using UnityEngine;
using System.Collections;
using UnityEngine.UI;

public class sl : MonoBehaviour {

   public Slider newVl;
   public GameObject test1;


    // Use this for initialization
    public void Start () {

     newVl.onValueChanged.AddListener(delegate { testq();});

    }
    
    // Update is called once per frame
  void Update () {}

    public void testq()
{

Debug.Log("№=" + newVl.value);
   
    }

}

NullReferenceException: Object reference not set to an instance of an object
sl.Start () (at Assets/sl.cs:15)

  Slider qw;
  public GameObject test2;

    // Use this for initialization
    public void Start ()
    {

qw = GetComponentInParent<Slider>();
    }

    public void Update2s()
    {
        
     Debug.Log("№=" + qw.value);
       
   if ((float)qw.value <= 70)
        {
         
          test2. gameObject.GetComponent<ParticleSystem>().Stop();
        }
        else if ((float)qw.value >= 70)
       
        {
          test2.gameObject.GetComponent<ParticleSystem>().Play();
}
          

public void Play(bool withChildren = true);

shtok2.transform.position = new Vector3(0f, 8.0f, 98.4f);
        shtok2.transform.rotation = Quaternion.Euler(0, 0, 0);

* Speed * Time.deltaTime

       Toggle2 = false
            if obj1 = false  obj2 =true  then
                obj1 = false , obj2 =false

        elseif obj1 = true, obj2=false then
                 obj1 = false , obj2 =false

        elseif obj1 = false, obj2=true then
                 obj1 = false , obj2 =false

       toggle2 = true
                if obj1 = false  obj2 =false   then
                obj1 = true , obj2 =false

        elseif obj1 = false, obj2=true then
                 obj1 = true  , obj2 =false

public Toggle tobbl1;
public Toggle tobbl2;
public GameObject obj1;
public  GameObject obj2;

    void Start () {
        obj1.SetActive(false );

    }   
    
    public void Toltest()
    {
      
       if(tobbl2.isOn  == true )
        {

            obj1.SetActive(false);
            obj2.SetActive(true);
           tobbl1.isOn = true;
            
        }
        else if(tobbl2.isOn == false)
        {

            obj1.SetActive(true);
            obj2.SetActive(false);

             tobbl1.isOn = true;
   
        }
    }

    public Toggle tobbl1;
    public Toggle tobbl2;
    public GameObject obj1;
    public GameObject obj2;
  

    public void Toltest()
    {

        if (tobbl1.isOn == true)
        {

          // tobbl1.enabled  = true ;
           if (tobbl2.isOn == true)
           {
               obj1.gameObject.SetActive(false);
               obj2.gameObject.SetActive(true);
           }
           else if (tobbl2.isOn == false)
           {
               obj1.gameObject.SetActive(true);
               obj2.gameObject.SetActive(false);
           }

        }
        else if (tobbl1.isOn == false)
        {

            obj1.gameObject.SetActive(false);
            obj2.gameObject.SetActive(false);
        }
    }
   

public class SwitchObjects : MonoBehaviour {
    private GameObject obj1;
    private GameObject obj2;

    bool isFirstSwitchVisible = true;
    void SwitchObject()
    {
        if (isFirstSwitchVisible == true)
        {
            obj1.enable = false;
            obj2.enable = true;
        }
        else
        {
            obj1.enable = true;
            obj2.enable = false;
        }
    }

}