Unity Class Inheritance Problems

Question

Hi I am trying to create a game where there are different types of zombies. I decided to create a base class for the zombies that includes methods for moving and flipping characters and then I have individual classes for each type of zombie where I will modify things like health and damage.

I made it so the zombie prefab I put in the game has a script that inherits from the Zombie class but when I run the game nothing in the Zombie.cs script is run.

Anyway, here are my classes:

Zombie.cs

public class Zombie : MonoBehaviour {

    //zombie goes after this target
    Transform targetPlayer; 

    //Zombie Rigid Body
    Rigidbody2D zombieRB; 

    //The speed the zombie will move
    public float moveSpeed;

    //Used for flipping zombie based on which way it is going
    bool facingRight = true;

    // Use this for initialization
    void Start () {

        zombieRB = GetComponent <Rigidbody2D> ();

        //This finds the player object to follow it
        targetPlayer = GameObject.FindGameObjectWithTag ("Player").transform;
    }

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


        //Checks zombies position in comparison to player to see where it should move.
        if (transform.position.x < targetPlayer.position.x) {
            //zombie to the left of target go right

            if (!facingRight) { //Check if needs flipping
                flipZombie ();
            }

            zombieRB.velocity = new Vector2 (moveSpeed, zombieRB.velocity.y);

        } else {
            //zombie to the right of target go left

            if (facingRight) { //Check if needs flipping
                flipZombie ();
            }

            zombieRB.velocity = new Vector2 (moveSpeed * -1, zombieRB.velocity.y);
        }

    }


    /// <summary>
    /// Flips the zombie when moving
    /// </summary>
    void flipZombie() {
        facingRight = !facingRight;
        Vector3 theScale = transform.localScale;
        theScale.x *= -1;
        transform.localScale = theScale;
    }
}

And then I have a pulserZombie.cs but there is nothing in it but the inheritance:

public class pulserMovement : Zombie {

Here is my image of the prefab I have:

Answer 1

By not specifically setting your methods as public, your methods are set to private. They should be set to protected.

When we inherit, we lose access to all private methods and variables. We use protected to say "this is still private from the outside, but it is still accessible through inheritancy".

Note that if you intend to add any extra functionality to a method in your child class, you will also need to set it as virtual, with the child class referencing it as override. You can than write a new method, using base.methodName to call the base version of the method, if needed.

virtual protected void Update() {...}

override protected void Update()
{ 
 ...

 base.Update();
}