Rotation lock.

IWindowManager now supports two new methods,
freezeRotation() and thawRotation(), that allow a caller to
temporarily stash the device's current rotation as the
default rotation (when no other constraints are present).

The system bar uses this to implement a user-accessible
rotation lock by calling freezeRotation() and then turning
off accelerometer-based display rotation; unless overridden
by an app, the display will continue to appear in the frozen
rotation until the rotation is unlocked by the user (either
via the rotation lock icon in the system bar or by checking
"rotate screen automatically" in Settings).

Bug: 2949639
Change-Id: Icd21c169d1053719590e72401f229424b254622f

3 files changed, 41 insertions, 0 deletions

diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index 2229964..9c72dec 100644
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -1573,6 +1573,16 @@ public final class Settings {
         public static final String ACCELEROMETER_ROTATION = "accelerometer_rotation";
 
         /**
+         * Default screen rotation when no other policy applies.
+         * When {@link #ACCELEROMETER_ROTATION} is zero and no on-screen Activity expresses a
+         * preference, this rotation value will be used. Must be one of the
+         * {@link android.view.Surface#ROTATION_0 Surface rotation constants}. 
+         *
+         * @see Display#getRotation
+         */
+        public static final String USER_ROTATION = "user_rotation";
+
+        /**
          * Whether the audible DTMF tones are played by the dialer when dialing. The value is
          * boolean (1 or 0).
          */
@@ -1806,6 +1816,7 @@ public final class Settings {
             TIME_12_24,
             DATE_FORMAT,
             ACCELEROMETER_ROTATION,
+            USER_ROTATION,
             DTMF_TONE_WHEN_DIALING,
             DTMF_TONE_TYPE_WHEN_DIALING,
             EMERGENCY_TONE,
diff --git a/core/java/android/view/IWindowManager.aidl b/core/java/android/view/IWindowManager.aidl
index d4dd05c..a54f342 100644
--- a/core/java/android/view/IWindowManager.aidl
+++ b/core/java/android/view/IWindowManager.aidl
@@ -156,4 +156,17 @@ interface IWindowManager
      * calls back when it changes.
      */
     int watchRotation(IRotationWatcher watcher);
+
+	/**
+	 * Lock the device orientation to the current rotation. Sensor input will
+	 * be ignored until thawRotation() is called.
+	 * @hide
+	 */
+	void freezeRotation();
+
+	/**
+	 * Release the orientation lock imposed by freezeRotation().
+	 * @hide
+	 */
+	void thawRotation();
 }
diff --git a/core/java/android/view/WindowManagerPolicy.java b/core/java/android/view/WindowManagerPolicy.java
index 1a341e1..e78d6a8 100644
--- a/core/java/android/view/WindowManagerPolicy.java
+++ b/core/java/android/view/WindowManagerPolicy.java
@@ -362,6 +362,13 @@ public interface WindowManagerPolicy {
      * modify the rotation.
      */
     public final int USE_LAST_ROTATION = -1000;
+
+    /** When not otherwise specified by the activity's screenOrientation, rotation should be
+     * determined by the system (that is, using sensors). */
+    public final int USER_ROTATION_FREE = 0;
+    /** When not otherwise specified by the activity's screenOrientation, rotation is set by
+     * the user. */
+    public final int USER_ROTATION_LOCKED = 1;
     
     /**
      * Perform initialization of the policy.
@@ -787,4 +794,14 @@ public interface WindowManagerPolicy {
      * Return false to disable key repeat events from being generated.
      */
     public boolean allowKeyRepeat();
+
+    /**
+     * Inform the policy that the user has chosen a preferred orientation ("rotation lock"). 
+     *
+     * @param mode One of {@link WindowManagerPolicy#USER_ROTATION_LOCKED} or
+     *             {@link * WindowManagerPolicy#USER_ROTATION_FREE}. 
+     * @param rotation One of {@link Surface#ROTATION_0}, {@link Surface#ROTATION_90},
+     *                 {@link Surface#ROTATION_180}, {@link Surface#ROTATION_270}. 
+     */
+    public void setUserRotationMode(int mode, int rotation);
 }