UIKeyboardWillChangeFrameNotification doesn't get fired while dictation (Speech to text) button pressed - ios

Question

I am developing an app with a chat functionality, so my requirement is to show the textfield on top of keyboard. As it was required to not use scroll view I have taken a textfield on a UIView and I am using keyborad notifications (UIKeyboardWillChangeFrameNotification and UIKeyboardWillHideNotification) to scroll textfield accordingly.
I am facing an issue for iPhone x device when "predictive text" is on and user press dictation button, there will be a gap between textfield and keyboard as dictation doesn't need "predictive text".
I am trying to detect a keyboard height via UIKeyboardWillChangeFrameNotification but it doesn't get fire while dictation button get pressed.
Adding my sample code below.
#interface ViewController ()
#property (weak, nonatomic) IBOutlet NSLayoutConstraint *bottomConstraints;
#property (weak, nonatomic) IBOutlet UITextField *chatTextField;
#end
#implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(keyboardFrameChange:) name:UIKeyboardWillChangeFrameNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(keywindowResign:) name:UIKeyboardWillShowNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
// Do any additional setup after loading the view, typically from a nib.
}
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:YES];
}
- (void)keyboardFrameChange:(NSNotification *)notification
{
NSDictionary * userInfo = [notification userInfo];
CGRect keyboardRect = [userInfo[UIKeyboardFrameEndUserInfoKey] CGRectValue];
double duration = [userInfo[UIKeyboardAnimationDurationUserInfoKey] doubleValue];
// Anchor the bottom of the message view to the top of the keyboard.
[UIView animateWithDuration:duration animations:^{
self.bottomConstraints.constant = 0 - CGRectGetHeight(keyboardRect) + self.view.safeAreaInsets.bottom;
[self.view layoutIfNeeded];
}];
}
- (void)keyboardWillHide:(NSNotification *)notification
{
NSDictionary * userInfo = [notification userInfo];
double duration = [userInfo[UIKeyboardAnimationDurationUserInfoKey] doubleValue];
// Anchor the bottom of the message view to the bottom of the screen.
[UIView animateWithDuration:duration animations:^{
self.bottomConstraints.constant = 0;
[self.view layoutIfNeeded];
}];
}
- (void)keywindowResign:(NSNotification *)notification
{
NSLog(#"%s","Key window resign");
}
- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
[self.view endEditing:true];
}
- (void)dealloc {
[[NSNotificationCenter defaultCenter] removeObserver:self];
}
Please check screenshots to understand it more.

Answer 1

I just created a quick test project and it seems like the notification is coming through fine on my end when hitting the dictation button. I can only speculate as to what could be going awry for you since you didn't include any of your code at all, but a couple of guesses are:
The notification is coming through, but the calculations adjusting for the keyboard height aren't correct (perhaps not taking into account the safeAreaInsets.bottom?)
You're removing yourself as an observer of the keyboard notifications at some point before the notification for the keyboard frame change for dictation comes through.
Here's my sample code that worked for me:
#import "ViewController.h"
#interface ViewController ()
#property (strong, nullable) IBOutlet UITextField *tf;
#property (strong, nullable) IBOutlet UIView *redView;
#property (strong, nullable) IBOutlet NSLayoutConstraint *redViewBottomConstraint;
- (IBAction)resignActiveOnTF:(id)sender;
- (void)keyboardWillChangeFrame:(NSNotification *)notification;
- (void)keyboardWillHide:(NSNotification *)notification;
#end
#implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(keyboardWillChangeFrame:) name:UIKeyboardWillChangeFrameNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
}
- (void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
// put the redView off the bottom of the screen initially (include safe area insets on the bottom
self.redViewBottomConstraint.constant = -(self.redView.frame.size.height + self.view.safeAreaInsets.bottom);
}
- (void)keyboardWillChangeFrame:(NSNotification *)notification {
[[NSOperationQueue mainQueue] addOperationWithBlock:^{
CGFloat keyboardHeight = [[[notification userInfo] objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size.height;
[self.view layoutIfNeeded];
// adjust the constraint by the keyboard height and account for the safe area insets on the bottom as well
self.redViewBottomConstraint.constant = keyboardHeight - self.view.safeAreaInsets.bottom;
[UIView animateWithDuration:0.4f animations:^{
self.redView.alpha = 1.0f;
[self.view layoutIfNeeded];
}];
}];
}
- (void)keyboardWillHide:(NSNotification *)notification {
[[NSOperationQueue mainQueue] addOperationWithBlock:^{
[self.view layoutIfNeeded];
self.redViewBottomConstraint.constant = -(self.redView.frame.size.height + self.view.safeAreaInsets.bottom);
[UIView animateWithDuration:0.25f animations:^{
self.redView.alpha = 0.0f;
[self.view layoutIfNeeded];
}];
}];
}
- (IBAction)resignActiveOnTF:(id)sender {
[self.tf resignFirstResponder];
}
- (void)dealloc {
[[NSNotificationCenter defaultCenter] removeObserver:self];
}
#end
And an example of it an action on simulator:
If none of this is helpful for you, i'd highly recommend trying to reproduce this in a very simple example and post your code so others can help.
Edit:
I copied your sample code into a new view controller, and it seems to be working fine for me. I did make one minor modification on my end for the constraint constant calculation (my bottom constraint is the bottom of the view that's going over the keyboard down to the bottom of the safe area):
- (void)keyboardFrameChange:(NSNotification *)notification
{
NSDictionary * userInfo = [notification userInfo];
CGRect keyboardRect = [userInfo[UIKeyboardFrameEndUserInfoKey] CGRectValue];
double duration = [userInfo[UIKeyboardAnimationDurationUserInfoKey] doubleValue];
// Anchor the bottom of the message view to the top of the keyboard.
[UIView animateWithDuration:duration animations:^{
self.bottomConstraints.constant = (CGRectGetHeight(keyboardRect) - self.view.safeAreaInsets.bottom);
[self.view layoutIfNeeded];
}];
}
although I'm assuming yours is a different constraint in your xib?
I've tried running this directly on an iPhone 6s and it works there as well. I don't have an iPhone X physical device handy to test it on.