How can we insert multiple tabs into a single JTabbedPane in Java?

In this article, we will learn to insert multiple tabs into a single JTabbedPane in Java. The Java Swing's JTabbedPane enables you to group content into several tabs in one container.

JTabbedPane

A JTabbedPane is a component can extends the JComponent class, and we can able to see only one tab at a time. Each tab is associated with a single component that can be displayed when the tab is selected.

Syntax

Object declaration and instantiation using the Java class JTabbedPane:

 JTabbedPane tabbedPane = new JTabbedPane();

A JTabbedPane can generate a ChangeListener interface when a tab is selected. It is also possible to insert multiple tabs into a single JTabbedPane.

Methods

The important methods of JTabbedPane are:

• addTab()
• fireStateChanged()
• getTabPlacement()
• setSelectedIndex()
• getTabCount()

Inserting multiple tabs into a single JTabbedPane

In the example, we are using the Swing package's JTabbedPane class for managing several tabs in one window. Each tab may contain a different component, like a panel, a label, or a text field.

The following is the step-by-step process to insert multiple tabs into a single JTabbedPane in Java:

Constructor

The constructor constructs the JFrame window with the header "Nested JTabbedPane test".

public NestedJTabbedPaneTest() {
    setTitle("Nested JTabbedPane test");
    setLayout(new BorderLayout());

JTabbedPane Setup

Creates the JTabbedPane named "tabbedPane" and adds it to the center of the JFrame using the borderLayout. Calls createNestedTab() to start creating the nested tabs.

JTabbedPane tabbedPane = new JTabbedPane();
add(BorderLayout.CENTER, tabbedPane);
createNestedTab(tabbedPane, 1);

createNestedTab() Method

The createNestedTab() function recursively constructs nested JTabbedPane components to a depth of 5 levels, with each new tab serving as a parent for the next nested pane, thus forming a hierarchical tabbed structure.

protected void createNestedTab(JTabbedPane jtp, int count) {
    if (count > 5) return;
    JTabbedPane tp = new JTabbedPane();
    tp.setTabPlacement(getNextOrientation(jtp.getTabPlacement()));
    jtp.addTab("Tab #" + count, tp);
    createNestedTab(tp, count+1);
}

Example

Below is an example for inserting multiple tabs into a single JTabbedPane in Java:

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class NestedJTabbedPaneTest extends JFrame {
   public NestedJTabbedPaneTest() {
      setTitle("Nested JTabbedPane test");
      setLayout(new BorderLayout());
      JTabbedPane tabbedPane = new JTabbedPane();
      add(BorderLayout.CENTER, tabbedPane);
      createNestedTab(tabbedPane, 1);
      setSize(375, 250);
      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      setLoc*ationRelativeTo(null);
      setVisible(true);
   }
   protected void createNestedTab(JTabbedPane jtp, int count) {
      if (count > 5) return;
      JTabbedPane tp = new JTabbedPane();
      tp.setTabPlacement(getNextOrientation(jtp.getTabPlacement()));
      jtp.addTab("Tab #" + count, tp);
      createNestedTab(tp, count+1);
   }
   private int getNextOrientation(int tabPlacement) {
      if (tabPlacement == JTabbedPane.TOP) return JTabbedPane.RIGHT;
      if (tabPlacement == JTabbedPane.RIGHT) return JTabbedPane.BOTTOM;
      if (tabPlacement == JTabbedPane.BOTTOM) return JTabbedPane.LEFT;
      else return JTabbedPane.TOP;
   }
   public static void main(String []args) {
      new NestedJTabbedPaneTest();
   }
}

Output