Layout manager for a Windows type toolbar

Question

I have made a layout manager that when there is not enough room to put all the buttons it stores them inside a "subMenu" that appears at the end of the tool bar. Unfortunally the perfered size is not being calculated correctly so when the user makes the toolbar floatable it doesn't make the toolbar long enough.
Here is my code:
* ExpandLayout.java
* Created on May 29, 2003, 3:17 PM
package edu.cwu.virtualExpert.caseRecorder;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
* @author  subanark
public class ExpandLayout implements java.awt.LayoutManager
    private JPopupMenu extenderPopup = new JPopupMenu();
    private JButton extenderButton = new JButton(new PopupAction());
    /** Creates a new instance of ExpandLayout */
    public ExpandLayout()
    protected class PopupAction extends AbstractAction
        public PopupAction()
            super(">");
        public void actionPerformed(ActionEvent e)
            JComponent component = (JComponent)e.getSource();
            extenderPopup.show(component,0,component.getHeight());
    /** If the layout manager uses a per-component string,
     * adds the component <code>comp</code> to the layout,
     * associating it
     * with the string specified by <code>name</code>.
     * @param name the string to be associated with the component
     * @param comp the component to be added
    public void addLayoutComponent(String name, Component comp)
     * Lays out the specified container.
     * @param parent the container to be laid out
    public void layoutContainer(Container parent)
        Dimension parentSize = parent.getSize();
        Dimension prefSize = preferredLayoutSize(parent);
        Insets insets = parent.getInsets();
        int x = insets.left;
        int y = insets.top;
        parentSize.width -= insets.right;
        int i;
        for(int j = 0; j < extenderPopup.getComponentCount();)
            Component aComponent = extenderPopup.getComponent(j);
            parent.add(aComponent);
        parent.remove(extenderButton);
        //System.out.println("Component count:"+parent.getComponentCount());
        for(i = 0; i < parent.getComponentCount() &&
                   parent.getComponent(i).getPreferredSize().width +(i==parent.getComponentCount()-1?0:extenderButton.getPreferredSize().width) + x < parentSize.width;i++)
            //System.out.println("exSize"+(parent.getComponent(i).getPreferredSize().width +extenderButton.getPreferredSize().width + x));
            Component aComponent = parent.getComponent(i);
            if(aComponent != extenderButton)
                aComponent.setSize(aComponent.getPreferredSize());
                aComponent.setLocation(x,y);
                x += aComponent.getPreferredSize().width;
                //System.out.println(aComponent.getX());
        if(i < parent.getComponentCount())
            while(i < parent.getComponentCount())
                //System.out.println("Need Room");
                extenderPopup.add(parent.getComponent(i));
            //System.out.println("extenderButton added");
            parent.add(extenderButton);
            extenderButton.setSize(extenderButton.getPreferredSize());
            extenderButton.setLocation(x,y);
            x += extenderButton.getPreferredSize().width;
            //System.out.println(extenderButton);
        else
            //System.out.println("extenderButton removed");
            parent.remove(extenderButton);
            //System.out.println("Component count:"+extenderButton.getComponentCount());
     * Calculates the minimum size dimensions for the specified
     * container, given the components it contains.
     * @param parent the component to be laid out
     * @see #preferredLayoutSize
    public Dimension minimumLayoutSize(Container parent)
        return extenderButton.getMinimumSize();
    /** Calculates the preferred size dimensions for the specified
     * container, given the components it contains.
     * @param parent the container to be laid out
     * @see #minimumLayoutSize
    public Dimension preferredLayoutSize(Container parent)
        Dimension d = new Dimension();
        d.width += parent.getInsets().right+parent.getInsets().left;
        for(int i = 0; i < parent.getComponents().length;i++)
            if(parent.getComponent(i) != extenderButton)
                d.width+=parent.getComponent(i).getPreferredSize().width;
                d.height = Math.max(d.height,parent.getComponent(i).getPreferredSize().height);
        for(int i = 0; i < extenderPopup.getComponentCount();i++)
            d.width+=extenderPopup.getComponent(i).getPreferredSize().width;
            d.height = Math.max(d.height,extenderPopup.getComponent(i).getPreferredSize().height);
        d.height += parent.getInsets().top+parent.getInsets().bottom+5;
        return d;
    /** Removes the specified component from the layout.
     * @param comp the component to be removed
    public void removeLayoutComponent(Component comp)
    public static void main(String[] argv)
        JFrame f = new JFrame();
        JToolBar toolBar = new JToolBar();
        toolBar.setLayout(new ExpandLayout());
        toolBar.add(new JButton("hello"));
        toolBar.add(new JButton("Hello2"));
        toolBar.add(new JButton("Hello3"));
        toolBar.add(new JButton("Hi"));
        f.getContentPane().setLayout(new BorderLayout());
        f.getContentPane().add(toolBar,BorderLayout.NORTH);
        f.setBounds(0,0,300,300);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setVisible(true);
}

Answer 1

This is a wierd one. I noticed that the width of a button is 22 pixels larger in the popup menu that it is in the toolbar.I traced this down to the insets being changed when the button is added to the toolbar. The strange part is that the size of the component keeps changing as you move it from the toolbar to the popup menu and back.
Anyway, I ended up changing most of you code. Here is my version:
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
* @author subanark
public class ExpandLayout implements java.awt.LayoutManager
     private JPopupMenu extenderPopup = new JPopupMenu();
     private JButton extenderButton = new JButton(new PopupAction());
     /** Creates a new instance of ExpandLayout */
     public ExpandLayout()
     /** If the layout manager uses a per-component string,
     * adds the component <code>comp</code> to the layout,
     * associating it
     * with the string specified by <code>name</code>.
     * @param name the string to be associated with the component
     * @param comp the component to be added
     public void addLayoutComponent(String name, Component comp)
     * Lays out the specified container.
     * @param parent the container to be laid out
     public void layoutContainer(Container parent)
          //  Position all buttons in the container
          Insets insets = parent.getInsets();
          int x = insets.left;
          int y = insets.top;
          int spaceUsed = insets.right + insets.left;
          for (int i = 0; i < parent.getComponentCount(); i++ )
               Component aComponent = parent.getComponent(i);
               aComponent.setSize(aComponent.getPreferredSize());
               aComponent.setLocation(x,y);
               int componentWidth = aComponent.getPreferredSize().width;
               x += componentWidth;
               spaceUsed += componentWidth;
          //  All the buttons won't fit, add extender button
          //  Note: the size of the extender button changes once it is added
          //  to the container. Add it here so correct width is used.
          int parentWidth = parent.getSize().width;
          if (spaceUsed > parentWidth)
               parent.add(extenderButton);
               extenderButton.setSize( extenderButton.getPreferredSize() );
               spaceUsed += extenderButton.getSize().width;
          //  Remove buttons that don't fit and add to the popup menu
          while (spaceUsed > parentWidth)
               int last = parent.getComponentCount() - 2;
               Component aComponent = parent.getComponent( last );
               parent.remove( last );
               extenderPopup.insert(aComponent, 0);
               extenderButton.setLocation( aComponent.getLocation() );
               spaceUsed -= aComponent.getSize().width;
     * Calculates the minimum size dimensions for the specified
     * container, given the components it contains.
     * @param parent the component to be laid out
     * @see #preferredLayoutSize
     public Dimension minimumLayoutSize(Container parent)
          return extenderButton.getMinimumSize();
     /** Calculates the preferred size dimensions for the specified
     * container, given the components it contains.
     * @param parent the container to be laid out
     * @see #minimumLayoutSize
     public Dimension preferredLayoutSize(Container parent)
          //  Move all components to the container and remove the extender button
          parent.remove(extenderButton);
          while ( extenderPopup.getComponentCount() > 0 )
               Component aComponent = extenderPopup.getComponent(0);
               extenderPopup.remove(aComponent);
               parent.add(aComponent);
          //  Calculate the width of all components in the container
          Dimension d = new Dimension();
          d.width += parent.getInsets().right + parent.getInsets().left;
          for (int i = 0; i < parent.getComponents().length; i++)
               d.width += parent.getComponent(i).getPreferredSize().width;
               d.height = Math.max(d.height,parent.getComponent(i).getPreferredSize().height);
          d.height += parent.getInsets().top + parent.getInsets().bottom + 5;
          return d;
     /** Removes the specified component from the layout.
     * @param comp the component to be removed
     public void removeLayoutComponent(Component comp)
     protected class PopupAction extends AbstractAction
          public PopupAction()
               super(">");
          public void actionPerformed(ActionEvent e)
               JComponent component = (JComponent)e.getSource();
               extenderPopup.show(component,0,component.getHeight());
     public static void main(String[] argv)
          JFrame f = new JFrame();
          JToolBar toolBar = new JToolBar();
          toolBar.setLayout(new ExpandLayout());
          toolBar.add(new JButton("hello"));
          JButton button = new JButton("Hello2");
          System.out.println( button.getInsets() );
          toolBar.add(button);
          System.out.println( button.getInsets() );
          toolBar.add(new JButton("Hello3"));
          toolBar.add(new JButton("Hi"));
          f.getContentPane().setLayout(new BorderLayout());
          f.getContentPane().add(toolBar,BorderLayout.NORTH);
          f.setBounds(0,0,300,300);
          f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          f.setVisible(true);
}