Draw more sprite but they disappear

Question

I have a array of sprite in a class "Enemy", I want to draw enemies in some positions, but when I draw one, the previous one disappears.

public class Level1 implements Screen{

   Vector2 position;
   private Enemy enemies = new Enemy();

   public Level1 (NameGame game){
      this.game = game;
    
      position = new Vector2(300,100);
      enemies.nemici();

And this is my for loop:

    for (i=0;i<enemies.enemy.size;i++){
    //Maybe i need for (Sprite s : enemy)
        game.batch.draw(enemies.enemy.get(i),position.x,position.y,100,100);
    }

It's only a test to draw enemy, after i will try to draw in more position

If i change position.x and position.y every iteration, for example with position = new Vector2(..,..) after the "game.batch.draw", the previous enemy disappear, but why? How can i draw all?

And this is my enemy class:

package com.mygdx.game;

import com.badlogic.gdx.graphics.Texture;
import com.badlogic.gdx.graphics.g2d.Sprite;
import com.badlogic.gdx.utils.Array;

public class Enemy {
    public Array<Sprite> enemy = new Array<Sprite>(14);   

public void nemici() {
    
    //Inizializzo e aggiungo i nemici all'array
    Sprite mysterio, boss, doctorstrange, electro, goblin, ironman, lizard, mj, ned, octopus, rhyno, sandman, scorpion, scorpion2, venom;
    enemy.add(mysterio = new Sprite(new Texture("mysterio.png")));
    enemy.add(boss = new Sprite(new Texture("boss.png")));
    enemy.add(doctorstrange = new Sprite(new Texture("doctorstrange.png")));
    enemy.add(electro = new Sprite(new Texture("electro.png")));
    enemy.add(goblin = new Sprite(new Texture("goblin.png")));
    enemy.add(ironman = new Sprite(new Texture("ironman.png")));
    enemy.add(lizard = new Sprite(new Texture("lizard.png")));
    enemy.add(mj = new Sprite(new Texture("mj.png")));
    enemy.add(ned = new Sprite(new Texture("ned.png")));
    enemy.add(octopus = new Sprite(new Texture("octopus.png")));
    enemy.add(rhyno = new Sprite(new Texture("rhyno.png")));
    enemy.add(sandman = new Sprite(new Texture("sandman.png")));
    enemy.add(scorpion = new Sprite(new Texture("scorpion.png")));
    enemy.add(scorpion2 = new Sprite(new Texture("scorpion2.png")));
    enemy.add(venom = new Sprite(new Texture("venom.png")));       
    
}

}

Answer 1

You have many enemy sprites, but only one position variable.

In your loop, you take turns to draw every sprite at the same position, so they stack up and you see only one.

You do not want an instance of the enemy class to have several sprites but no position, while the single enemy position is owned by the level. This makes no logical sense whatsoever.

What you want is that a level contains many enemies, and each enemy has one sprite and one position of its own.

public class Enemy {
    public Sprite sprite;  
    public Vector2 position;

    public Enemy(Sprite sprite, Vector2 position) {
        this.sprite = sprite;
        this.position = position;
    }
}

public class Level1 implements Screen {

    private Array<Enemy> enemies;  

    public void makeEnemies() {

        enemies = new Array<Enemy>(14);            
        
        enemies.add(new Enemy(
               new Sprite(new Texture("mysterio.png")), 
               new Vector2(100, 100)
        ));

        enemies.add(new Enemy(
               new Sprite(new Texture("boss.png")), 
               new Vector2(200, 100)
        ));
        // ...
    }

Then your loop draws each enemy at its own position:

for (i=0;i < enemies.size; i++){
    Enemy enemy = enemies.get(i);
    game.batch.draw(
        enemy.sprite,
        enemy.position.x, enemy.position.y,
        100,              100
    );
}