo![UIKeyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
        let deltaY = targetFrame.origin.y - curFrame.origin.y

        UIView.animateKeyframes(withDuration: duration, delay: 0.0, options: UIViewKeyframeAnimationOptions(rawValue: curve), animations: {
            self.YourView.frame.origin.y+=deltaY
        },completion: nil)
    }


回答13:

Just in case someone is looking for solution in Swift, throw this in your code:

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)

    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow(notification:)), name: .UIKeyboardWillShow, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide(notification:)), name: .UIKeyboardWillHide, object: nil)
}

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)

    NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillShow, object: nil)
    NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillHide, object: nil)
}


@objc func keyboardWillShow(notification: Notification) {
    if let userInfo = notification.userInfo {
        if let keyboardSize = (userInfo[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
            UIView.animate(withDuration: 0.3) {
                var alteredFrame = self.view.frame
                alteredFrame.origin.y = -keyboardSize.height
                self.view.frame = alteredFrame
            }
        }
    }
}

@objc func keyboardWillHide(notification: Notification) {
    UIView.animate(withDuration: 0.3) {
        var alteredFrame = self.view.frame
        alteredFrame.origin.y = 0.0
        self.view.frame = alteredFrame
    }
}


回答14:

Here you go. I have used this code with UIView, though. You should be able to make those adjustments for scrollview.

    func addKeyboardNotifications() {
        NotificationCenter.default.addObserver(self,
                                               selector: #selector(keyboardWillShow(notification:)),
                                               name: NSNotification.Name.UIKeyboardWillShow, object: nil)
        NotificationCenter.default.addObserver(self,
                                               selector: #selector(keyboardWillHide(notification:)),
                                               name: NSNotification.Name.UIKeyboardWillHide, object: nil)
    }

    func keyboardWillShow(notification: NSNotification) {

        if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
            let duration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double
// if using constraints            
// bottomViewBottomSpaceConstraint.constant = keyboardSize.height
self.view.frame.origin.y -= keyboardSize.height
            UIView.animate(withDuration: duration) {
                self.view.layoutIfNeeded()
            }
        }
    }
    func keyboardWillHide(notification: NSNotification) {

        let duration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double
//if using constraint
//        bottomViewBottomSpaceConstraint.constant = 0
self.view.frame.origin.y = 0
        UIView.animate(withDuration: duration) {
            self.view.layoutIfNeeded()
        }
    }

Don't forget to remove notifications at right place.

func removeKeyboardNotifications() {
    NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillShow, object: nil)
    NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}


回答15:

i just created a lightweight keyboard handler to follow keyboard frame.

Usage:

 self.keyboardHandler = [EDKeyboardHandler new];

  [self.keyboardHandler listenWithBlock:^(KeyboardInfo *model)
  {
    //adjust view positions according to keyboard position here
  }];

and the KeyboardInfo model has the following properties:

typedef enum : NSUInteger {
    KeyboardStatusDidShow,
    KeyboardStatusWillShow,
    KeyboardStatusDidHide,
    KeyboardStatusWillHide,
} KeyboardStatus;

@interface KeyboardInfo:NSObject

@property (nonatomic,readonly) NSTimeInterval animationDuration;
@property (nonatomic,readonly) CGRect keyboardFrame;
@property (nonatomic,readonly) NSInteger animationCurve;
@property (nonatomic,readonly) KeyboardStatus status;

@end

check GitHub project for details and cocoaPods integration.



回答16:

Declare a delegate, assign your text field to the delegate and then include these methods.

Assuming you have a login form with email and password text fields, this code will fit perfectly:

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {

    [self.emailTextField resignFirstResponder];
    [self.passwordTextField resignFirstResponder];

}

- (BOOL)textFieldShouldReturn:(UITextField *)textField {

    if (self.emailTextField == textField) {
        [self.passwordTextField becomeFirstResponder];
    } else {
        [self.emailTextField resignFirstResponder];
        [self.passwordTextField resignFirstResponder];
    }
    return NO;
}
- (void)viewWillAppear:(BOOL)animated {
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
}

- (void)viewWillDisappear:(BOOL)animated {
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}

#pragma mark - keyboard movements
- (void)keyboardWillShow:(NSNotification *)notification
{
    CGSize keyboardSize = [[[notification userInfo] objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    [UIView animateWithDuration:0.3 animations:^{
        CGRect f = self.view.frame;
        f.origin.y = -0.5f * keyboardSize.height;
        self.view.frame = f;
    }];
}

-(void)keyboardWillHide:(NSNotification *)notification
{
    [UIView animateWithDuration:0.3 animations:^{
        CGRect f = self.view.frame;
        f.origin.y = 0.0f;
        self.view.frame = f;
    }];
}


回答17:

It can be done easily & automatically if that textfield is in a table's cell (even when the table.scrollable = NO).

NOTE that: the position and size of the table must be reasonable. e.g:

  • if the y position of table is 100 counted from the view's bottom, then the 300 height keyboard will overlap the whole table.
  • if table's height = 10, and the textfield in it must be scrolled up 100 when keyboard appears in order to be visible, then that textfield will be out of the table's bound.