Changeset 2759 in josm for trunk/src/org/openstreetmap/josm/gui/NavigatableComponent.java

Timestamp:

2010-01-07T19:29:53+01:00 (16 years ago)

Author:

mjulius

Message:

Make the new zoom previous and next actions listen to zoom changes and set enabled state.

File:

• trunk/src/org/openstreetmap/josm/gui/NavigatableComponent.java (modified) (4 diffs)

trunk/src/org/openstreetmap/josm/gui/NavigatableComponent.java

@@ -13 +13 @@
 import java.util.List;
 import java.util.TreeMap;
+import java.util.concurrent.CopyOnWriteArrayList;
 
 import javax.swing.JComponent;
@@ -38 +39 @@
  */
 public class NavigatableComponent extends JComponent implements Helpful {
+
+    /**
+     * Interface to notify listeners of the change of the zoom area.
+     */
+    public interface ZoomChangeListener {
+        void zoomChanged();
+    }
+
+    /**
+     * the zoom listeners
+     */
+    private static final CopyOnWriteArrayList<ZoomChangeListener> zoomChangeListeners = new CopyOnWriteArrayList<ZoomChangeListener>();
+
+    /**
+     * Removes a zoom change listener
+     *
+     * @param listener the listener. Ignored if null or already absent
+     */
+    public static void removeZoomChangeListener(NavigatableComponent.ZoomChangeListener listener) {
+        zoomChangeListeners.remove(listener);
+    }
+
+    /**
+     * Adds a zoom change listener
+     *
+     * @param listener the listener. Ignored if null or already registered.
+     */
+    public static void addZoomChangeListener(NavigatableComponent.ZoomChangeListener listener) {
+        if (listener != null) {
+            zoomChangeListeners.addIfAbsent(listener);
+        }
+    }
+
+    protected static void fireZoomChanged() {
+        for (ZoomChangeListener l : zoomChangeListeners) {
+            l.zoomChanged();
+        }
+    }
+
 
     public static final int snapDistance = Main.pref.getInteger("node.snap-distance", 10);
@@ -267 +307 @@
 
         repaint();
+        fireZoomChanged();
     }
 
@@ -367 +408 @@
             zoomNoUndoTo(zoom.getCenterEastNorth(), zoom.getScale());
         }
+    }
+
+    public boolean hasZoomUndoEntries() {
+        return !zoomUndoBuffer.isEmpty();
+    }
+
+    public boolean hasZoomRedoEntries() {
+        return !zoomRedoBuffer.isEmpty();
     }