Various work on out of memory managment.

- Improve how we handle processes that have shown UI, to take care
  of more cases where we want to push them into the background LRU
  list.
- New trim memory level for when an application that has done UI
  is no longer visible to the user.
- Add APIs to get new trim memory callback.
- Add a host of new bind flags to tweak how the system will adjust
  the OOM level of the target process.

Change-Id: I23ba354112f411a9f8773a67426b4dff85fa2439

7 files changed, 225 insertions, 23 deletions

diff --git a/core/java/android/app/Activity.java b/core/java/android/app/Activity.java
index fb1570e..d5b669e 100644
--- a/core/java/android/app/Activity.java
+++ b/core/java/android/app/Activity.java
@@ -19,7 +19,7 @@ package android.app;
 import com.android.internal.app.ActionBarImpl;
 import com.android.internal.policy.PolicyManager;
 
-import android.content.ComponentCallbacks;
+import android.content.ComponentCallbacks2;
 import android.content.ComponentName;
 import android.content.ContentResolver;
 import android.content.Context;
@@ -626,7 +626,7 @@ import java.util.HashMap;
 public class Activity extends ContextThemeWrapper
         implements LayoutInflater.Factory2,
         Window.Callback, KeyEvent.Callback,
-        OnCreateContextMenuListener, ComponentCallbacks {
+        OnCreateContextMenuListener, ComponentCallbacks2 {
     private static final String TAG = "Activity";
 
     /** Standard activity result: operation canceled. */
@@ -859,6 +859,7 @@ public class Activity extends ContextThemeWrapper
                     ? mLastNonConfigurationInstances.fragments : null);
         }
         mFragments.dispatchCreate();
+        getApplication().dispatchActivityCreated(this, savedInstanceState);
         mCalled = true;
     }
 
@@ -1001,6 +1002,8 @@ public class Activity extends ContextThemeWrapper
             }
             mCheckedForLoaderManager = true;
         }
+
+        getApplication().dispatchActivityStarted(this);
     }
 
     /**
@@ -1048,6 +1051,7 @@ public class Activity extends ContextThemeWrapper
      * @see #onPause
      */
     protected void onResume() {
+        getApplication().dispatchActivityResumed(this);
         mCalled = true;
     }
 
@@ -1158,6 +1162,7 @@ public class Activity extends ContextThemeWrapper
         if (p != null) {
             outState.putParcelable(FRAGMENTS_TAG, p);
         }
+        getApplication().dispatchActivitySaveInstanceState(this, outState);
     }
 
     /**
@@ -1234,6 +1239,7 @@ public class Activity extends ContextThemeWrapper
      * @see #onStop
      */
     protected void onPause() {
+        getApplication().dispatchActivityPaused(this);
         mCalled = true;
     }
 
@@ -1320,6 +1326,7 @@ public class Activity extends ContextThemeWrapper
      */
     protected void onStop() {
         if (mActionBar != null) mActionBar.setShowHideAnimationEnabled(false);
+        getApplication().dispatchActivityStopped(this);
         mCalled = true;
     }
 
@@ -1382,6 +1389,8 @@ public class Activity extends ContextThemeWrapper
         if (mSearchManager != null) {
             mSearchManager.stopSearch();
         }
+
+        getApplication().dispatchActivityDestroyed(this);
     }
 
     /**
@@ -1580,12 +1589,17 @@ public class Activity extends ContextThemeWrapper
         nci.loaders = mAllLoaderManagers;
         return nci;
     }
-    
+
     public void onLowMemory() {
         mCalled = true;
         mFragments.dispatchLowMemory();
     }
-    
+
+    public void onTrimMemory(int level) {
+        mCalled = true;
+        mFragments.dispatchTrimMemory(level);
+    }
+
     /**
      * Return the FragmentManager for interacting with fragments associated
      * with this activity.
diff --git a/core/java/android/app/ActivityThread.java b/core/java/android/app/ActivityThread.java
index 1e93f88..8931675 100644
--- a/core/java/android/app/ActivityThread.java
+++ b/core/java/android/app/ActivityThread.java
@@ -18,7 +18,7 @@ package android.app;
 
 import android.app.backup.BackupAgent;
 import android.content.BroadcastReceiver;
-import android.content.ComponentCallbacks;
+import android.content.ComponentCallbacks2;
 import android.content.ComponentName;
 import android.content.ContentProvider;
 import android.content.Context;
@@ -3258,10 +3258,10 @@ public final class ActivityThread {
         }
     }
 
-    ArrayList<ComponentCallbacks> collectComponentCallbacksLocked(
+    ArrayList<ComponentCallbacks2> collectComponentCallbacksLocked(
             boolean allActivities, Configuration newConfig) {
-        ArrayList<ComponentCallbacks> callbacks
-                = new ArrayList<ComponentCallbacks>();
+        ArrayList<ComponentCallbacks2> callbacks
+                = new ArrayList<ComponentCallbacks2>();
 
         if (mActivities.size() > 0) {
             Iterator<ActivityClientRecord> it = mActivities.values().iterator();
@@ -3311,10 +3311,10 @@ public final class ActivityThread {
         return callbacks;
     }
 
-    private void performConfigurationChanged(
-            ComponentCallbacks cb, Configuration config) {
+    private final void performConfigurationChanged(
+            ComponentCallbacks2 cb, Configuration config) {
         // Only for Activity objects, check that they actually call up to their
-        // superclass implementation.  ComponentCallbacks is an interface, so
+        // superclass implementation.  ComponentCallbacks2 is an interface, so
         // we check the runtime type and act accordingly.
         Activity activity = (cb instanceof Activity) ? (Activity) cb : null;
         if (activity != null) {
@@ -3418,7 +3418,7 @@ public final class ActivityThread {
     
     final void handleConfigurationChanged(Configuration config, CompatibilityInfo compat) {
 
-        ArrayList<ComponentCallbacks> callbacks = null;
+        ArrayList<ComponentCallbacks2> callbacks = null;
 
         synchronized (mPackages) {
             if (mPendingConfiguration != null) {
@@ -3558,7 +3558,7 @@ public final class ActivityThread {
     }
         
     final void handleLowMemory() {
-        ArrayList<ComponentCallbacks> callbacks;
+        ArrayList<ComponentCallbacks2> callbacks;
 
         synchronized (mPackages) {
             callbacks = collectComponentCallbacksLocked(true, null);
@@ -3583,6 +3583,16 @@ public final class ActivityThread {
 
     final void handleTrimMemory(int level) {
         WindowManagerImpl.getDefault().trimMemory(level);
+        ArrayList<ComponentCallbacks2> callbacks;
+
+        synchronized (mPackages) {
+            callbacks = collectComponentCallbacksLocked(true, null);
+        }
+
+        final int N = callbacks.size();
+        for (int i=0; i<N; i++) {
+            callbacks.get(i).onTrimMemory(level);
+        }
     }
 
     private void handleBindApplication(AppBindData data) {
@@ -4128,7 +4138,7 @@ public final class ActivityThread {
             }
         }
         
-        ViewRootImpl.addConfigCallback(new ComponentCallbacks() {
+        ViewRootImpl.addConfigCallback(new ComponentCallbacks2() {
             public void onConfigurationChanged(Configuration newConfig) {
                 synchronized (mPackages) {
                     // We need to apply this change to the resources
@@ -4148,6 +4158,8 @@ public final class ActivityThread {
             }
             public void onLowMemory() {
             }
+            public void onTrimMemory(int level) {
+            }
         });
     }
 
diff --git a/core/java/android/app/Application.java b/core/java/android/app/Application.java
index 10cc9f8..dd9ea26 100644
--- a/core/java/android/app/Application.java
+++ b/core/java/android/app/Application.java
@@ -16,10 +16,14 @@
 
 package android.app;
 
+import java.util.ArrayList;
+
 import android.content.ComponentCallbacks;
+import android.content.ComponentCallbacks2;
 import android.content.Context;
 import android.content.ContextWrapper;
 import android.content.res.Configuration;
+import android.os.Bundle;
 
 /**
  * Base class for those who need to maintain global application state. You can
@@ -36,10 +40,25 @@ import android.content.res.Configuration;
  * {@link android.content.Context#getApplicationContext() Context.getApplicationContext()}
  * when first constructing the singleton.</p>
  */
-public class Application extends ContextWrapper implements ComponentCallbacks {
+public class Application extends ContextWrapper implements ComponentCallbacks2 {
+    private ArrayList<ComponentCallbacks> mComponentCallbacks =
+            new ArrayList<ComponentCallbacks>();
+    private ArrayList<ActivityLifecycleCallbacks> mActivityLifecycleCallbacks =
+            new ArrayList<ActivityLifecycleCallbacks>();
+
     /** @hide */
     public LoadedApk mLoadedApk;
-    
+
+    public interface ActivityLifecycleCallbacks {
+        void onActivityCreated(Activity activity, Bundle savedInstanceState);
+        void onActivityStarted(Activity activity);
+        void onActivityResumed(Activity activity);
+        void onActivityPaused(Activity activity);
+        void onActivityStopped(Activity activity);
+        void onActivitySaveInstanceState(Activity activity, Bundle outState);
+        void onActivityDestroyed(Activity activity);
+    }
+
     public Application() {
         super(null);
     }
@@ -63,11 +82,59 @@ public class Application extends ContextWrapper implements ComponentCallbacks {
      */
     public void onTerminate() {
     }
-    
+
     public void onConfigurationChanged(Configuration newConfig) {
+        Object[] callbacks = collectComponentCallbacks();
+        if (callbacks != null) {
+            for (int i=0; i<callbacks.length; i++) {
+                ((ComponentCallbacks)callbacks[i]).onConfigurationChanged(newConfig);
+            }
+        }
     }
-    
+
     public void onLowMemory() {
+        Object[] callbacks = collectComponentCallbacks();
+        if (callbacks != null) {
+            for (int i=0; i<callbacks.length; i++) {
+                ((ComponentCallbacks)callbacks[i]).onLowMemory();
+            }
+        }
+    }
+
+    public void onTrimMemory(int level) {
+        Object[] callbacks = collectComponentCallbacks();
+        if (callbacks != null) {
+            for (int i=0; i<callbacks.length; i++) {
+                Object c = callbacks[i];
+                if (c instanceof ComponentCallbacks2) {
+                    ((ComponentCallbacks2)c).onTrimMemory(level);
+                }
+            }
+        }
+    }
+
+    public void registerComponentCallbacks(ComponentCallbacks callback) {
+        synchronized (mComponentCallbacks) {
+            mComponentCallbacks.add(callback);
+        }
+    }
+
+    public void unregisterComponentCallbacks(ComponentCallbacks callback) {
+        synchronized (mComponentCallbacks) {
+            mComponentCallbacks.remove(callback);
+        }
+    }
+
+    public void registerActivityLifecycleCallbacks(ActivityLifecycleCallbacks callback) {
+        synchronized (mActivityLifecycleCallbacks) {
+            mActivityLifecycleCallbacks.add(callback);
+        }
+    }
+
+    public void unregisterActivityLifecycleCallbacks(ActivityLifecycleCallbacks callback) {
+        synchronized (mActivityLifecycleCallbacks) {
+            mActivityLifecycleCallbacks.remove(callback);
+        }
     }
     
     // ------------------ Internal API ------------------
@@ -79,4 +146,89 @@ public class Application extends ContextWrapper implements ComponentCallbacks {
         attachBaseContext(context);
         mLoadedApk = ContextImpl.getImpl(context).mPackageInfo;
     }
+
+    /* package */ void dispatchActivityCreated(Activity activity, Bundle savedInstanceState) {
+        Object[] callbacks = collectActivityLifecycleCallbacks();
+        if (callbacks != null) {
+            for (int i=0; i<callbacks.length; i++) {
+                ((ActivityLifecycleCallbacks)callbacks[i]).onActivityCreated(activity,
+                        savedInstanceState);
+            }
+        }
+    }
+
+    /* package */ void dispatchActivityStarted(Activity activity) {
+        Object[] callbacks = collectActivityLifecycleCallbacks();
+        if (callbacks != null) {
+            for (int i=0; i<callbacks.length; i++) {
+                ((ActivityLifecycleCallbacks)callbacks[i]).onActivityStarted(activity);
+            }
+        }
+    }
+
+    /* package */ void dispatchActivityResumed(Activity activity) {
+        Object[] callbacks = collectActivityLifecycleCallbacks();
+        if (callbacks != null) {
+            for (int i=0; i<callbacks.length; i++) {
+                ((ActivityLifecycleCallbacks)callbacks[i]).onActivityResumed(activity);
+            }
+        }
+    }
+
+    /* package */ void dispatchActivityPaused(Activity activity) {
+        Object[] callbacks = collectActivityLifecycleCallbacks();
+        if (callbacks != null) {
+            for (int i=0; i<callbacks.length; i++) {
+                ((ActivityLifecycleCallbacks)callbacks[i]).onActivityPaused(activity);
+            }
+        }
+    }
+
+    /* package */ void dispatchActivityStopped(Activity activity) {
+        Object[] callbacks = collectActivityLifecycleCallbacks();
+        if (callbacks != null) {
+            for (int i=0; i<callbacks.length; i++) {
+                ((ActivityLifecycleCallbacks)callbacks[i]).onActivityStopped(activity);
+            }
+        }
+    }
+
+    /* package */ void dispatchActivitySaveInstanceState(Activity activity, Bundle outState) {
+        Object[] callbacks = collectActivityLifecycleCallbacks();
+        if (callbacks != null) {
+            for (int i=0; i<callbacks.length; i++) {
+                ((ActivityLifecycleCallbacks)callbacks[i]).onActivitySaveInstanceState(activity,
+                        outState);
+            }
+        }
+    }
+
+    /* package */ void dispatchActivityDestroyed(Activity activity) {
+        Object[] callbacks = collectActivityLifecycleCallbacks();
+        if (callbacks != null) {
+            for (int i=0; i<callbacks.length; i++) {
+                ((ActivityLifecycleCallbacks)callbacks[i]).onActivityDestroyed(activity);
+            }
+        }
+    }
+
+    private Object[] collectComponentCallbacks() {
+        Object[] callbacks = null;
+        synchronized (mComponentCallbacks) {
+            if (mComponentCallbacks.size() > 0) {
+                callbacks = mComponentCallbacks.toArray();
+            }
+        }
+        return callbacks;
+    }
+
+    private Object[] collectActivityLifecycleCallbacks() {
+        Object[] callbacks = null;
+        synchronized (mActivityLifecycleCallbacks) {
+            if (mActivityLifecycleCallbacks.size() > 0) {
+                callbacks = mActivityLifecycleCallbacks.toArray();
+            }
+        }
+        return callbacks;
+    }
 }
diff --git a/core/java/android/app/ContextImpl.java b/core/java/android/app/ContextImpl.java
index a99cec2..b4bdb2f 100644
--- a/core/java/android/app/ContextImpl.java
+++ b/core/java/android/app/ContextImpl.java
@@ -1109,6 +1109,12 @@ class ContextImpl extends Context {
             throw new RuntimeException("Not supported in system context");
         }
         try {
+            IBinder token = getActivityToken();
+            if (token == null && (flags&BIND_AUTO_CREATE) == 0 && mPackageInfo != null
+                    && mPackageInfo.getApplicationInfo().targetSdkVersion
+                    < android.os.Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
+                flags |= BIND_WAIVE_PRIORITY;
+            }
             int res = ActivityManagerNative.getDefault().bindService(
                 mMainThread.getApplicationThread(), getActivityToken(),
                 service, service.resolveTypeIfNeeded(getContentResolver()),
diff --git a/core/java/android/app/Fragment.java b/core/java/android/app/Fragment.java
index e2746d4..371e7ad 100644
--- a/core/java/android/app/Fragment.java
+++ b/core/java/android/app/Fragment.java
@@ -17,7 +17,7 @@
 package android.app;
 
 import android.animation.Animator;
-import android.content.ComponentCallbacks;
+import android.content.ComponentCallbacks2;
 import android.content.Context;
 import android.content.Intent;
 import android.content.res.Configuration;
@@ -332,7 +332,7 @@ final class FragmentState implements Parcelable {
  * pressing back will pop it to return the user to whatever previous state
  * the activity UI was in.
  */
-public class Fragment implements ComponentCallbacks, OnCreateContextMenuListener {
+public class Fragment implements ComponentCallbacks2, OnCreateContextMenuListener {
     private static final HashMap<String, Class<?>> sClassMap =
             new HashMap<String, Class<?>>();
     
@@ -1182,6 +1182,10 @@ public class Fragment implements ComponentCallbacks, OnCreateContextMenuListener
         mCalled = true;
     }
     
+    public void onTrimMemory(int level) {
+        mCalled = true;
+    }
+
     /**
      * Called when the view previously created by {@link #onCreateView} has
      * been detached from the fragment.  The next time the fragment needs
diff --git a/core/java/android/app/FragmentManager.java b/core/java/android/app/FragmentManager.java
index 24550c5..c33ab2c 100644
--- a/core/java/android/app/FragmentManager.java
+++ b/core/java/android/app/FragmentManager.java
@@ -1722,6 +1722,17 @@ final class FragmentManagerImpl extends FragmentManager {
         }
     }
 
+    public void dispatchTrimMemory(int level) {
+        if (mActive != null) {
+            for (int i=0; i<mAdded.size(); i++) {
+                Fragment f = mAdded.get(i);
+                if (f != null) {
+                    f.onTrimMemory(level);
+                }
+            }
+        }
+    }
+
     public boolean dispatchCreateOptionsMenu(Menu menu, MenuInflater inflater) {
         boolean show = false;
         ArrayList<Fragment> newMenus = null;
diff --git a/core/java/android/app/Service.java b/core/java/android/app/Service.java
index 4c21d04..ebde6e0 100644
--- a/core/java/android/app/Service.java
+++ b/core/java/android/app/Service.java
@@ -16,7 +16,7 @@
 
 package android.app;
 
-import android.content.ComponentCallbacks;
+import android.content.ComponentCallbacks2;
 import android.content.ComponentName;
 import android.content.Intent;
 import android.content.ContextWrapper;
@@ -274,7 +274,7 @@ import java.io.PrintWriter;
  * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/MessengerServiceActivities.java
  *      bind}
  */
-public abstract class Service extends ContextWrapper implements ComponentCallbacks {
+public abstract class Service extends ContextWrapper implements ComponentCallbacks2 {
     private static final String TAG = "Service";
 
     public Service() {
@@ -451,7 +451,10 @@ public abstract class Service extends ContextWrapper implements ComponentCallbac
     
     public void onLowMemory() {
     }
-    
+
+    public void onTrimMemory(int level) {
+    }
+
     /**
      * Return the communication channel to the service.  May return null if 
      * clients can not bind to the service.  The returned