Question

I have been going nuts trying to figure this out.

I am trying to elimenate a light blue background that appears in a JTabbedPane. I’ve tried everything and nothing seems to work.

Below is my code. If you run it, it will show the tab, when selected with a light blue background and a thing blue border at the top. I want to control this color. But how?

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.plaf.ColorUIResource;
public class Main extends JFrame {
  JTabbedPane tab=new JTabbedPane();
  public Main() {
     setSize(300,300);
     setTitle("Test Tab pane");
     tab.add("First",new myPanel("First"));
     tab.add("Second",new myPanel("Second"));
     tab.add("Third",new myPanel("Third"));
     tab.add("Fourth",new myPanel("Fourth"));
     tab.addChangeListener(new ChangeTab());
     getContentPane().add(tab,BorderLayout.CENTER);
     setVisible(true);
     for(int i=0;i<tab.getTabCount();i++){
          if(i != tab.getSelectedIndex())
            tab.setBackgroundAt(i,Color.orange);
            tab.setForeground(Color.BLACK);
     }
     tab.setOpaque(true);
     UIManager.put("TabbedPane.contentAreaColor ",ColorUIResource.GREEN);
     UIManager.put("TabbedPane.selected",ColorUIResource.GREEN);
     UIManager.put("TabbedPane.background",ColorUIResource.GREEN);
     UIManager.put("TabbedPane.shadow",ColorUIResource.GREEN);
  }

  public static void main(String[] args) {
    Main main = new Main();
  }

  class ChangeTab implements ChangeListener{
    public void stateChanged(ChangeEvent e){
        tab.validate();
        System.out.println(tab.getSelectedIndex());
        for(int i=0;i<tab.getTabCount();i++){
          if(i != tab.getSelectedIndex())
            tab.setBackgroundAt(i,Color.orange);
        }

    }
  }

  class myPanel extends JPanel{
    public myPanel(String str){
       add(new JLabel(str));
    }
  }

}

Answer 1

I used your example code, and what worked for me was moving the calls to UIManager.put() to a point where they would be executed before the JTabbedPane constructor was executed.

public class Main extends JFrame {
    JTabbedPane tab;

    public Main() {
       // ... other stuff
       UIManager.put("TabbedPane.contentAreaColor ",ColorUIResource.GREEN);
       UIManager.put("TabbedPane.selected",ColorUIResource.GREEN);
       UIManager.put("TabbedPane.background",ColorUIResource.GREEN);
       UIManager.put("TabbedPane.shadow",ColorUIResource.GREEN);

       // now construct the tabbed pane
       tab=new JTabbedPane();

       // ... other stuff
 }

There’s also some other properties available (for the Metal L&F, at least):

UIManager.put("TabbedPane.borderColor", Color.RED);
UIManager.put("TabbedPane.darkShadow", ColorUIResource.RED);
UIManager.put("TabbedPane.light", ColorUIResource.RED);
UIManager.put("TabbedPane.highlight", ColorUIResource.RED);
UIManager.put("TabbedPane.focus", ColorUIResource.RED);
UIManager.put("TabbedPane.unselectedBackground", ColorUIResource.RED);
UIManager.put("TabbedPane.selectHighlight", ColorUIResource.RED);
UIManager.put("TabbedPane.tabAreaBackground", ColorUIResource.RED);
UIManager.put("TabbedPane.borderHightlightColor", ColorUIResource.RED);

These let you control most of the colours in the tab area.

I found with these settings there was still a very small blue-ish grey border around the content. I have searched for how to set this colour to no avail. The only solution I could find to get rid of this was:

UIManager.put("TabbedPane.contentBorderInsets", new Insets(0, 0, 0, 0));

Which is a sub-optimal solution.