Fix most of issue #2271640: Fix wallpaper etc docs

Only thing remaining is the live wallpaper feature.

Change-Id: I8854c7978999d759bf618307f4f984c9c89d3fc8

2 files changed, 13 insertions, 1 deletions

diff --git a/core/java/android/service/wallpaper/WallpaperService.java b/core/java/android/service/wallpaper/WallpaperService.java
index b29d837..8000ad3 100644
--- a/core/java/android/service/wallpaper/WallpaperService.java
+++ b/core/java/android/service/wallpaper/WallpaperService.java
@@ -46,7 +46,12 @@ import android.view.WindowManagerImpl;
 
 /**
  * A wallpaper service is responsible for showing a live wallpaper behind
- * applications that would like to sit on top of it.
+ * applications that would like to sit on top of it.  This service object
+ * itself does very little -- its only purpose is to generate instances of
+ * {@link WallpaperSerice.Engine} as needed.  Implementing a wallpaper thus
+ * involves subclassing from this, subclassing an Engine implementation,
+ * and implementing {@link #onCreateEngine()} to return a new instance of
+ * your engine.
  */
 public abstract class WallpaperService extends Service {
     /**
@@ -861,5 +866,11 @@ public abstract class WallpaperService extends Service {
         mCallbackLooper = looper;
     }
     
+    /**
+     * Must be implemented to return a new instance of the wallpaper's engine.
+     * Note that multiple instances may be active at the same time, such as
+     * when the wallpaper is currently set as the active wallpaper and the user
+     * is in the wallpaper picker viewing a preview of it as well.
+     */
     public abstract Engine onCreateEngine();
 }
diff --git a/core/java/android/service/wallpaper/WallpaperSettingsActivity.java b/core/java/android/service/wallpaper/WallpaperSettingsActivity.java
index 501947d..aca336f 100644
--- a/core/java/android/service/wallpaper/WallpaperSettingsActivity.java
+++ b/core/java/android/service/wallpaper/WallpaperSettingsActivity.java
@@ -24,6 +24,7 @@ import android.preference.PreferenceActivity;
  * Base class for activities that will be used to configure the settings of
  * a wallpaper.  You should derive from this class to allow it to select the
  * proper theme of the activity depending on how it is being used.
+ * @hide
  */
 public class WallpaperSettingsActivity extends PreferenceActivity {
     /**