final JPanel info = new JPanel(); final JScroll Pane info S = new JScroll Pane(info, Scroll Pane Constants. HORIZONTAL_SCROLLBAR_NEVER); Layout(null); Size(420,600); info Location(10,80); info Size(420,490); gui.add(info S); // gui is the frame's content pane (the overall JPanel) @Thrfoot : A quote from Java Docs "Although it is possible to do without a layout manager, you should use a layout manager if at all possible.
A layout manager makes it easier to adjust to look-and-feel-dependent component appearances, to different font sizes, to a container's changing size, and to different locales.
I solved it, the problem was the JPanel#revalidate, i wasn´t doing it, so, thank you Maneesh.
My main frame contains JScroll Pane which lists some objects. The key will be to update the component being held by the JScroll Pane and then revalidate and repaint this component.
Suzon: Yeah, I tried to put inner Panel.invalidate() and then run scrollpane.repaint() but no luck.