Sprite is not attached with a body in libgdx - libgdx

Question

I want the sprite to get attached with a polygon shape body. When I run the code, both the sprite and body is getting displayed but they are not linked with each other. I looked at all the stack overflow questions but nothing helped.
I am creating this in a class and I am instantiating this from main class.
This is my code,
public SpriteButtons(PlayScreen screen) {
this.world = screen.getWorld();
batch = new SpriteBatch();
region = new TextureRegion(screen.getAtlas().findRegion("fireball"), 0, 0, 16, 16);
sprite = new Sprite(region);
this.gamecame = new OrthographicCamera();
BodyDef bodyDef = new BodyDef();
bodyDef.type = BodyDef.BodyType.StaticBody;
bodyDef.position.set(0, 0);
body = world.createBody(bodyDef);
PolygonShape shape = new PolygonShape();
shape.setAsBox(0.2f, 0.2f);
FixtureDef fixtureDef = new FixtureDef();
fixtureDef.shape = shape;
fixtureDef.density = 1f;
sprite.setSize(25, 25);
Fixture fixture = body.createFixture(fixtureDef);
}
public OrthographicCamera getGamecame() {
return gamecame;
}
public void render(float dt) {
sprite.setPosition(body.getPosition().x - sprite.getWidth()/2f,
body.getPosition().y - sprite.getHeight()/2f );
Gdx.app.log("" + body.getPosition().x, "");
batch.begin();
sprite.draw(batch);
setRegion(region);
batch.end();
}
My output is as follows,
The badlogic sprite is not getting attached with a polygon body and I am instantiating this class from main class and I will be calling this class render method from main class render method. Sorry if the question seems stupid. I don't know where I am missing this. Please help..!! Thanks in advance..!!

Answer 1

You must update sprite's position according to the body position in the render method - if you are not doing this how the sprite can know that it is attached to body?
Please notice that box2d body's origin is in the center of the body when libgdx'es sprite's origin is at it's left botto corner. Then you need to subtract half of width and height of body's position.
So this is what you've got to do:
//render()
sprite.setPosition(body.getPosition().x - sprite.getWidth()/2f,
body.getPosition().y - sprite.getHeight()/2f );
...
sprite.draw(batch);
...

Answer 2

try doing this
batch.draw(sprite, sprite.getX(), sprite.getY()); and change body's inital postion somewher above,so that it fall and you can check under gravity by initializing world like world = new World(new Vector2(0, -98f), true);