Add setting to disable camera gesture

Bug: 22183841
Change-Id: I6ada3d2c911fd52e2821f12f3db5d549879941f4

res/values/strings.xml

@@ -6949,4 +6949,11 @@
     <string name="write_settings_on">Yes</string>
     <!-- Summary of app not allowed to write system settings [CHAR LIMIT=45] -->
     <string name="write_settings_off">No</string>
+
+    <!-- Title of setting that controls gesture to open camera [CHAR LIMIT=40] -->
+    <string name="camera_gesture_title">Double twist for camera</string>
+
+    <!-- Description of setting that controls gesture to open camera [CHAR LIMIT=NONE] -->
+    <string name="camera_gesture_desc">Open the camera app by twisting your wrist twice</string>
+
 </resources>

res/xml/display_settings.xml

@@ -57,6 +57,12 @@
                 android:entries="@array/screen_timeout_entries"
                 android:entryValues="@array/screen_timeout_values" />
 
+        <SwitchPreference
+                android:key="camera_gesture"
+                android:title="@string/camera_gesture_title"
+                android:summary="@string/camera_gesture_desc"
+                android:persistent="false" />
+
         <PreferenceScreen
                 android:key="screensaver"
                 android:title="@string/screensaver_settings_title"

src/com/android/settings/DisplaySettings.java

@@ -22,6 +22,7 @@ import com.android.settings.DropDownPreference.Callback;
 import com.android.settings.search.BaseSearchIndexProvider;
 import com.android.settings.search.Indexable;
 
+import static android.provider.Settings.Secure.CAMERA_GESTURE_DISABLED;
 import static android.provider.Settings.Secure.DOUBLE_TAP_TO_WAKE;
 import static android.provider.Settings.Secure.DOZE_ENABLED;
 import static android.provider.Settings.Secure.WAKE_GESTURE_ENABLED;
@@ -74,6 +75,7 @@ public class DisplaySettings extends SettingsPreferenceFragment implements
     private static final String KEY_AUTO_BRIGHTNESS = "auto_brightness";
     private static final String KEY_AUTO_ROTATE = "auto_rotate";
     private static final String KEY_NIGHT_MODE = "night_mode";
+    private static final String KEY_CAMERA_GESTURE = "camera_gesture";
 
     private static final int DLG_GLOBAL_CHANGE_WARNING = 1;
 
@@ -88,6 +90,7 @@ public class DisplaySettings extends SettingsPreferenceFragment implements
     private SwitchPreference mDozePreference;
     private SwitchPreference mTapToWakePreference;
     private SwitchPreference mAutoBrightnessPreference;
+    private SwitchPreference mCameraGesturePreference;
 
     @Override
     protected int getMetricsCategory() {
@@ -149,6 +152,13 @@ public class DisplaySettings extends SettingsPreferenceFragment implements
             removePreference(KEY_TAP_TO_WAKE);
         }
 
+        if (isCameraGestureAvailable(getResources())) {
+            mCameraGesturePreference = (SwitchPreference) findPreference(KEY_CAMERA_GESTURE);
+            mCameraGesturePreference.setOnPreferenceChangeListener(this);
+        } else {
+            removePreference(KEY_CAMERA_GESTURE);
+        }
+
         if (RotationPolicy.isRotationLockToggleVisible(activity)) {
             DropDownPreference rotatePreference =
                     (DropDownPreference) findPreference(KEY_AUTO_ROTATE);
@@ -224,6 +234,13 @@ public class DisplaySettings extends SettingsPreferenceFragment implements
         return res.getBoolean(com.android.internal.R.bool.config_automatic_brightness_available);
     }
 
+    private static boolean isCameraGestureAvailable(Resources res) {
+        boolean configSet = res.getInteger(
+                com.android.internal.R.integer.config_cameraLaunchGestureSensorType) != -1;
+        return configSet &&
+                !SystemProperties.getBoolean("gesture.disable_camera_launch", false);
+    }
+
     private void updateTimeoutPreferenceDescription(long currentTimeout) {
         ListPreference preference = mScreenTimeoutPreference;
         String summary;
@@ -370,6 +387,12 @@ public class DisplaySettings extends SettingsPreferenceFragment implements
             int value = Settings.Secure.getInt(getContentResolver(), DOUBLE_TAP_TO_WAKE, 0);
             mTapToWakePreference.setChecked(value != 0);
         }
+
+        // Update camera gesture if it is available.
+        if (mCameraGesturePreference != null) {
+            int value = Settings.Secure.getInt(getContentResolver(), CAMERA_GESTURE_DISABLED, 0);
+            mCameraGesturePreference.setChecked(value == 0);
+        }
     }
 
     private void updateScreenSaverSummary() {
@@ -425,6 +448,11 @@ public class DisplaySettings extends SettingsPreferenceFragment implements
             boolean value = (Boolean) objValue;
             Settings.Secure.putInt(getContentResolver(), DOUBLE_TAP_TO_WAKE, value ? 1 : 0);
         }
+        if (preference == mCameraGesturePreference) {
+            boolean value = (Boolean) objValue;
+            Settings.Secure.putInt(getContentResolver(), CAMERA_GESTURE_DISABLED,
+                    value ? 0 : 1 /* Backwards because setting is for disabling */);
+        }
         if (preference == mNightModePreference) {
             try {
                 final int value = Integer.parseInt((String) objValue);
@@ -493,6 +521,9 @@ public class DisplaySettings extends SettingsPreferenceFragment implements
                     if (!isTapToWakeAvailable(context.getResources())) {
                         result.add(KEY_TAP_TO_WAKE);
                     }
+                    if (!isCameraGestureAvailable(context.getResources())) {
+                        result.add(KEY_CAMERA_GESTURE);
+                    }
                     return result;
                 }
             };