init

ios/Classes/KeyboardHeightPlugin.swift

@@ -0,0 +1,47 @@
+import Flutter
+import UIKit
+
+public class KeyboardHeightPlugin: NSObject, FlutterPlugin, FlutterStreamHandler {
+  private var eventSink: FlutterEventSink?
+  private var eventChannel: FlutterEventChannel?
+
+  public static func register(with registrar: FlutterPluginRegistrar) {
+    let instance = KeyboardHeightPlugin()
+    instance.eventChannel = FlutterEventChannel(name: "keyboardHeightEventChannel", binaryMessenger: registrar.messenger())
+    instance.eventChannel?.setStreamHandler(instance)
+  }
+
+  public func onListen(withArguments arguments: Any?, eventSink events: @escaping FlutterEventSink) -> FlutterError? {
+    eventSink = events
+    registerKeyboardObservers()
+    return nil
+  }
+
+  public func onCancel(withArguments arguments: Any?) -> FlutterError? {
+    eventSink = nil
+    unregisterKeyboardObservers()
+    return nil
+  }
+
+  private func registerKeyboardObservers() {
+    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow(notification:)), name: UIResponder.keyboardWillShowNotification, object: nil)
+    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide(notification:)), name: UIResponder.keyboardWillHideNotification, object: nil)
+  }
+
+  private func unregisterKeyboardObservers() {
+    NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillShowNotification, object: nil)
+    NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillHideNotification, object: nil)
+  }
+
+  @objc private func keyboardWillShow(notification: NSNotification) {
+    if let userInfo = notification.userInfo,
+       let keyboardFrame = userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? CGRect {
+      eventSink?(NSNumber(value: keyboardFrame.height))
+    }
+  }
+
+  @objc private func keyboardWillHide(notification: NSNotification) {
+    eventSink?(NSNumber(value: 0.0))
+  }
+}
+