Abstract ViewController, Implementations, Documentation.

src/snap/games/DevConsole.java

@@ -6,7 +6,7 @@
 /**
  * A class to provide developer controls to a GameController.
  */
-public class DevConsole extends ViewController {
+public class DevConsole extends DefaultViewController {
 
     // The GameController
     private GameController _gameController;

src/snap/games/GameController.java

@@ -7,7 +7,7 @@
 /**
  * The controller class for a GameView.
  */
-public class GameController extends ViewController {
+public class GameController extends DefaultViewController {
 
     // The frame rate
     private double _frameRate = 30;

src/snap/styler/FontPicker.java

@@ -8,7 +8,7 @@
 /**
  * A panel to help users pick a font by preview.
  */
-public class FontPicker extends ViewController {
+public class FontPicker extends DefaultViewController {
 
     // The DialogBox when running
     private DialogBox  _dbox;

src/snap/styler/StylerOwner.java

@@ -1,10 +1,11 @@
 package snap.styler;
+import snap.view.DefaultViewController;
 import snap.view.ViewController;
 
 /**
  * A simple subclass of view controller to work with a Styler.
  */
-public class StylerOwner extends ViewController {
+public class StylerOwner extends DefaultViewController {
 
     // The Styler
     private Styler _styler;

src/snap/util/ActivityMonitorPanel.java

@@ -88,7 +88,7 @@ protected void handleMonitorPropChange(PropChange propChange)
     /**
      * This view controller class shows UI for ActivityMonitorPanel.
      */
-    private class ActivityMonitorPanelViewOwner extends ViewController {
+    private class ActivityMonitorPanelViewOwner extends DefaultViewController {
 
         // The dialog box
         private DialogBox _dialogBox;

src/snap/view/DefaultViewController.java

@@ -0,0 +1,63 @@
+package snap.view;
+
+/**
+ * An implementation of ViewController that has all abstract methods implemented with a standard default. To use this
+ * class properly, the class methods must be overridden methods to use this class.
+ */
+public class DefaultViewController extends SimpleViewController {
+
+    /**
+     * Constructor.
+     */
+    public DefaultViewController()  {super();}
+
+    /**
+     * Constructor with given View for UI.
+     */
+    public DefaultViewController(View aView) {super(aView);}
+
+    /**
+     * Initializes the UI panel. This method provides the ability to alter any settings or components of the View that
+     * were not set by {@link #createUI()}.
+     * <br><br>
+     * This method is called automatically by SnapKit after the view has been initialized, and does not need to be
+     * called inside of an implementation.
+     * <br><br>
+     * Implementation note: It is not always necessary to implement this method, especially if the {@code createUI()}
+     * method was written by hand. It provides a way to add more initialization logic when the class has been loaded
+     * from a .snp file. By default, this method has no implementation.
+     */
+    @Override
+    protected void initUI() {
+
+    }
+
+    /**
+     * Called automatically by SnapKit after a user reacts with a UI component, this method allows the resetting of
+     * the UI. It will not cause accidental {@code respondUI(ViewEvent)} calls. It allows the user to reset or change
+     * aspects of the UI after an interaction, such as might be required for an animation or image draw.
+     * <br> <br>
+     * This method is overridable with no default implementation.
+     */
+    @Override
+    protected void resetUI() {
+
+    }
+
+    /**
+     * Called automatically by SnapKit when it detects a ViewEvent. This method should be overridden to respond to UI
+     * controls, and provide feedback to user interactions.
+     * <br>
+     * If you are coming from a Swing environment, this class serves the same purposes as the action listeners attached
+     * to each individual component. In this case, all of the events are funnelled into the same method, making it
+     * easier to keep track of interactions. Everything is managed from the same location.
+     * <br> <br>
+     * This method is overridable with no default implementation.
+     *
+     * @param anEvent
+     */
+    @Override
+    protected void respondUI(ViewEvent anEvent) {
+
+    }
+}

src/snap/view/SimpleViewController.java

@@ -0,0 +1,32 @@
+package snap.view;
+
+/**
+ * A simple implementation of ViewController that has most functionality already implemented. This implementation will
+ * load the UI from a .snp file named the same as this class, located in the resources dir of the jar package. The UI
+ * can be managed by implementing the {@link #initUI()} method, and referencing the names of components inside of that
+ * loaded View. To add events or feedback to elements of the UI, implement the {@link #respondUI(ViewEvent)} method and
+ * add your logic there.
+ * <br>
+ * All abstract methods of this class can be implemented or left empty depending on your needs.
+ */
+public abstract class SimpleViewController extends ViewController {
+
+    /**
+     * Constructor.
+     */
+    public SimpleViewController()  {super();}
+    /**
+     * Constructor with given View for UI.
+     */
+    public SimpleViewController(View aView) {super(aView);}
+
+    /**
+     * Creates the top level view for this controller by loading the UI from a .snp file in the 'resources' directory.
+     * The .snp file loaded must share the same name as this class.
+     * <br><br>
+     * This method is called automatically by SnapKit, and does not need to be called inside an implementation.
+     */
+    @Override
+    protected View createUI()  { return UILoader.loadViewForController(this); }
+
+}

src/snap/view/ViewController.java

@@ -8,9 +8,39 @@
 import snap.util.*;
 
 /**
- * A base controller class that manages a UI View (usually loaded from a snp UI file).
+ * A base controller class that manages a UI View.
+ * <br><br>
+ * A standard ViewController works around five simple methods:
+ * <ol>
+ *     <li>{@link #createUI()}</li>
+ *     <li>{@link #initUI()}</li>
+ *     <li>{@link #resetUI()}</li>
+ *     <li>{@link #respondUI(ViewEvent)}</li>
+ * </ol>
+ * <br>
+ * <b>createUI()</b><br>
+ * Called by SnapKit when the View is initialized, this method is responsible for the creation of the view, and all of
+ * its components. The view can be created by hand, or loaded from a .snp file through the use of
+ * {@link UILoader#loadViewForController(ViewController)}.
+ * <br><br>
+ * <b>initUI()</b><br>
+ * Similar to {@code createUI()}, this method is also called during initialization, after {@code createUI()} has been
+ * run. This method is responsible for any additional initialization that needs to take place after the view has been
+ * created, such as setting settings.
+ * <br><br>
+ * <b>resetUI()</b><br>
+ * resetUI() is called automatically by SnapKit whenever the user reacts with any UI component, but will not cause
+ * accidental {@code respondUI(ViewEvent)} calls. It allows the user to reset or change aspects of the UI after an
+ * interaction, such as might be required for an animation or image draw.
+ * <br><br>
+ * <b>respondUI(ViewEvent)</b><br>
+ * Called automatically by SnapKit whenever a ViewEvent/user event has been detected. Use this method to provide
+ * interactions and feedback to buttons and other user tools. In Swing, the listeners are attached to individual
+ * components, but in SnapKit all of the controls are provided in a single place, allowing pieces to be swapped in
+ * and out as necessary.
+ * <br><br>
  */
-public class ViewController extends PropObject {
+public abstract class ViewController extends PropObject {
 
     // The UI View
     private View  _ui;
@@ -124,14 +154,30 @@ public synchronized View getUI()
     public <T extends View> T getUI(Class <T> aClass)  { return aClass.cast(getUI()); }
 
     /**
-     * Creates the top level view for this controller.
+     * Creates the top level view for this controller.  
+     * <br><br>
+     * This method is called automatically by SnapKit at initialization, and does not need to be called inside an
+     * implementation.
+     * <br><br>
+     * Implementation Note: This is where all components and members of the view should be composed and initialized. 
+     * This can be done by hand, or through use of the {@link UILoader#loadViewForController(ViewController)} loader
+     * method.
+     * @see UILoader#loadViewForController(ViewController) 
      */
-    protected View createUI()  { return UILoader.loadViewForController(this); }
+    abstract protected View createUI();
 
     /**
-     * Initializes the UI panel.
+     * Initializes the UI panel. This method provides the ability to alter any settings or components of the View that
+     * were not set by {@link #createUI()}.
+     * <br><br>
+     * This method is called automatically by SnapKit after the view has been initialized, and does not need to be
+     * called inside of an implementation.
+     * <br><br>
+     * Implementation note: It is not always necessary to implement this method, especially if the {@code createUI()}
+     * method was written by hand. It provides a way to add more initialization logic when the class has been loaded
+     * from a .snp file.
      */
-    protected void initUI()  { }
+    abstract protected void initUI();
 
     /**
      * Returns the first focus UI view for when window/dialog is made visible.
@@ -468,14 +514,23 @@ public ToggleGroup getToggleGroup(String aName)
     }
 
     /**
-     * Reset UI controls.
+     * Called automatically by SnapKit after a user reacts with a UI component, this method allows the resetting of
+     * the UI. It will not cause accidental {@code respondUI(ViewEvent)} calls. It allows the user to reset or change
+     * aspects of the UI after an interaction, such as might be required for an animation or image draw.
+     * <br> <br>
+     * This method is overridable with no default implementation.
      */
-    protected void resetUI()  { }
+    abstract protected void resetUI();
 
     /**
-     * Respond to UI controls.
+     * Called automatically by SnapKit when it detects a ViewEvent. This method should be overridden to respond to UI
+     * controls, and provide feedback to user interactions.
+     * <br>
+     * If you are coming from a Swing environment, this class serves the same purposes as the action listeners attached
+     * to each individual component. In this case, all of the events are funnelled into the same method, making it
+     * easier to keep track of interactions. Everything is managed from the same location.
      */
-    protected void respondUI(ViewEvent anEvent)  { }
+    abstract protected void respondUI(ViewEvent anEvent);
 
     /**
      * Resets UI later.

src/snap/view/ViewOwner.java

@@ -2,7 +2,12 @@
 
 /**
  * Temporary support for legacy ViewOwner.
+ * @deprecated see {@link ViewController} for the new naming, or {@link DefaultViewController} for the new
+ * implementation.
+ * @see ViewController
+ * @see DefaultViewController
  */
-public class ViewOwner extends ViewController {
+@Deprecated(since="2026.03")
+public class ViewOwner extends DefaultViewController {
 
 }

src/snap/view/ViewUpdater.java

@@ -411,7 +411,7 @@ public static void setShowFrameRate(boolean aValue)
             _frameRateLabel.setMargin(10, 10, 10, 20);
             _frameRateLabel.setPrefSize(100, 32);
             _frameRateLabel.setFont(new Font("Arial", 24));
-            ViewController frameRateOwner = new ViewController(_frameRateLabel);
+            ViewController frameRateOwner = new DefaultViewController(_frameRateLabel);
             frameRateOwner.getWindow().setType(WindowView.Type.UTILITY);
             frameRateOwner.getWindow().setAlwaysOnTop(true);
             frameRateOwner.setWindowVisible(true);

src/snap/viewx/ColorPanel.java

@@ -12,7 +12,7 @@
 /**
  * This class provides UI for selecting a color.
  */
-public class ColorPanel extends ViewController {
+public class ColorPanel extends DefaultViewController {
 
     // The currently selected color
     private Color _color = Color.BLACK;

src/snap/viewx/DefaultConsole.java

@@ -9,7 +9,7 @@
 /**
  * This class is a real implementation of Console.
  */
-public class DefaultConsole extends ViewController implements Console {
+public class DefaultConsole extends DefaultViewController implements Console {
 
     // The Console view
     private ColView _consoleView;

src/snap/viewx/DevPane.java

@@ -12,7 +12,7 @@
 /**
  * A view to allow inspection of View hierarchy.
  */
-public class DevPane extends ViewController {
+public class DevPane extends DefaultViewController {
 
     // The RootView
     private RootView  _rootView;

src/snap/viewx/DevPaneConsole.java

@@ -6,16 +6,14 @@
 import snap.text.TextStyle;
 import snap.util.Convert;
 import snap.util.KeyChain;
-import snap.view.BoxView;
-import snap.view.ScrollView;
-import snap.view.View;
-import snap.view.ViewController;
+import snap.view.*;
+
 import java.io.PrintStream;
 
 /**
  * A DevPane to show the console.
  */
-public class DevPaneConsole extends ViewController {
+public class DevPaneConsole extends DefaultViewController {
 
     // The ConsoleView
     private static ConsoleTextArea _consoleTextArea;

src/snap/viewx/DevPaneExceptions.java

@@ -7,7 +7,7 @@
 /**
  * A DevPane to show the console.
  */
-public class DevPaneExceptions extends ViewController {
+public class DevPaneExceptions extends DefaultViewController {
 
     // The selected index
     private int _selIndex = -1;

src/snap/viewx/DevPaneFiles.java

@@ -10,7 +10,7 @@
 /**
  * A DevPane tab for inspecting Graphics.
  */
-public class DevPaneFiles extends ViewController {
+public class DevPaneFiles extends DefaultViewController {
 
     // The root URL string
     private String _rootUrlString;

src/snap/viewx/DevPaneGraphics.java

@@ -6,7 +6,7 @@
 /**
  * A DevPane tab for inspecting Graphics.
  */
-public class DevPaneGraphics extends ViewController {
+public class DevPaneGraphics extends DefaultViewController {
 
     // The DevPane
     private DevPane  _devPane;

src/snap/viewx/DevPaneViewOwners.java

@@ -17,7 +17,7 @@
 /**
  * A DevPane tab for inspecting the view tree.
  */
-public class DevPaneViewOwners extends ViewController {
+public class DevPaneViewOwners extends DefaultViewController {
 
     // The DevPane
     private DevPane  _devPane;

src/snap/viewx/DevPaneViews.java

@@ -16,7 +16,7 @@
 /**
  * A DevPane tab for inspecting the view tree.
  */
-public class DevPaneViews extends ViewController {
+public class DevPaneViews extends DefaultViewController {
 
     // The DevPane
     private DevPane  _devPane;

src/snap/viewx/ExceptionReporter.java

@@ -16,7 +16,7 @@
  *   er.setInfo("MyApp Version X, Build Date: " + MyUtils.getBuildDate());
  *   Thread.setDefaultUncaughtExceptionHandler(er);
  */
-public class ExceptionReporter extends ViewController implements Thread.UncaughtExceptionHandler {
+public class ExceptionReporter extends DefaultViewController implements Thread.UncaughtExceptionHandler {
 
     // Backtrace text
     private String _backtraceText;

src/snap/viewx/FilePanel.java

@@ -17,7 +17,7 @@
 /**
  * A class to select a file to open or save.
  */
-public class FilePanel extends ViewController {
+public class FilePanel extends DefaultViewController {
 
     // Whether choosing file for save
     private boolean  _saving;

src/snap/viewx/FormBuilder.java

@@ -11,7 +11,7 @@
 /**
  * A class to build a form.
  */
-public class FormBuilder extends ViewController {
+public class FormBuilder extends DefaultViewController {
 
     // The root pane
     protected ColView  _formView;