Closes #587

protege-editor-core/src/main/java/org/protege/editor/core/ui/view/CloseIcon.java

@@ -0,0 +1,41 @@
+package org.protege.editor.core.ui.view;
+
+import javax.annotation.Nonnull;
+import java.awt.*;
+
+/**
+ * Matthew Horridge
+ * Stanford Center for Biomedical Informatics Research
+ * 28 Nov 2016
+ */
+public class CloseIcon extends ViewBarIcon {
+
+    private static final BasicStroke STROKE = new BasicStroke(2f);
+
+    private static final CloseIcon ICON = new CloseIcon();
+
+    private CloseIcon() {
+    }
+
+    /**
+     * Gets the Close View icon.
+     * @return The Close View icon.
+     */
+    @Nonnull
+    public static CloseIcon get() {
+        return ICON;
+    }
+
+    @Override
+    public void paintIcon(Component c, Graphics g, int x, int y) {
+        Graphics2D g2 = (Graphics2D) g.create();
+        g2.setColor(Color.WHITE);
+        int width = getIconWidth();
+        int height = getIconHeight();
+        g2.drawRect(1, 1, width - 2, height - 2);
+        g2.setStroke(STROKE);
+        g2.drawLine(4, 4, width - 4, height - 4);
+        g2.drawLine(4, height - 4, width - 4, 4);
+    }
+
+}

protege-editor-core/src/main/java/org/protege/editor/core/ui/view/FloatIcon.java

@@ -0,0 +1,36 @@
+package org.protege.editor.core.ui.view;
+
+import javax.annotation.Nonnull;
+import java.awt.*;
+
+/**
+ * Matthew Horridge
+ * Stanford Center for Biomedical Informatics Research
+ * 28 Nov 2016
+ */
+public class FloatIcon extends ViewBarIcon {
+
+    public static final FloatIcon ICON = new FloatIcon();
+
+    private FloatIcon() {
+    }
+
+    /**
+     * Gets the Float View Icon.
+     * @return The Float View Icon.
+     */
+    @Nonnull
+    public static FloatIcon get() {
+        return ICON;
+    }
+
+    @Override
+    public void paintIcon(Component c, Graphics g, int x, int y) {
+        Graphics2D g2 = (Graphics2D) g.create();
+        g2.setColor(Color.WHITE);
+        int width = getIconWidth();
+        int height = getIconHeight();
+        g2.drawRect(1, 1, width - 2, height - 2);
+        g2.fillRect(3, 3, width - 6, height - 6);
+    }
+}

protege-editor-core/src/main/java/org/protege/editor/core/ui/view/HelpIcon.java

@@ -0,0 +1,56 @@
+package org.protege.editor.core.ui.view;
+
+import javax.swing.*;
+import java.awt.*;
+import java.awt.geom.Rectangle2D;
+
+import static java.awt.RenderingHints.KEY_ANTIALIASING;
+import static java.awt.RenderingHints.VALUE_ANTIALIAS_ON;
+
+/**
+ * Matthew Horridge
+ * Stanford Center for Biomedical Informatics Research
+ * 28 Nov 2016
+ */
+public class HelpIcon extends ViewBarIcon {
+
+
+    private static final String HELP_STRING = "?";
+
+    private static final HelpIcon ICON = new HelpIcon();
+
+    private final Font font;
+
+    public HelpIcon() {
+        this.font = new Font("Verdana", Font.BOLD, 9);
+    }
+
+    public static HelpIcon get() {
+        return ICON;
+    }
+
+
+    @Override
+    public void paintIcon(Component c, Graphics graphics, int x, int y) {
+        Graphics2D g2 = (Graphics2D) graphics.create();
+        g2.setColor(Color.WHITE);
+        int width = getIconWidth();
+        int height = getIconHeight();
+        g2.drawRect(1, 1, width - 2, height - 2);
+
+        g2.setFont(font);
+        g2.setRenderingHint(KEY_ANTIALIASING, VALUE_ANTIALIAS_ON);
+
+        FontMetrics fm = g2.getFontMetrics();
+        Rectangle2D bounds = fm.getStringBounds(HELP_STRING, g2);
+
+        float xPos = (float) ((width - bounds.getWidth()) / 2);
+        int ascent = fm.getAscent();
+        int descent = fm.getDescent();
+        float yPos = ((height + 1) / 2 - (ascent + descent) / 2 + ascent - 1);
+        g2.drawString(HELP_STRING,
+                     xPos,
+                     yPos);
+        g2.translate(-x, -y);
+    }
+}

protege-editor-core/src/main/java/org/protege/editor/core/ui/view/HorizontalMoreIcon.java

@@ -0,0 +1,45 @@
+package org.protege.editor.core.ui.view;
+
+import javax.swing.*;
+import java.awt.*;
+
+import static java.awt.Color.WHITE;
+import static java.awt.RenderingHints.KEY_ANTIALIASING;
+import static java.awt.RenderingHints.VALUE_ANTIALIAS_ON;
+
+/**
+ * Matthew Horridge
+ * Stanford Center for Biomedical Informatics Research
+ * 28 Nov 2016
+ */
+public class HorizontalMoreIcon implements Icon {
+
+    public static final int DOT_SIZE = 4;
+
+    private final int WIDTH = 18;
+
+    private final int HEIGHT = 8;
+
+    @Override
+    public void paintIcon(Component c, Graphics g, int x, int y) {
+        Graphics2D g2 = (Graphics2D) g.create();
+        g2.setRenderingHint(KEY_ANTIALIASING, VALUE_ANTIALIAS_ON);
+        g2.setColor(WHITE);
+        g2.translate(0, HEIGHT / 2 - DOT_SIZE / 2);
+        g2.fillOval(0, 0, DOT_SIZE, DOT_SIZE);
+        g2.translate(5, 0);
+        g2.fillOval(0, 0, DOT_SIZE, DOT_SIZE);
+        g2.translate(5, 0);
+        g2.fillOval(0, 0, DOT_SIZE, DOT_SIZE);
+    }
+
+    @Override
+    public int getIconWidth() {
+        return WIDTH;
+    }
+
+    @Override
+    public int getIconHeight() {
+        return HEIGHT;
+    }
+}

protege-editor-core/src/main/java/org/protege/editor/core/ui/view/SplitHorizontallyIcon.java

@@ -0,0 +1,38 @@
+package org.protege.editor.core.ui.view;
+
+import javax.annotation.Nonnull;
+import java.awt.*;
+
+/**
+ * Matthew Horridge
+ * Stanford Center for Biomedical Informatics Research
+ * 28 Nov 2016
+ */
+public class SplitHorizontallyIcon extends ViewBarIcon {
+
+    private static final SplitHorizontallyIcon ICON = new SplitHorizontallyIcon();
+
+    private SplitHorizontallyIcon() {
+    }
+
+    /**
+     * Gets the Split Horizontall Icon.
+     * @return The Split Horizontally Icon.
+     */
+    @Nonnull
+    public static SplitHorizontallyIcon get() {
+        return ICON;
+    }
+
+    @Override
+    public void paintIcon(Component c, Graphics g, int x, int y) {
+        Graphics2D g2 = (Graphics2D) g.create();
+        g2.setColor(Color.WHITE);
+        int width = getIconWidth();
+        int height = getIconHeight();
+        g2.drawRect(1, 1, width - 2, height - 2);
+        g2.drawLine(1, height / 2 - 1, width - 1, height / 2 - 1);
+        g2.drawLine(1, height / 2    , width - 1, height / 2    );
+        g2.drawLine(1, height / 2 + 1, width - 1, height / 2 + 1);
+    }
+}

protege-editor-core/src/main/java/org/protege/editor/core/ui/view/SplitVerticallyIcon.java

@@ -0,0 +1,40 @@
+package org.protege.editor.core.ui.view;
+
+import javax.annotation.Nonnull;
+import java.awt.*;
+
+/**
+ * Matthew Horridge
+ * Stanford Center for Biomedical Informatics Research
+ * 28 Nov 2016
+ */
+public class SplitVerticallyIcon extends ViewBarIcon {
+
+    private static final SplitVerticallyIcon ICON = new SplitVerticallyIcon();
+
+    private SplitVerticallyIcon() {
+    }
+
+    /**
+     * Gets the Split Vertically Icon.
+     * @return The Split Vertically Icon.
+     */
+    @Nonnull
+    public static SplitVerticallyIcon get() {
+        return ICON;
+    }
+
+    @Override
+    public void paintIcon(Component c, Graphics g, int x, int y) {
+        Graphics2D g2 = (Graphics2D) g.create();
+        g2.setColor(Color.WHITE);
+        int width = getIconWidth();
+        int height = getIconHeight();
+        g2.drawRect(1, 1, width - 2, height - 2);
+        g2.drawLine(width / 2 - 1, 1, width / 2 - 1, height - 1);
+        g2.drawLine(width / 2, 1, width / 2, height - 1);
+        g2.drawLine(width / 2 + 1, 1, width / 2 + 1, height - 1);
+    }
+
+
+}

protege-editor-core/src/main/java/org/protege/editor/core/ui/view/View.java

@@ -21,6 +21,7 @@
 import javax.swing.*;
 import java.awt.*;
 import java.awt.event.*;
+import java.io.IOException;
 import java.util.*;
 
 
@@ -335,40 +336,14 @@ public String getGroupIndex() {
 
     private void addViewManipulationActions() {
         // View manipulation toolbar
-        viewBarComponent.getViewBar().getViewBanner().addAction(new AbstractAction("Split vertically",
-                                                                                   Icons.getIcon(
-                                                                                           SPLIT_VERTICALLY_ICON_NAME)) {
-
-            public void actionPerformed(ActionEvent e) {
-                splitVertically();
-            }
-        });
-        viewBarComponent.getViewBar().getViewBanner().addAction(new AbstractAction("Split horizontally",
-                                                                                   Icons.getIcon(
-                                                                                           SPLIT_HORIZONTALLY_ICON_NAME)) {
-
-
-            public void actionPerformed(ActionEvent e) {
-                splitHorizontally();
-            }
-        });
-        viewBarComponent.getViewBar().getViewBanner().addAction(new AbstractAction("Float",
-                                                                                   Icons.getIcon(FLOAT_ICON_NAME)) {
-
-            public void actionPerformed(ActionEvent e) {
-                copyAndFloatView();
-            }
-        });
-        viewBarComponent.getViewBar().getViewBanner().addAction(new AbstractAction("Close",
-                                                                                   Icons.getIcon(CLOSE_ICON_NAME)) {
-
-            public void actionPerformed(ActionEvent e) {
-                closeView();
-            }
-        });
+        ViewBanner viewBanner = viewBarComponent.getViewBar().getViewBanner();
+        plugin.getHelpLink().ifPresent(u -> viewBanner.addAction("Help", HelpIcon.get(), this::showHelpIfPresent));
+        viewBanner.addAction("Split vertically", SplitVerticallyIcon.get(), this::splitVertically);
+        viewBanner.addAction("Split horizontally", SplitHorizontallyIcon.get(), this::splitHorizontally);
+        viewBanner.addAction("Float", FloatIcon.get(), this::copyAndFloatView);
+        viewBanner.addAction("Close", CloseIcon.get(), this::closeView);
     }
 
-
     private NodePanel getNodePanel() {
         return (NodePanel) SwingUtilities.getAncestorOfClass(NodePanel.class, this);
     }
@@ -417,6 +392,18 @@ else if (getParent() instanceof ViewContainer) {
         }
     }
 
+    private void showHelpIfPresent() {
+        plugin.getHelpLink().ifPresent(l -> {
+            try {
+                Desktop.getDesktop().browse(l);
+            } catch (IOException e1) {
+                logger.warn("An error occurred whilst navigating to the help for the {} view.  URL: {}",
+                            plugin.getLabel(),
+                            l);
+            }
+        });
+    }
+
 
     private void createContent() {
         try {

protege-editor-core/src/main/java/org/protege/editor/core/ui/view/ViewBanner.java

@@ -2,8 +2,10 @@
 
 import org.protege.editor.core.ui.view.button.ViewButtonUI;
 
+import javax.annotation.Nonnull;
 import javax.swing.*;
 import java.awt.*;
+import java.awt.event.ActionEvent;
 import java.beans.PropertyChangeEvent;
 import java.beans.PropertyChangeListener;
 import java.util.ArrayList;
@@ -123,23 +125,33 @@ public void removeAllActions() {
         toolBar.removeAll();
     }
 
+    /**
+     * Adds an action to the view header.
+     * @param name The name of the action.
+     * @param icon An icon to display in the view header for the action.
+     * @param runnable The code that should be called when the action is executed.
+     */
+    public void addAction(@Nonnull String name,
+                          @Nonnull Icon icon,
+                          @Nonnull final Runnable runnable) {
+        addAction(new AbstractAction(name, icon) {
+            @Override
+            public void actionPerformed(ActionEvent e) {
+                runnable.run();
+            }
+        });
+    }
 
     /**
      * Adds an action to the view header.
      * @param action The action to be added.
      */
-    public void addAction(Action action) {
+    public void addAction(@Nonnull Action action) {
         String name = (String) action.getValue(Action.NAME);
         action.putValue(Action.NAME, "");
         action.putValue(Action.SHORT_DESCRIPTION, name);
         JButton button = new JButton(action) {
-            /**
-             * 
-             */
-            private static final long serialVersionUID = -5577350824168578334L;
-
             public void updateUI() {
-//                super.updateUI();
             }
         };
         button.setFocusable(false);