Send events when the mouse cursor enters a controlled component.

diff --git a/src/main/java/net/pterodactylus/sonitus/gui/PipelinePanel.java b/src/main/java/net/pterodactylus/sonitus/gui/PipelinePanel.java
index ab1c484..dcb3e3f 100644 (file)
--- a/src/main/java/net/pterodactylus/sonitus/gui/PipelinePanel.java
+++ b/src/main/java/net/pterodactylus/sonitus/gui/PipelinePanel.java
@@ -22,10 +22,14 @@ import static javax.swing.BorderFactory.createEtchedBorder;
 import java.awt.GridBagConstraints;
 import java.awt.GridBagLayout;
 import java.awt.Insets;
+import java.awt.event.MouseAdapter;
+import java.awt.event.MouseEvent;
 import java.util.Collection;
+import java.util.EventListener;
 import java.util.List;
 import javax.swing.JLabel;
 import javax.swing.JPanel;
+import javax.swing.event.EventListenerList;
 
 import net.pterodactylus.sonitus.data.Controlled;
 import net.pterodactylus.sonitus.data.Filter;
@@ -45,6 +49,9 @@ public class PipelinePanel extends JPanel {
        /** The pipeline being displayed. */
        private final Pipeline pipeline;
 
+       /** The component hover listeners. */
+       private final EventListenerList componentHoverListeners = new EventListenerList();
+
        /**
         * Creates a new pipeline panel displaying the given pipeline.
         *
@@ -58,6 +65,20 @@ public class PipelinePanel extends JPanel {
        }
 
        //
+       // LISTENER MANAGEMENT
+       //
+
+       /**
+        * Adds the given component hover listener to this panel.
+        *
+        * @param componentHoverListener
+        *              The component hover listener to add
+        */
+       public void addComponentHoverListener(ComponentHoverListener componentHoverListener) {
+               componentHoverListeners.add(ComponentHoverListener.class, componentHoverListener);
+       }
+
+       //
        // PRIVATE METHODS
        //
 
@@ -103,10 +124,19 @@ public class PipelinePanel extends JPanel {
         * @param width
         *              The width of the component in grid cells
         */
-       private void addControlled(Controlled controlled, int level, int position, int width) {
+       private void addControlled(final Controlled controlled, int level, int position, int width) {
                /* create a GUI component that displays the component. */
                JLabel sourceLabel = new JLabel(controlled.name());
                sourceLabel.setBorder(createEtchedBorder());
+               sourceLabel.addMouseListener(new MouseAdapter() {
+
+                       @Override
+                       public void mouseEntered(MouseEvent mouseEvent) {
+                               for (ComponentHoverListener componentHoverListener : componentHoverListeners.getListeners(ComponentHoverListener.class)) {
+                                       componentHoverListener.componentEntered(controlled);
+                               }
+                       }
+               });
 
                /* show component. */
                add(sourceLabel, new GridBagConstraints(position, level, width, 1, 1.0, 1.0, GridBagConstraints.CENTER, GridBagConstraints.BOTH, new Insets(0, 0, 0, 0), 0, 0));
@@ -127,4 +157,23 @@ public class PipelinePanel extends JPanel {
                }
        }
 
+       /**
+        * Interface for objects that want to be notified if the user moves the mouse
+        * cursor over a controlled component.
+        *
+        * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+        */
+       public static interface ComponentHoverListener extends EventListener {
+
+               /**
+                * Notifies the listener that the mouse is now over the given controlled
+                * component.
+                *
+                * @param controlled
+                *              The controlled component now under the mouse
+                */
+               void componentEntered(Controlled controlled);
+
+       }
+
 }