Beginnings of a collapsible list class. Presently it doesn't provide UI

elements to collapse and expand.


git-svn-id: https://samskivert.googlecode.com/svn/trunk@648 6335cc39-0255-0410-8fd6-9bcaacd3b74c

projects/samskivert/src/java/com/samskivert/swing/CollapsibleList.java

@@ -0,0 +1,82 @@
+//
+// $Id: CollapsibleList.java,v 1.1 2002/03/12 17:17:38 mdb Exp $
+
+package com.samskivert.swing;
+
+import javax.swing.JLabel;
+import javax.swing.JList;
+import javax.swing.JPanel;
+import javax.swing.ListModel;
+
+/**
+ * Displays a list of components in sections (with section headers) that
+ * can be collapsed. Each section of a list uses a {@link JList} instance
+ * to render the section elements.
+ */
+public class CollapsibleList extends JPanel
+{
+    /**
+     * Constructs an empty collapsible list.
+     */
+    public CollapsibleList ()
+    {
+        // set up our layout manager
+        VGroupLayout gl = new VGroupLayout(VGroupLayout.NONE);
+        gl.setJustification(VGroupLayout.TOP);
+        gl.setOffAxisJustification(VGroupLayout.LEFT);
+        setLayout(gl);
+    }
+
+    /**
+     * Constructs a collapsible list with the supplied section labels and
+     * models.
+     */
+    public CollapsibleList (String[] sections, ListModel[] models)
+    {
+        this(); // set up our layout manager
+
+        for (int i = 0; i < sections.length; i++) {
+            addSection(sections[i], models[i]);
+        }
+    }
+
+    /**
+     * Returns the number of sections.
+     */
+    public int getSectionCount ()
+    {
+        return getComponentCount()/2;
+    }
+
+    /**
+     * Adds a section to this collapsible list.
+     *
+     * @param label the title of the section.
+     * @param model the list model to use for the new section.
+     *
+     * @return the index of the newly added section.
+     */
+    public int addSection (String label, ListModel model)
+    {
+        add(new JLabel(label));
+        add(new JList(model));
+        return getSectionCount()-1;
+    }
+
+    /**
+     * Returns the list object associated with the specified section.
+     */
+    public JList getSectionList (int index)
+    {
+        return (JList)getComponent(index*2+1);
+    }
+
+    /**
+     * Toggles the collapsed state of the specified section.
+     */
+    public void toggleCollapsed (int index)
+    {
+        JList list = getSectionList(index);
+        list.setVisible(!list.isVisible());
+    }
+}