NGUI: Draggable Camera and Scroll Panel

Hey Guys!

Iam having a problem... I wanted to create an RTS kind of Game so i need a Draggable Camera. For the Troop Selection i wanted to use a Scrollable List.

now my biggest problem is, that when i use the scroll list, the whole background is scrolling. i think you can see the issue pretty clear when you look at this example:

http://pixelpizza.de/unity/nguidrag.html

does anybody know how i can solve this issue?

the code for the scroll view is the following:

 using UnityEngine;
 using System.Collections;
  
 public class ViewDrag : MonoBehaviour {
     Vector3 hit_position = Vector3.zero;
     Vector3 current_position = Vector3.zero;
     Vector3 camera_position = Vector3.zero;
     float z = 0.0f;
  
     // Use this for initialization
     void Start () {
  
     }
  
     void Update(){
        if(Input.GetMouseButtonDown(0)){
          hit_position = Input.mousePosition;
          camera_position = transform.position;
  
        }
        if(Input.GetMouseButton(0)){
          current_position = Input.mousePosition;
          LeftMouseDrag();        
        }
     }
  
     void LeftMouseDrag(){
        current_position.z = hit_position.z = camera_position.y;
  
        Vector3 direction = Camera.main.ScreenToWorldPoint(current_position) - Camera.main.ScreenToWorldPoint(hit_position);
  
        // Invert direction to that terrain appears to move with the mouse.
        direction = direction * -1;
  
        Vector3 position = camera_position + direction;
  
        transform.position = position;
     }
 }