iOS 26 keyboard measurement and height fixes

Chatto/Source/ChatController/BaseChatViewController.swift

@@ -318,6 +318,21 @@ open class BaseChatViewController: UIViewController,
         self.keyboardTracker = KeyboardTracker(viewController: self, inputBarContainer: self.inputBarContainer, heightBlock: heightBlock, notificationCenter: self.notificationCenter)
 
         (self.view as? BaseChatViewControllerViewProtocol)?.bmaInputAccessoryView = self.keyboardTracker?.trackingView
+
+        if #available(iOS 26, *) {
+            notificationCenter.removeObserver(self.keyboardTracker!)
+            inputContainerBottomConstraint.isActive = false
+            inputBarContainer.translatesAutoresizingMaskIntoConstraints = false
+
+            NSLayoutConstraint.activate([
+                inputBarContainer.leadingAnchor.constraint(equalTo: view.leadingAnchor),
+                inputBarContainer.trailingAnchor.constraint(equalTo: view.trailingAnchor),
+                inputBarContainer.bottomAnchor.constraint(
+                    equalTo: view.keyboardLayoutGuide.topAnchor
+                )
+            ])
+            view.keyboardLayoutGuide.followsUndockedKeyboard = true
+        }
     }
 
     var notificationCenter = NotificationCenter.default

ChattoAdditions/Source/Input/ChatInputBarPresenter.swift

@@ -107,14 +107,23 @@ public class BasicChatInputBarPresenter: NSObject, ChatInputBarPresenter {
     private var lastKnownKeyboardHeight: CGFloat?
     private var allowListenToChangeFrameEvents = true
 
+    /// iOS 26 adds a grabber/separator above custom input views.
+    /// No public API exists to query this value.
+    private var inputViewGrabberHeight: CGFloat {
+        if #available(iOS 26, *) {
+            return 17.0
+        }
+        return 0
+    }
+
     // MARK: Input View
 
     private weak var currentInputView: InputContainerView?
 
     private func updateHeight(for inputView: InputContainerView) {
         inputView.contentHeight = {
             if let keyboardHeight = self.lastKnownKeyboardHeight, keyboardHeight > 0 {
-                return keyboardHeight
+                return keyboardHeight - self.inputViewGrabberHeight
             } else {
                 if UIScreen.main.portraitOrientation {
                     return UIScreen.main.defaultPortraitKeyboardHeight
@@ -135,7 +144,17 @@ public class BasicChatInputBarPresenter: NSObject, ChatInputBarPresenter {
         guard self.focusedItem != nil else { return }
         guard let value = (notification as NSNotification).userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue else { return }
         guard value.cgRectValue.height > 0 else { return }
-        self.lastKnownKeyboardHeight = value.cgRectValue.height - self.chatInputBar.bounds.height
+        var keyboardHeight: CGFloat
+        if #available(iOS 26, *) {
+            // iOS 26 no longer includes the input accessory view (chat bar)
+            // in the reported keyboard frame, so we skip the subtraction.
+            // Note that for custom intput views, the grabber height is still included in the keyboard frame,
+            // so we have to subtract it out.
+            keyboardHeight = value.cgRectValue.height
+        } else {
+            keyboardHeight = value.cgRectValue.height - self.chatInputBar.bounds.height
+        }
+        self.lastKnownKeyboardHeight = keyboardHeight
     }
 
     @objc