1 files changed, 68 insertions, 6 deletions

diff --git a/src/com/android/tv/ui/sidepanel/Item.java b/src/com/android/tv/ui/sidepanel/Item.java
index 53238fd7..da9b39b0 100644
--- a/src/com/android/tv/ui/sidepanel/Item.java
+++ b/src/com/android/tv/ui/sidepanel/Item.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2014 The Android Open Source Project
+ * Copyright (C) 2015 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,11 +17,73 @@
 package com.android.tv.ui.sidepanel;
 
 import android.view.View;
+import android.view.ViewGroup;
 
 public abstract class Item {
+    private View mItemView;
+    private boolean mEnabled = true;
+
+    public void setEnabled(boolean enabled) {
+        if (mEnabled != enabled) {
+            mEnabled = enabled;
+            if (mItemView != null) {
+                setEnabledInternal(mItemView, enabled);
+            }
+        }
+    }
+
+    /**
+     * Returns whether this item is enabled.
+     */
+    public boolean isEnabled() {
+        return mEnabled;
+    }
+
+    public final void notifyUpdated() {
+        if (mItemView != null) {
+            onUpdate();
+        }
+    }
+
     protected abstract int getResourceId();
-    protected void bind(@SuppressWarnings("unused") View view) { }
-    protected void unbind() { }
-    protected void onSelected() { }
-    protected void onFocused() { }
-}
\ No newline at end of file
+
+    protected void onBind(View view) {
+        mItemView = view;
+    }
+
+    protected void onUnbind() {
+        mItemView = null;
+    }
+
+    /**
+     * Called after onBind is called and when {@link #notifyUpdated} is called.
+     * {@link #notifyUpdated} is usually called by {@link SideFragment#notifyItemChanged} and
+     * {@link SideFragment#notifyItemsChanged}.
+     */
+    protected void onUpdate() {
+        setEnabledInternal(mItemView, mEnabled);
+    }
+
+    protected abstract void onSelected();
+
+    protected void onFocused() {
+    }
+
+    /**
+     * Returns true if the item is bound, i.e., onBind is called.
+     */
+    protected boolean isBound() {
+        return mItemView != null;
+    }
+
+    private void setEnabledInternal(View view, boolean enabled) {
+        view.setEnabled(enabled);
+        if (view instanceof ViewGroup) {
+            ViewGroup parent = (ViewGroup) view;
+            int childCount = parent.getChildCount();
+            for (int i = 0; i < childCount; ++i) {
+                setEnabledInternal(parent.getChildAt(i), enabled);
+            }
+        }
+    }
+}