Add Preference#onDetachedFromActivity

Change-Id: I7c78f96d41b33b902e54fe1c0b7246d555aab0ed

api/current.txt

@@ -23885,6 +23885,7 @@ package android.preference {
     method protected void onClick();
     method protected android.view.View onCreateView(android.view.ViewGroup);
     method public void onDependencyChanged(android.preference.Preference, boolean);
+    method protected void onDetachedFromActivity();
     method protected java.lang.Object onGetDefaultValue(android.content.res.TypedArray, int);
     method public void onParentChanged(android.preference.Preference, boolean);
     method protected void onPrepareForRemoval();

api/system-current.txt

@@ -25841,6 +25841,7 @@ package android.preference {
     method protected void onClick();
     method protected android.view.View onCreateView(android.view.ViewGroup);
     method public void onDependencyChanged(android.preference.Preference, boolean);
+    method protected void onDetachedFromActivity();
     method protected java.lang.Object onGetDefaultValue(android.content.res.TypedArray, int);
     method public void onParentChanged(android.preference.Preference, boolean);
     method protected void onPrepareForRemoval();

core/java/android/preference/Preference.java

@@ -1184,9 +1184,10 @@ public class Preference implements Comparable<Preference> {
     
     /**
      * Called when the Preference hierarchy has been attached to the
-     * {@link PreferenceActivity}. This can also be called when this
-     * Preference has been attached to a group that was already attached
-     * to the {@link PreferenceActivity}.
+     * {@link PreferenceActivity} or {@link PreferenceFragment}. This can
+     * also be called when this Preference has been attached to a group
+     * that was already attached to the {@link PreferenceActivity} or
+     * {@link PreferenceFragment}.
      */
     protected void onAttachedToActivity() {
         // At this point, the hierarchy that this preference is in is connected
@@ -1194,6 +1195,16 @@ public class Preference implements Comparable<Preference> {
         registerDependency();
     }
 
+    /**
+     * Called when the Preference hierarchy has been detached from the
+     * {@link PreferenceActivity} or {@link PreferenceFragment}. This can
+     * also be called when this Preference has been removed from a group
+     * that was already attached to the {@link PreferenceActivity} or
+     * {@link PreferenceFragment}.
+     */
+    protected void onDetachedFromActivity() {
+    }
+
     private void registerDependency() {
         
         if (TextUtils.isEmpty(mDependencyKey)) return;

core/java/android/preference/PreferenceGroup.java

@@ -187,7 +187,11 @@ public abstract class PreferenceGroup extends Preference implements GenericInfla
     private boolean removePreferenceInt(Preference preference) {
         synchronized(this) {
             preference.onPrepareForRemoval();
-            return mPreferenceList.remove(preference);
+            boolean success = mPreferenceList.remove(preference);
+            if (mAttachedToActivity) {
+                preference.onDetachedFromActivity();
+            }
+            return success;
         }
     }
     
@@ -263,7 +267,7 @@ public abstract class PreferenceGroup extends Preference implements GenericInfla
     protected boolean isOnSameScreenAsChildren() {
         return true;
     }
-    
+
     @Override
     protected void onAttachedToActivity() {
         super.onAttachedToActivity();
@@ -280,11 +284,17 @@ public abstract class PreferenceGroup extends Preference implements GenericInfla
     }
 
     @Override
-    protected void onPrepareForRemoval() {
-        super.onPrepareForRemoval();
-        
+    protected void onDetachedFromActivity() {
+        super.onDetachedFromActivity();
+
         // We won't be attached to the activity anymore
         mAttachedToActivity = false;
+
+        // Dispatch to all contained preferences
+        final int preferenceCount = getPreferenceCount();
+        for (int i = 0; i < preferenceCount; i++) {
+            getPreference(i).onDetachedFromActivity();
+        }
     }
 
     @Override

core/java/android/preference/PreferenceManager.java

@@ -396,6 +396,9 @@ public class PreferenceManager {
      */
     boolean setPreferences(PreferenceScreen preferenceScreen) {
         if (preferenceScreen != mPreferenceScreen) {
+            if (mPreferenceScreen != null) {
+                mPreferenceScreen.onDetachedFromActivity();
+            }
             mPreferenceScreen = preferenceScreen;
             return true;
         }
@@ -704,7 +707,11 @@ public class PreferenceManager {
      */
     void dispatchActivityDestroy() {
         List<OnActivityDestroyListener> list = null;
-        
+
+        if (mPreferenceScreen != null) {
+            mPreferenceScreen.onDetachedFromActivity();
+            mPreferenceScreen = null;
+        }
         synchronized (this) {
             if (mActivityDestroyListeners != null) {
                 list = new ArrayList<OnActivityDestroyListener>(mActivityDestroyListeners);