import java.awt.*;
import javax.swing.*;
import java.awt.event.*;

public class Volume extends JPanel implements MouseWheelListener{

	int pos=0;

	public Volume(){
		super();
	}

	protected void paintComponent(Graphics pinceau) {
    // obligatoire : on cree un nouveau pinceau pour pouvoir le modifier plus tard
    Graphics pinceau2 = pinceau.create();
    	if (this.isOpaque()) {
      	// obligatoire : on repeint toute la surface avec la couleur de fond
      	pinceau2.setColor(Color.DARK_GRAY);
      	pinceau2.fillRect(0, 0, this.getWidth(), this.getHeight());
    	} for(int i=0; i<pos; i++){
    		pinceau2.setColor(Color.ORANGE);
    		pinceau2.fillOval((this.getWidth()/33)+(this.getWidth()/31)*3*i, this.getHeight()/4, (this.getWidth()/31)*2, this.getHeight()/2);
    	} for(int j=pos; j<10; j++){
    		pinceau2.setColor(Color.GRAY);
    		pinceau2.fillOval((this.getWidth()/33)+(this.getWidth()/31)*3*j, this.getHeight()/4, (this.getWidth()/31)*2, this.getHeight()/2);
    	}
	}

	public void mouseWheelMoved(MouseWheelEvent e){
		int mv = e.getWheelRotation();
		if (mv>0){
			if(pos==0){
			}
			else{
				pos--;
				this.repaint();
			}
		}
		if (mv<0){
			if(pos==10){
			}
			else{
				pos++;
				this.repaint();
			}
		}
	}
}