java - swing gui flickering white error -

i have gui i'm making program has outer container centered jframe contains inner container holds 22*12 cells. when run program, background flickers white , stays that. if point me out i'm going wrong awesome!

public class gui extends jframe {    private jpanel outer, inner; private jlabel[][] labels = new jlabel[22][12];  public gui() {     setbackground(color.black);     setsize(1000,1000);     setdefaultcloseoperation(jframe.exit_on_close);     setlayout(new borderlayout());      outer = new jpanel();     outer.setlayout(new borderlayout());     outer.setsize(620,920);     outer.setbackground(color.white);      inner = new jpanel();     inner.setlayout(new gridlayout(22,12,10,10));     inner.setsize(600,900);     inner.setbackground(color.white);      (int = 0; < 22; i++)     {         (int j = 0; j < 12; j++)         {             labels[i][j] = new jlabel();             jlabel label = labels[i][j];             label.setsize(50,50);             label.setbackground(color.gray);             inner.add(label);         }     }      outer.add(inner, borderlayout.center);     add(outer, borderlayout.center);     } } 

the gui set visible in main class instantiates it.

the gui created , sized correctly. starts out black background randomly turns white after , stays that.

edit: if still important:

public static void main(string[] args) {     swingutilities.invokelater(new runnable()     {          public void run()         {             gui gui = new gui();             gui.setvisible(true);         }     }); } 

use new static variable names follow final static naming convention. variable should upper cased:

//setbackground(color.black); setbackground(color.black); 

don't use setsize() components. instead add components frame , use pack() method components displayed @ preferred size:

//setsize(1000,1000); add(component1); add(anothercomponent); pack(); 

layout managers use preferred size not size layout tip:

//label.setsize(50,50); label.setpreferredsize(new dimension(50, 50)); 

this main problem. jlabel transparent default, background color set ignored:

label.setbackground(color.gray); label.setopaque(true); 

by way, screen height 738, won't event able see entire frame since want height of 22*50. should aware of , add panel jscrollpane people me can use application. why should not hardcode preferred size.