Sort of like a collapsable list, only we have real components inside of

us that can be laid out anywhichway.


git-svn-id: https://samskivert.googlecode.com/svn/trunk@789 6335cc39-0255-0410-8fd6-9bcaacd3b74c

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

@@ -0,0 +1,98 @@
+//
+// $Id: CollapsiblePanel.java,v 1.1 2002/07/04 04:42:11 ray Exp $
+
+package com.samskivert.swing;
+
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+
+import javax.swing.JPanel;
+import javax.swing.JButton;
+
+/**
+ * A panel that contains a button which will collapse the rest of the content.
+ */
+public class CollapsiblePanel extends JPanel
+    implements ActionListener
+{
+    /**
+     * Construct a collapsible panel with the specified button as
+     * the trigger. The text of the button will be used as the triggertext.
+     */
+    public CollapsiblePanel (JButton trigger)
+    {
+        _trigger = trigger;
+        _text = trigger.getText();
+
+        VGroupLayout gl = new VGroupLayout(VGroupLayout.NONE);
+        gl.setOffAxisPolicy(VGroupLayout.STRETCH);
+        gl.setGap(0);
+        gl.setJustification(VGroupLayout.TOP);
+        gl.setOffAxisJustification(VGroupLayout.LEFT);
+        setLayout(gl);
+
+        _trigger.addActionListener(this);
+
+        // these are our only two components.
+        add(_trigger);
+        add(_content);
+
+        // and start us out showing
+        setCollapsed(false);
+    }
+
+    /**
+     * Construct a collapsible panel with the specified button text.
+     */
+    public CollapsiblePanel (String triggertext)
+    {
+        this(new JButton(triggertext));
+    }
+
+    /**
+     * Get the content panel for filling in with sweet content goodness.
+     */
+    public JPanel getContent ()
+    {
+        return _content;
+    }
+
+    // documentation from interface ActionListener
+    public void actionPerformed (ActionEvent e)
+    {
+        if (e.getSource() == _trigger) {
+            setCollapsed(!isCollapsed());
+        }
+    }
+
+    /**
+     * Is the panel collapsed?
+     */
+    public boolean isCollapsed ()
+    {
+        return !_content.isVisible();
+    }
+
+    /**
+     * Set the collapsion state.
+     */
+    public void setCollapsed (boolean collapse)
+    {
+        if (collapse) {
+            _content.hide();
+            _trigger.setText("+ " + _text);
+        } else {
+            _content.show();
+            _trigger.setText("- " + _text);
+        }
+    }
+
+    /** The button that triggers collapsion. */
+    protected JButton _trigger;
+
+    /** The original text in the button, oh this's gonna have to change. */
+    protected String _text;
+
+    /** The who in the what now? */
+    protected JPanel _content = new JPanel();
+}