java - How to make a Frame with Multiple Panels Like this -

i tried layout shows 1 panel. need leftpanel (panel 1) bit smaller second panel. showing menu , panel 1 in center.

i tried of every layout examples, still not panel 2 show.

i humbly await advice may resolve issue.

public printbillpanel() {     gridlayout lay1 = new gridlayout(0, 2, 10, 5);     mainpanel = new jpanel();     mainpanel.setlayout(new boxlayout(mainpanel, boxlayout.x_axis));     printbill = new jpanel();     showbill = new jpanel();     printbill.setlayout(lay1);     mainpanel.add(printbill);     mainpanel.add(showbill);     mainpanel.setvisible(false); } 

you didn't set sizes of either panel 0 size. didn't make panels visually distinct. not sure why setting mainpanel invisible. after setting sizes , background panels distinguished code worked.

java.awt.eventqueue.invokelater(() ->  {     jframe frm = new jframe();     jpanel mainpanel = new jpanel();     frm.add(mainpanel);     boxlayout layout = new boxlayout(mainpanel, boxlayout.x_axis);     mainpanel.setlayout(layout);     jpanel panel1 = new jpanel();     panel1.setbackground(color.red);     panel1.setpreferredsize(new dimension(100, 300));     mainpanel.add(panel1);     jpanel panel2 = new jpanel();     panel2.setbackground(color.blue);     panel2.setpreferredsize(new dimension(200, 300));     mainpanel.add(panel2);     frm.add(mainpanel);     frm.pack();     frm.setvisible(true); });