Чтобы добавить в представление распознаватель жестов перетаскивания, вы можете использовать разные подходы в зависимости от платформы, на которой вы работаете. Вот несколько методов с примерами кода для различных платформ:

1. iOS (Swift):

   // Import the required libraries
   import UIKit
   import UIKit.UIGestureRecognizerSubclass
   // Create a custom gesture recognizer
   class DragDownGestureRecognizer: UIPanGestureRecognizer {
   override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent) {
       super.touchesMoved(touches, with: event)
   
       if state == .possible {
           let velocity = self.velocity(in: view)
           if velocity.y > 0 {
               state = .recognized
           }
       }
   }
   }
   // Add the gesture recognizer to your view
   let view = UIView()
   let gestureRecognizer = DragDownGestureRecognizer(target: self, action: #selector(handleDragDownGesture))
   view.addGestureRecognizer(gestureRecognizer)
   // Handle the gesture
   @objc func handleDragDownGesture(_ gestureRecognizer: DragDownGestureRecognizer) {
   if gestureRecognizer.state == .recognized {
       // Drag down gesture recognized, perform actions here
   }
   }

2. Android (Java):

   // Import the required libraries
   import android.content.Context;
   import android.util.AttributeSet;
   import android.view.GestureDetector;
   import android.view.MotionEvent;
   import android.view.View;
   // Create a custom view and implement the drag-down gesture
   public class DragDownView extends View {
   private GestureDetector gestureDetector;
   public DragDownView(Context context, AttributeSet attrs) {
       super(context, attrs);
       gestureDetector = new GestureDetector(context, new DragDownGestureListener());
   }
   @Override
   public boolean onTouchEvent(MotionEvent event) {
       return gestureDetector.onTouchEvent(event);
   }
   private class DragDownGestureListener extends GestureDetector.SimpleOnGestureListener {
       @Override
       public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
           if (distanceY > 0) {
               // Drag down gesture recognized, perform actions here
               return true;
           }
           return false;
       }
   }
   }
   // Add the custom view to your layout XML file
   <com.yourpackage.DragDownView
   android:layout_width="match_parent"
   android:layout_height="match_parent" />

3. Интернет (JavaScript):

   // Add a drag-down event listener to your view
   const view = document.getElementById('your-view-id');
   view.addEventListener('pointermove', handleDragDownGesture);
   function handleDragDownGesture(event) {
   if (event.movementY > 0) {
       // Drag down gesture recognized, perform actions here
   }
   }