4 files changed, 77 insertions, 3 deletions
diff --git a/core/java/android/app/ActivityManagerNative.java b/core/java/android/app/ActivityManagerNative.java
index 541f413..16f0a30 100644
--- a/core/java/android/app/ActivityManagerNative.java
+++ b/core/java/android/app/ActivityManagerNative.java
@@ -998,6 +998,20 @@ public abstract class ActivityManagerNative extends Binder implements IActivityM
             return true;
         }
         
+        case STOP_APP_SWITCHES_TRANSACTION: {
+            data.enforceInterface(IActivityManager.descriptor);
+            stopAppSwitches();
+            reply.writeNoException();
+            return true;
+        }
+        
+        case RESUME_APP_SWITCHES_TRANSACTION: {
+            data.enforceInterface(IActivityManager.descriptor);
+            resumeAppSwitches();
+            reply.writeNoException();
+            return true;
+        }
+        
         case PEEK_SERVICE_TRANSACTION: {
             data.enforceInterface(IActivityManager.descriptor);
             Intent service = Intent.CREATOR.createFromParcel(data);
@@ -2182,5 +2196,25 @@ class ActivityManagerProxy implements IActivityManager
         return res;
     }
     
+    public void stopAppSwitches() throws RemoteException {
+        Parcel data = Parcel.obtain();
+        Parcel reply = Parcel.obtain();
+        data.writeInterfaceToken(IActivityManager.descriptor);
+        mRemote.transact(STOP_APP_SWITCHES_TRANSACTION, data, reply, 0);
+        reply.readException();
+        reply.recycle();
+        data.recycle();
+    }
+    
+    public void resumeAppSwitches() throws RemoteException {
+        Parcel data = Parcel.obtain();
+        Parcel reply = Parcel.obtain();
+        data.writeInterfaceToken(IActivityManager.descriptor);
+        mRemote.transact(RESUME_APP_SWITCHES_TRANSACTION, data, reply, 0);
+        reply.readException();
+        reply.recycle();
+        data.recycle();
+    }
+    
     private IBinder mRemote;
 }
diff --git a/core/java/android/app/IActivityManager.java b/core/java/android/app/IActivityManager.java
index 56b29c1..d15a154 100644
--- a/core/java/android/app/IActivityManager.java
+++ b/core/java/android/app/IActivityManager.java
@@ -44,9 +44,30 @@ import java.util.List;
  * {@hide}
  */
 public interface IActivityManager extends IInterface {
+    /**
+     * Returned by startActivity() if the start request was canceled because
+     * app switches are temporarily canceled to ensure the user's last request
+     * (such as pressing home) is performed.
+     */
+    public static final int START_SWITCHES_CANCELED = 4;
+    /**
+     * Returned by startActivity() if an activity wasn't really started, but
+     * the given Intent was given to the existing top activity.
+     */
     public static final int START_DELIVERED_TO_TOP = 3;
+    /**
+     * Returned by startActivity() if an activity wasn't really started, but
+     * a task was simply brought to the foreground.
+     */
     public static final int START_TASK_TO_FRONT = 2;
+    /**
+     * Returned by startActivity() if the caller asked that the Intent not
+     * be executed if it is the recipient, and that is indeed the case.
+     */
     public static final int START_RETURN_INTENT_TO_CALLER = 1;
+    /**
+     * Activity was started successfully as normal.
+     */
     public static final int START_SUCCESS = 0;
     public static final int START_INTENT_NOT_RESOLVED = -1;
     public static final int START_CLASS_NOT_FOUND = -2;
@@ -225,6 +246,9 @@ public interface IActivityManager extends IInterface {
     
     public boolean shutdown(int timeout) throws RemoteException;
     
+    public void stopAppSwitches() throws RemoteException;
+    public void resumeAppSwitches() throws RemoteException;
+    
     /*
      * Private non-Binder interfaces
      */
@@ -371,4 +395,6 @@ public interface IActivityManager extends IInterface {
     int PEEK_SERVICE_TRANSACTION = IBinder.FIRST_CALL_TRANSACTION+84;
     int PROFILE_CONTROL_TRANSACTION = IBinder.FIRST_CALL_TRANSACTION+85;
     int SHUTDOWN_TRANSACTION = IBinder.FIRST_CALL_TRANSACTION+86;
+    int STOP_APP_SWITCHES_TRANSACTION = IBinder.FIRST_CALL_TRANSACTION+87;
+    int RESUME_APP_SWITCHES_TRANSACTION = IBinder.FIRST_CALL_TRANSACTION+88;
 }
diff --git a/core/res/AndroidManifest.xml b/core/res/AndroidManifest.xml
index ca2db11..b5f3a0f 100644
--- a/core/res/AndroidManifest.xml
+++ b/core/res/AndroidManifest.xml
@@ -803,14 +803,22 @@
         android:description="@string/permdesc_runSetActivityWatcher"
         android:protectionLevel="signature" />
 
-    <!-- Allows an application to watch and control how activities are
-         started globally in the system.  Only for is in debugging
-         (usually the monkey command). -->
+    <!-- Allows an application to call the activity manager shutdown() API
+         to put the higher-level system there into a shutdown state. -->
     <permission android:name="android.permission.SHUTDOWN"
         android:label="@string/permlab_shutdown"
         android:description="@string/permdesc_shutdown"
         android:protectionLevel="signature" />
 
+    <!-- Allows an application to tell the activity manager to temporarily
+         stop application switches, putting it into a special mode that
+         prevents applications from immediately switching away from some
+         critical UI such as the home screen. -->
+    <permission android:name="android.permission.STOP_APP_SWITCHES"
+        android:label="@string/permlab_stopAppSwitches"
+        android:description="@string/permdesc_stopAppSwitches"
+        android:protectionLevel="signature" />
+
     <!-- Allows an application to retrieve the current state of keys and
          switches.  This is only for use by the system.-->
     <permission android:name="android.permission.READ_INPUT_STATE"
diff --git a/core/res/res/values/strings.xml b/core/res/res/values/strings.xml
index 058a445..4a6a564 100644
--- a/core/res/res/values/strings.xml
+++ b/core/res/res/values/strings.xml
@@ -473,6 +473,12 @@
         state.  Does not perform a complete shutdown.</string>
 
     <!-- Title of an application permission, listed so the user can choose whether they want to allow the application to do this. -->
+    <string name="permlab_stopAppSwitches">prevent app switches</string>
+    <!-- Description of an application permission, listed so the user can choose whether they want to allow the application to do this. -->
+    <string name="permdesc_stopAppSwitches">Prevents the user from switching to
+        another application.</string>
+
+    <!-- Title of an application permission, listed so the user can choose whether they want to allow the application to do this. -->
     <string name="permlab_runSetActivityWatcher">monitor and control all application launching</string>
     <!-- Description of an application permission, listed so the user can choose whether they want to allow the application to do this. -->
     <string name="permdesc_runSetActivityWatcher">Allows an application to