positiom

Unity Engine
1

my player is in position -2 ,-4 . enemy has speed of -4 in X axis and when collides with player , just moves it in x axis towards left , but i need after colliding both game objects become without movement , i mean still and fix in collision point .how is it possible? Here is my class :

using UnityEngine;
using System.Collections;

public class PlayerAnimationController : MonoBehaviour {

    private Animator anim;


    void Awake()
    {
        anim = GetComponent<Animator> ();

    }

    void OnCollisionEnter2D(Collision2D col)
    {
        if (col.gameObject.tag == "Enemy")
        {
            Debug.Log ("Player");
            var running = false;
            anim.SetBool ("Running", running);

        }
    }
}
2

Grab the Rigidbody2D via GetComponent() from each colliding object and set its X velocity to 0?

3

thanks . another question please :
when i load a scene with SceneManager.LoadScene(2); or go to next scene and come back to the current scene , its always this exception error and cannot find my objectpool prefab instances , how i can fix this problem ?
here is my object pool class

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

public class ObjectPool : MonoBehaviour {

    public RecycleGameObject prefab;

    private List<RecycleGameObject> poolInstances = new List<RecycleGameObject>();

    private RecycleGameObject CreateInstance(Vector3 pos){

        var clone = GameObject.Instantiate (prefab);
        clone.transform.position = pos;
        clone.transform.parent = transform;

        poolInstances.Add (clone);

        return clone;
    }

    public RecycleGameObject NextObject(Vector3 pos){
        RecycleGameObject instance = null;

        foreach (var go in poolInstances) {
            if(go.gameObject.activeSelf != true){
                instance = go;
                instance.transform.position = pos;
            }
        }

        if(instance == null)
            instance = CreateInstance (pos);

        instance.Restart ();

        return instance;
    }

}