ATCS/src/com/gpl/rpg/atcontentstudio/ui/CollapsiblePanel.java

package com.gpl.rpg.atcontentstudio.ui;

import javax.swing.*;
import javax.swing.border.TitledBorder;
import java.awt.*;
import java.awt.event.*;

public class CollapsiblePanel extends JPanel {

    private static final long serialVersionUID = 319384990345722150L;

    String title;
    TitledBorder border;

    public CollapsiblePanel(String title) {
        super();
        this.title = title;
        border = BorderFactory.createTitledBorder(title);
        setBorder(border);
        BorderLayout borderLayout = new BorderLayout();
        setLayout(borderLayout);
        addMouseListener(mouseListener);
    }

    MouseListener mouseListener = new MouseAdapter() {
        @Override
        public void mouseClicked(MouseEvent e) {
            toggleVisibility();
        }
    };

    ComponentListener contentComponentListener = new ComponentAdapter() {
        @Override
        public void componentShown(ComponentEvent e) {
            updateBorderTitle();
        }

        @Override
        public void componentHidden(ComponentEvent e) {
            updateBorderTitle();
        }
    };

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        String oldTitle = this.title;
        this.title = title;
        firePropertyChange("title", oldTitle, this.title);
        updateBorderTitle();
    }

    @Override
    public Component add(Component comp) {
        comp.addComponentListener(contentComponentListener);
        Component r = super.add(comp);
        updateBorderTitle();
        return r;
    }

    @Override
    public Component add(String name, Component comp) {
        comp.addComponentListener(contentComponentListener);
        Component r = super.add(name, comp);
        updateBorderTitle();
        return r;
    }

    @Override
    public Component add(Component comp, int index) {
        comp.addComponentListener(contentComponentListener);
        Component r = super.add(comp, index);
        updateBorderTitle();
        return r;
    }

    @Override
    public void add(Component comp, Object constraints) {
        comp.addComponentListener(contentComponentListener);
        super.add(comp, constraints);
        updateBorderTitle();
    }

    @Override
    public void add(Component comp, Object constraints, int index) {
        comp.addComponentListener(contentComponentListener);
        super.add(comp, constraints, index);
        updateBorderTitle();
    }

    @Override
    public void remove(int index) {
        Component comp = getComponent(index);
        comp.removeComponentListener(contentComponentListener);
        super.remove(index);
    }

    @Override
    public void remove(Component comp) {
        comp.removeComponentListener(contentComponentListener);
        super.remove(comp);
    }

    @Override
    public void removeAll() {
        for (Component c : getComponents()) {
            c.removeComponentListener(contentComponentListener);
        }
        super.removeAll();
    }

    protected void toggleVisibility() {
        toggleVisibility(hasInvisibleComponent());
    }

    protected void toggleVisibility(boolean visible) {
        for (Component c : getComponents()) {
            c.setVisible(visible);
        }
        updateBorderTitle();
    }

    protected void updateBorderTitle() {
        String arrow = "";
        if (getComponentCount() > 0) {
            arrow = (hasInvisibleComponent() ? "[+] " : "[-] ");
        }
        border.setTitle(arrow + title);
        repaint();
    }

    protected final boolean hasInvisibleComponent() {
        for (Component c : getComponents()) {
            if (!c.isVisible()) {
                return true;
            }
        }
        return false;
    }

    public void collapse() {
        toggleVisibility(false);
    }

    public void expand() {
        toggleVisibility(true);
    }

    public void setExpanded(boolean expand) {
        toggleVisibility(expand);
    }

}