Add a menu item to a menu tree, along with sub-menu nodes if needed - Java Swing

Java examples for Swing:JMenu

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Description

Add a menu item to a menu tree, along with sub-menu nodes if needed

Demo Code


//package com.java2s;
import java.util.Arrays;
import java.awt.Component;
import java.awt.event.ActionListener;
import javax.swing.JMenu;
import javax.swing.JMenuItem;

public class Main {
    /**/*from  w  w w .  j  a v a2  s.  c  o  m*/
     * Add a menu item to a menu tree, along with sub-menu nodes if needed
     * 
     * @param labels An array of menu labels where the last String represents
     *               the menu item and all other Strings represent
     *               the sub-menu tree in which the item should be placed
     * @param command The command string to send to the menu listener
     *                when this item is selected
     * @param m The top menu tree to start with
     * @param l The {@code ActionListener} to add to the menu item
     */
    public static void parseRecursiveMenuAdd(String[] labels,
            String command, JMenu m, ActionListener l) {
        if (labels.length == 1) {
            JMenuItem i = new JMenuItem(labels[0].trim());
            i.setActionCommand(command);
            i.addActionListener(l);
            addAlphabetized(i, m, false);
            return;
        }
        Component[] items = m.getMenuComponents();
        if (items != null && items.length > 0) {
            for (int u = 0; u < items.length; u++) {
                if (JMenu.class.isInstance(items[u])
                        && ((JMenu) items[u]).getText().equals(
                                labels[0].trim())) {
                    String[] remainingLabels = Arrays.copyOfRange(labels,
                            1, labels.length);
                    parseRecursiveMenuAdd(remainingLabels, command,
                            (JMenu) items[u], l);
                    return;
                }
            }
        }
        JMenu sm = new JMenu(labels[0].trim());
        sm.setName(labels[0].trim());
        addAlphabetized(sm, m, false);
        String[] remainingLabels = Arrays.copyOfRange(labels, 1,
                labels.length);
        parseRecursiveMenuAdd(remainingLabels, command, sm, l);
    }

    /**
     * Add a menu item to it's proper alphabetized position
     * in the menu. Assumes any existing menu items are
     * already alphabetized.
     * 
     * @param jmi The menu item to add
     * @param jm The menu to which the item should be added
     * @param foldersFirst If {@code true}, add folders before
     *   other items; if {@code false}, add folders after other items.
     */
    private static void addAlphabetized(JMenuItem jmi, JMenu jm,
            boolean foldersFirst) {
        if (jm == null || jmi == null)
            throw new IllegalArgumentException();
        final int n = jm.getItemCount();
        final boolean folder = jmi instanceof JMenu;
        if (n == 0) {
            jm.add(jmi);
            return;
        }
        for (int i = 0; i < n; i++) {
            JMenuItem cur = jm.getItem(i);
            if (cur == null)
                continue;
            boolean curFolder = cur instanceof JMenu;
            if ((foldersFirst && folder && !curFolder)
                    || (!foldersFirst && !folder && curFolder)) {
                jm.insert(jmi, i);
                break;
            }
            if (((folder && curFolder) || (!folder && !curFolder))
                    && jmi.getText().compareToIgnoreCase(cur.getText()) <= 0) {
                jm.insert(jmi, i);
                break;
            }
            if (i == n - 1)
                jm.add(jmi);
        }
    }
}

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