Main.java Source code

Introduction

Here is the source code for Main.java

Source

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;
import javax.swing.tree.TreeNode;
import javax.swing.tree.TreePath;

public class Main extends JPanel {

    DefaultMutableTreeNode root = new DefaultMutableTreeNode("root", true),
            node1 = new DefaultMutableTreeNode("node 1", true), node2 = new DefaultMutableTreeNode("node 2", true),
            node3 = new DefaultMutableTreeNode("node 3", true);

    MyJTree tree = new MyJTree(root);

    public Main() {
        root.add(node1);
        node1.add(node2);
        root.add(node3);
        setLayout(new BorderLayout());
        add(new JScrollPane((JTree) tree), "Center");
    }

    public static void main(String s[]) {
        JFrame frame = new JFrame("Tree With Popup");
        Main panel = new Main();

        frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
        frame.setBackground(Color.lightGray);
        frame.getContentPane().add(panel, "Center");

        frame.setSize(panel.getPreferredSize());
        frame.setVisible(true);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
}

class MyJTree extends JTree implements ActionListener {
    JPopupMenu popup = new JPopupMenu();
    JMenuItem mi = new JMenuItem("Insert a children");

    MyJTree(DefaultMutableTreeNode dmtn) {
        super(dmtn);
        mi.addActionListener(this);
        mi.setActionCommand("insert");
        popup.add(mi);
        mi = new JMenuItem("Remove this node");
        mi.addActionListener(this);
        mi.setActionCommand("remove");
        popup.add(mi);
        addMouseListener(new MouseAdapter() {
            public void mouseReleased(MouseEvent e) {
                if (e.isPopupTrigger()) {
                    popup.show((JComponent) e.getSource(), e.getX(), e.getY());
                }
            }
        });

    }

    public void actionPerformed(ActionEvent ae) {
        DefaultMutableTreeNode dmtn, node;

        TreePath path = this.getSelectionPath();
        dmtn = (DefaultMutableTreeNode) path.getLastPathComponent();
        if (ae.getActionCommand().equals("insert")) {
            node = new DefaultMutableTreeNode("children");
            dmtn.add(node);
            ((DefaultTreeModel) this.getModel()).nodeStructureChanged((TreeNode) dmtn);
        }
        if (ae.getActionCommand().equals("remove")) {
            node = (DefaultMutableTreeNode) dmtn.getParent();
            int nodeIndex = node.getIndex(dmtn);
            dmtn.removeAllChildren();
            node.remove(nodeIndex);
            ((DefaultTreeModel) this.getModel()).nodeStructureChanged((TreeNode) dmtn);
        }
    }
}