Created a base class for panels that work with controllers. Enhanced

controller to automatically call wasShown/wasHidden when its associated
panel is added to and removed from the component hierarchy.


git-svn-id: https://samskivert.googlecode.com/svn/trunk@659 6335cc39-0255-0410-8fd6-9bcaacd3b74c

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

@@ -0,0 +1,49 @@
+//
+// $Id: ControlledPanel.java,v 1.1 2002/03/16 20:52:07 mdb Exp $
+
+package com.samskivert.swing;
+
+import javax.swing.JPanel;
+
+/**
+ * A controlled panel takes care of setting up its controller and
+ * providing it. When operating in conjunction with a controlled panel,
+ * the controller can automatically invoke {@link Controller#wasAdded} and
+ * {@link Controller#wasRemoved}.
+ */
+public abstract class ControlledPanel extends JPanel
+    implements ControllerProvider
+{
+    /**
+     * Creates a controlled panel and its associated controller.
+     */
+    public ControlledPanel ()
+    {
+        _controller = createController();
+
+        // let the controller know about this panel
+        _controller.setControlledPanel(this);
+    }
+
+    // documentation inherited from interface
+    public Controller getController ()
+    {
+        return _controller;
+    }
+
+    /**
+     * Called to create the controller associated with this controlled
+     * panel. Derived classes should override this and instantiate the
+     * appropriate controller derived class. Note that this will be called
+     * very early in the construction process, before derived classes have
+     * access to their member data and as such, the derived panel will not
+     * be able to pass anything interesting to its associated controller
+     * constructor. The expectation is that it will obtain a reference to
+     * its controller later in its own constructor and supply any extra
+     * initialization data that is needed at that time.
+     */
+    protected abstract Controller createController ();
+
+    /** The controller with which we are working. */
+    protected Controller _controller;
+}

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

@@ -1,5 +1,5 @@
 //
-// $Id: Controller.java,v 1.9 2002/02/28 21:55:14 mdb Exp $
+// $Id: Controller.java,v 1.10 2002/03/16 20:52:07 mdb Exp $
 //
 // samskivert library - useful routines for java programs
 // Copyright (C) 2001 Michael Bayne
@@ -25,7 +25,11 @@ import java.awt.EventQueue;
 import java.awt.event.ActionEvent;
 import java.awt.event.ActionListener;
 
+import javax.swing.JPanel;
+import javax.swing.event.AncestorEvent;
+
 import com.samskivert.Log;
+import com.samskivert.swing.event.AncestorAdapter;
 import com.samskivert.swing.event.CommandEvent;
 
 /**
@@ -86,6 +90,43 @@ public abstract class Controller
         }
     };
 
+    /**
+     * Lets this controller know about the panel that it is controlling.
+     */
+    public void setControlledPanel (JPanel panel)
+    {
+        panel.addAncestorListener(new AncestorAdapter() {
+            public void ancestorAdded (AncestorEvent event) {
+                wasAdded();
+            }
+            public void ancestorRemoved (AncestorEvent event) {
+                wasRemoved();
+            }
+        });
+    }
+
+    /**
+     * Called when the panel controlled by this controller was added to
+     * the user interface hierarchy. This assumes that the controlled
+     * panel made itself known to the controller via {@link
+     * #setControlledPanel} (which is done automatically by {@link
+     * ControlledPanel} and derived classes).
+     */
+    public void wasAdded ()
+    {
+    }
+
+    /**
+     * Called when the panel controlled by this controller was removed
+     * from the user interface hierarchy. This assumes that the controlled
+     * panel made itself known to the controller via {@link
+     * #setControlledPanel} (which is done automatically by {@link
+     * ControlledPanel} and derived classes).
+     */
+    public void wasRemoved ()
+    {
+    }
+
     /**
      * Instructs this controller to process this action event. When an
      * action is posted by a user interface element, it will be posted to