android - Why does the Texture from AssetManager displays black rectangles only (LibGDX)?

I loaded and get a texture from assetmanager but whenever I test the app it only shows black rectangles instead of the texture. I tried finding some probable cause for this in my code but I can't find any. Here's my code:

MainGame.java

public class MainGame  extends Game {

...
...
@Override
    public void create () {

        EnemyAssets.load();
        EnemyAssets.manager.finishLoading();
        screenWidth = Gdx.graphics.getWidth();
        screenHeight = Gdx.graphics.getHeight();
        camera = new OrthographicCamera();
        camera.setToOrtho(false,screenWidth, screenHeight);
        batch = new SpriteBatch();
}

@Override

    public void render () {

        super.render();
        batch.begin();
        batch.end();
    }

    @Override
    public void dispose () {
        batch.dispose();

        EnemyAssets.dispose();
    }

EnemyAnimation.java: (Here is where I get the asset from AssetsManager)

public class EnemyAnimation extends Actor{

    MainGame app;
    LevelOneScreen levelOneScreen;

    private Animation enemyAnimation;

    private static final int  FRAME_COLS_WALK = 10;
    private static final int  FRAME_ROWS_WALK= 1;
    public TextureRegion   currentFrame;
    public float enemyW;
    public float enemyH;
    public float enemyWidth;
    public float enemyHeight;
    private float stateTime = 0f;

    public float enemyX;

    public float enemyY;
    final float delta = Gdx.graphics.getDeltaTime();

    public float enemyXBound;
    public float enemyYBound;

public EnemyAnimation(final MainGame app) {
        this.app = app;
        this.enemyX = enemyX;
        this.enemyY = enemyY;

        Texture enemySprite = EnemyAssets.manager.get("enemySprite.png",Texture.class);
        enemySprite.setFilter(Texture.TextureFilter.MipMapLinearNearest,Texture.TextureFilter.MipMapLinearNearest);


        TextureRegion[][] tmp = TextureRegion.split(enemySprite, (int) enemySprite.getWidth() / FRAME_COLS_WALK, (int) enemySprite.getHeight() / FRAME_ROWS_WALK);
        TextureRegion[] enemyTexRegion = new TextureRegion[FRAME_COLS_WALK * FRAME_ROWS_WALK];
        int index = 0 ;
        for (int i = 0; i < FRAME_ROWS_WALK; i++) {
            for (int j = 0; j < FRAME_COLS_WALK; j++) {
                enemyTexRegion[index++] = tmp[i][j];

            }
        }

        enemyAnimation = new Animation(0.044f,enemyTexRegion);
        currentFrame = enemyAnimation.getKeyFrame(stateTime, true);
        enemyW = currentFrame.getRegionWidth();
        enemyH= currentFrame.getRegionHeight();
        enemyXBound = getX();
        enemyYBound = getY();
        enemyWidth = app.screenWidth*0.166667f;

        enemyHeight = enemyWidth *(enemyH/enemyW);

        this.setSize(enemyWidth, enemyHeight);
        this.setBounds(enemyXBound,enemyYBound,enemyWidth,enemyHeight);
        this.isTouchable();




    }


 public void draw(Batch batch, float parentAlpha) {

        super.draw(batch, parentAlpha);

        final float delta = Gdx.graphics.getDeltaTime();


        stateTime += delta;


        TextureRegion currentFrame = enemyAnimation.getKeyFrame(stateTime, true);


        batch.draw(currentFrame,getX(),getY(),enemyWidth,enemyHeight);

    }
}

EnemyAssets.java (Here is my AssetsManager)

public class EnemyAssets {


    public static final AssetManager manager = new AssetManager();

    public static void load(){
        manager.load("enemySprite.png",Texture.class);
    }
    public static void dispose(){
        manager.dispose();
    }
}

LevelOneScreen.java

public class LevelOneScreen implements Screen {

    public MainGame app;
    private Stage stage;
    private Stage stageNinja;
    public EnemyAnimation enemyAnimation;
    private float deltaTime = Gdx.graphics.getDeltaTime();


    public Array enemyAnimate;


public LevelOneScreen(final MainGame app){
    this.app = app;
    this.stage = new Stage(new StretchViewport(app.screenWidth, app.screenHeight, app.camera));
    this.stageNinja = new Stage(new StretchViewport(app.screenWidth, app.screenHeight, app.camera));
    enemyAnimate = new Array();
    enemyAnimate.add(new EnemyAnimation(app));
    enemyAnimation = new EnemyAnimation(app);

}


@Override
public void show() {

    InputMultiplexer inputMultiplexer = new InputMultiplexer();
    inputMultiplexer.addProcessor(stage);
    inputMultiplexer.addProcessor(stageNinja);
    Gdx.input.setInputProcessor(inputMultiplexer);



    enemyAct1();

}


public void enemyAct1(){

    for(int i = 1; i < 6; i++){enemyAnimate.add(new EnemyAnimation(app));}


    enemyAnimate.get(1).setPosition(app.screenWidth*0.1f,app.screenHeight);

    stageNinja.addActor(enemyAnimate.get(1));
        enemyAnimate.get(1).addAction(moveTo(app.screenWidth*0.1f,enemyDestination,enemyTimeDrop1));


    enemyAnimate.get(2).setPosition(app.screenWidth*0.1f+enemyAnimation.enemyWidth,app.screenHeight+enemyAnimation.enemyHeight);
        stageNinja.addActor(enemyAnimate.get(2));
   enemyAnimate.get(2).addAction(moveTo(app.screenWidth*0.1f+enemyAnimation.enemyWidth,enemyDestination,enemyTimeDrop2));



    enemyAnimate.get(3).setPosition(app.screenWidth*0.1f+enemyAnimation.enemyWidth*2f,app.    stageNinja.addActor(enemyAnimate.get(3)); enemyAnimate.get(3).addAction(moveTo(app.screenWidth*0.1f+enemyAnimation.enemyWidth*2f,enemyDestination,enemyTimeDrop3));

}


@Override
public void render(float delta) {



    Gdx.gl.glClearColor(0, 0, 0, 1);
    Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);

    update(delta);
}

public void update(float deltaTime){

    stage.draw();

    stageNinja.draw();

    stage.act(deltaTime);
    stageNinja.act(deltaTime);

    app.batch.begin();
    app.batch.end();

}



@Override
public void resize(int width, int height) {
    app.camera.setToOrtho(false, app.screenWidth, app.screenHeight);
    app.camera.update();
    stage.getViewport().setScreenSize(app.screenWidth, app.screenHeight);
    stageNinja.getViewport().setScreenSize(app.screenWidth, app.screenHeight);
}

    @Override

    public void dispose() {
        stage.dispose();
        stageNinja.dispose();

    }
}