3 files changed, 90 insertions, 1 deletions

diff --git a/core/java/android/app/MediaRouteActionProvider.java b/core/java/android/app/MediaRouteActionProvider.java
index b1fc90a..c2f5ac1 100644
--- a/core/java/android/app/MediaRouteActionProvider.java
+++ b/core/java/android/app/MediaRouteActionProvider.java
@@ -21,11 +21,14 @@ import com.android.internal.app.MediaRouteChooserDialogFragment;
 import android.content.Context;
 import android.content.ContextWrapper;
 import android.media.MediaRouter;
+import android.media.MediaRouter.RouteInfo;
 import android.util.Log;
 import android.view.ActionProvider;
 import android.view.MenuItem;
 import android.view.View;
 
+import java.lang.ref.WeakReference;
+
 public class MediaRouteActionProvider extends ActionProvider {
     private static final String TAG = "MediaRouteActionProvider";
 
@@ -35,11 +38,13 @@ public class MediaRouteActionProvider extends ActionProvider {
     private MediaRouteButton mView;
     private int mRouteTypes;
     private View.OnClickListener mExtendedSettingsListener;
+    private RouterCallback mCallback;
 
     public MediaRouteActionProvider(Context context) {
         super(context);
         mContext = context;
         mRouter = (MediaRouter) context.getSystemService(Context.MEDIA_ROUTER_SERVICE);
+        mCallback = new RouterCallback(this);
 
         // Start with live audio by default.
         // TODO Update this when new route types are added; segment by API level
@@ -48,7 +53,14 @@ public class MediaRouteActionProvider extends ActionProvider {
     }
 
     public void setRouteTypes(int types) {
+        if (mRouteTypes == types) return;
+        if (mRouteTypes != 0) {
+            mRouter.removeCallback(mCallback);
+        }
         mRouteTypes = types;
+        if (types != 0) {
+            mRouter.addCallback(types, mCallback);
+        }
         if (mView != null) {
             mView.setRouteTypes(mRouteTypes);
         }
@@ -68,7 +80,6 @@ public class MediaRouteActionProvider extends ActionProvider {
         }
         mMenuItem = item;
         mView = new MediaRouteButton(mContext);
-        mMenuItem.setVisible(mRouter.getRouteCount() > 1);
         mView.setRouteTypes(mRouteTypes);
         mView.setExtendedSettingsClickListener(mExtendedSettingsListener);
         return mView;
@@ -123,4 +134,34 @@ public class MediaRouteActionProvider extends ActionProvider {
     public boolean isVisible() {
         return mRouter.getRouteCount() > 1;
     }
+
+    private static class RouterCallback extends MediaRouter.SimpleCallback {
+        private WeakReference<MediaRouteActionProvider> mAp;
+
+        RouterCallback(MediaRouteActionProvider ap) {
+            mAp = new WeakReference<MediaRouteActionProvider>(ap);
+        }
+
+        @Override
+        public void onRouteAdded(MediaRouter router, RouteInfo info) {
+            final MediaRouteActionProvider ap = mAp.get();
+            if (ap == null) {
+                router.removeCallback(this);
+                return;
+            }
+
+            ap.refreshVisibility();
+        }
+
+        @Override
+        public void onRouteRemoved(MediaRouter router, RouteInfo info) {
+            final MediaRouteActionProvider ap = mAp.get();
+            if (ap == null) {
+                router.removeCallback(this);
+                return;
+            }
+
+            ap.refreshVisibility();
+        }
+    }
 }
diff --git a/core/java/android/view/ActionProvider.java b/core/java/android/view/ActionProvider.java
index af9bf9e..c3aafde 100644
--- a/core/java/android/view/ActionProvider.java
+++ b/core/java/android/view/ActionProvider.java
@@ -17,6 +17,7 @@
 package android.view;
 
 import android.content.Context;
+import android.util.Log;
 
 /**
  * An ActionProvider defines rich menu interaction in a single component.
@@ -55,7 +56,9 @@ import android.content.Context;
  * @see MenuItem#getActionProvider()
  */
 public abstract class ActionProvider {
+    private static final String TAG = "ActionProvider";
     private SubUiVisibilityListener mSubUiVisibilityListener;
+    private VisibilityListener mVisibilityListener;
 
     /**
      * Creates a new instance. ActionProvider classes should always implement a
@@ -122,6 +125,18 @@ public abstract class ActionProvider {
     }
 
     /**
+     * If this ActionProvider is associated with an item in a menu,
+     * refresh the visibility of the item based on {@link #overridesItemVisibility()} and
+     * {@link #isVisible()}. If {@link #overridesItemVisibility()} returns false, this call
+     * will have no effect.
+     */
+    public void refreshVisibility() {
+        if (mVisibilityListener != null && overridesItemVisibility()) {
+            mVisibilityListener.onActionProviderVisibilityChanged(isVisible());
+        }
+    }
+
+    /**
      * Performs an optional default action.
      * <p>
      * For the case of an action provider placed in a menu item not shown as an action this
@@ -207,9 +222,34 @@ public abstract class ActionProvider {
     }
 
     /**
+     * Set a listener to be notified when this ActionProvider's overridden visibility changes.
+     * This should only be used by MenuItem implementations.
+     *
+     * @param listener listener to set
+     */
+    public void setVisibilityListener(VisibilityListener listener) {
+        if (mVisibilityListener != null) {
+            Log.w(TAG, "setVisibilityListener: Setting a new ActionProvider.VisibilityListener " +
+                    "when one is already set. Are you reusing this " + getClass().getSimpleName() +
+                    " instance while it is still in use somewhere else?");
+        }
+        mVisibilityListener = listener;
+    }
+
+    /**
      * @hide Internal use only
      */
     public interface SubUiVisibilityListener {
         public void onSubUiVisibilityChanged(boolean isVisible);
     }
+
+    /**
+     * Listens to changes in visibility as reported by {@link ActionProvider#refreshVisibility()}.
+     *
+     * @see ActionProvider#overridesItemVisibility()
+     * @see ActionProvider#isVisible()
+     */
+    public interface VisibilityListener {
+        public void onActionProviderVisibilityChanged(boolean isVisible);
+    }
 }
diff --git a/core/java/com/android/internal/view/menu/MenuItemImpl.java b/core/java/com/android/internal/view/menu/MenuItemImpl.java
index 9baface..9f7441d 100644
--- a/core/java/com/android/internal/view/menu/MenuItemImpl.java
+++ b/core/java/com/android/internal/view/menu/MenuItemImpl.java
@@ -589,9 +589,17 @@ public final class MenuItemImpl implements MenuItem {
     }
 
     public MenuItem setActionProvider(ActionProvider actionProvider) {
+        if (mActionProvider != null) {
+            mActionProvider.setVisibilityListener(null);
+        }
         mActionView = null;
         mActionProvider = actionProvider;
         mMenu.onItemsChanged(true); // Measurement can be changed
+        mActionProvider.setVisibilityListener(new ActionProvider.VisibilityListener() {
+            @Override public void onActionProviderVisibilityChanged(boolean isVisible) {
+                mMenu.onItemVisibleChanged(MenuItemImpl.this);
+            }
+        });
         return this;
     }