Scroll Horizontal on Android Canvas

I'm working with the Canvas class and I have several problems.

I have a class called Workbench that extends the View class to use it as a canvas.

On the canvas there are X squares and I can drag them across the screen. I have added the function so that it can be done as a horizontal scroll, which actually increases or decreases the coordinate of the X axis of each object on the canvas, and this is where it fails. When I scroll from left to right, all the objects move well and follow the same positional relationship they had, but when I do it from right to left and the objects reach the limit of the screen they do not move.

If I do it fast if they exceed the limit but if it is done slowly, they remain in the limit and they all get together.

Workbench Class:

public class Workbench extends View {
    public Point puntoMedio;
    public int lastPosX =0;
    List<Objeto> objetoList = new ArrayList<Objeto>();
    int seleccionado = 0;
    public Workbench(Context context) {
        super(context);
        puntoMedio = new Point(0,0);
        for(int i=0;i<5;i++){
            Objeto o = new Objeto();
            o.coordenada.set(10,10);
            objetoList.add(o);
        }

    }

    @Override
    protected void onDraw(Canvas c) {
        super.onDraw(c);
        int HEIGHT = c.getHeight(),WIDTH = c.getWidth();

        Paint p = new Paint();
        p.setColor(Color.RED);
        c.drawRect(0,0,WIDTH,HEIGHT,p);
        dibujar(c);
        invalidate();
    }

    private void dibujar(Canvas c){
        int HEIGHT = c.getHeight(),WIDTH = c.getWidth();
        for(Objeto o:objetoList){
            Paint p = new Paint();
            p.setColor(Color.YELLOW);
            //c.drawCircle(o.coordenada.x,o.coordenada.y,30,p);
            c.drawRect(o.coordenada.x,o.coordenada.y,o.coordenada.x+30,o.coordenada.y+30,p);
            //c.drawRect(o.coordenada.x,o.coordenada.y,100,100,p);
        }
    }

    public void onDragEvent(int x,int y) {
        String datos = String.valueOf(x)+","+String.valueOf(y);
        Log.d("Inicio",datos);

        puntoMedio.set(x,y);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        String datos = String.valueOf(event.getX())+","+String.valueOf(event.getY());
        puntoMedio.set(((int) event.getX()), ((int) event.getY()));

        seleccionado = obtenerTocado(new Point(((int) event.getX()), ((int) event.getY())));
        //Log.d("Seleccionado",String.valueOf(seleccionado));

        if(seleccionado <= objetoList.size()){
            objetoList.get(seleccionado).coordenada.set(((int) event.getX()), ((int) event.getY()));
        } else {
            // Detectr izq o der
            if(event.getX()-lastPosX>0 & lastPosX!=0){
                //Derecha
                for(Objeto o:objetoList){
                    o.coordenada.x +=event.getX()-lastPosX;
                }

            }else if (lastPosX!=0){
                //Izq
                for(Objeto o:objetoList){
                    o.coordenada.x -= -1*(event.getX()-lastPosX);
                }

            }
            lastPosX = (int)event.getX();
        }
        if (event.getAction() == android.view.MotionEvent.ACTION_DOWN) {
            Log.d("TouchTest", "Touch down");
        } else if (event.getAction() == android.view.MotionEvent.ACTION_UP) {
            Log.d("TouchTest", "Touch up");
            lastPosX = 0;
        }
        return super.onTouchEvent(event);
    }
    private int obtenerTocado(Point punto){
        int out = 10;
        Log.d("Seleccionado","Punto tocado:("+punto.x+","+punto.y+")");
        for(int i=0;i<objetoList.size();i++){
            Objeto o = objetoList.get(i);
            Log.d("Seleccionado","Objeto pos: ("+o.coordenada.x+","+o.coordenada.y+")");
            if(punto.x-o.coordenada.x<=o.bounds[2]&punto.x-o.coordenada.x>=o.bounds[0]){
                if(punto.y-o.coordenada.y<=o.bounds[1]){
                    if(punto.y-o.coordenada.y>=o.bounds[3]){
                        return i;
                    }
                }
            }
        }

        return out;
    }

}

Method onCreate in the MainActivity:

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        final Workbench workbench = new Workbench(this);
        setContentView(workbench);
       workbench.setOnLongClickListener(new View.OnLongClickListener() {
           @Override
           public boolean onLongClick(View view) {
                Log.d("CANV","INICIO");
               workbench.onDragEvent((int)view.getX(),(int)view.getY());
               return false;
           }
       });

    }

Object Class:

public class Objeto {
    Point coordenada = new Point();
    int bounds[] = {-50,30,50,-30};
}