how to automatic restart scanning cloud recognition

hello

how to create a cloud handler script can automatically restart scanning when the target is lost? because on the cloud handler script to restart scanning must press the button restart scanning.

[code]

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using Vuforia;

public class CloudHandler : MonoBehaviour, IObjectRecoEventHandler
{

    private CloudRecoBehaviour mCloudRecoBehaviour;
    private bool mIsScanning = false;
    public static string mTargetMetadata;
    public ImageTargetBehaviour ImageTargetTemplate;
    // Use this for initialization
    void Start()
    {
       
        // register this event handler at the cloud reco behaviour
        mCloudRecoBehaviour = GetComponent<CloudRecoBehaviour>();

        if (mCloudRecoBehaviour)
        {
            mCloudRecoBehaviour.RegisterEventHandler(this);
        }
    }

    public void OnInitialized(TargetFinder targetFinder)
    {
        Debug.Log("Cloud Reco initialized");
    }

    public void OnInitError(TargetFinder.InitState initError)
    {
        Debug.Log("Cloud Reco Init Error" + initError.ToString());
    }

    public void OnUpdateError(TargetFinder.UpdateState updateError)
    {
        Debug.Log("Cloud Reco Update Error" + updateError.ToString());
    }

    public void OnStateChanged(bool scanning)
    {
        mIsScanning = scanning;
        if (scanning)
        {
            // clear all known trackables
            var tracker = TrackerManager.Instance.GetTracker<ObjectTracker>();
            tracker.TargetFinder.ClearTrackables(false);
        }
    }

    // Here we handle a cloud target recognition event
    public void OnNewSearchResult(TargetFinder.TargetSearchResult targetSearchResult)
    {
        TargetFinder.CloudRecoSearchResult cloudRecoSearchResult =
            (TargetFinder.CloudRecoSearchResult)targetSearchResult;
        // do something with the target metadata
        mTargetMetadata = cloudRecoSearchResult.MetaData;
        // stop the target finder (i.e. stop scanning the cloud)
        mCloudRecoBehaviour.CloudRecoEnabled = false;

        if (ImageTargetTemplate)
        {
            // enable the new result with the same ImageTargetBehaviour:
            ObjectTracker tracker = TrackerManager.Instance.GetTracker<ObjectTracker>();
            ImageTargetBehaviour imageTargetBehaviour =
             (ImageTargetBehaviour)tracker.TargetFinder.EnableTracking(
             targetSearchResult, ImageTargetTemplate.gameObject);
        }
    }

    void OnGUI()
    {
        // so that user can restart cloud scanning
        if (!mIsScanning)
        {
            // Display metadata of latest detected cloud-target
            GUI.Box(new Rect(100, 200, 200, 50), mTargetMetadata);
            if (GUI.Button(new Rect(100, 300, 200, 50), "Restart Scanning"))
             {
                // Restart TargetFinder
                mCloudRecoBehaviour.CloudRecoEnabled = true;
             }
        }
    }
}

[/code]