addded paste method channel in native ios folder (#462)

ios/Runner/AppDelegate.swift

@@ -1,13 +1,42 @@
-import UIKit
 import Flutter
+import UIKit
 
 @main
 @objc class AppDelegate: FlutterAppDelegate {
   override func application(
     _ application: UIApplication,
     didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
   ) -> Bool {
+    // Register the method channel
+    let controller = window?.rootViewController as! FlutterViewController
+    let clipboardImageChannel = FlutterMethodChannel(name: "clipboard_image_channel",
+                                                      binaryMessenger: controller.binaryMessenger)
+
+    clipboardImageChannel.setMethodCallHandler { (call: FlutterMethodCall, result: @escaping FlutterResult) in
+      if call.method == "getClipboardImage" {
+        self.getClipboardImage(result: result)
+      } else {
+        result(FlutterMethodNotImplemented)
+      }
+    }
+
     GeneratedPluginRegistrant.register(with: self)
     return super.application(application, didFinishLaunchingWithOptions: launchOptions)
   }
-}
+
+  private func getClipboardImage(result: FlutterResult) {
+    // Check if the clipboard contains an image
+    if let image = UIPasteboard.general.image {
+      // Convert the image to PNG data
+      if let imageData = image.pngData() {
+        // Encode the image data to a Base64 string
+        let base64String = imageData.base64EncodedString()
+        result(base64String) // Send the Base64 string back to Flutter
+      } else {
+        result(FlutterError(code: "NO_IMAGE", message: "Could not convert image to data", details: nil))
+      }
+    } else {
+      result(FlutterError(code: "NO_IMAGE", message: "Clipboard does not contain an image", details: nil))
+    }
+  }
+}