Use a custom annotation interface for scroll direction

It's safer and improves the understandability of the code. The new
definitions replaced the old DEFAULT value by NATURAL which matches
what we show in the UI. There is still the need for an invalid value
(-1 in this case) because we apply caching and we need to know
whether the value has been initialized.

Author: svillar

app/src/common/shared/com/igalia/wolvic/VRBrowserActivity.java

@@ -1221,7 +1221,7 @@ void handleScrollEvent(final int aHandle, final int aDevice, final float aX, fin
                     return;
                 }
             }
-            float scrollDirection = mSettings.getScrollDirection() == 0 ? 1.0f : -1.0f;
+            float scrollDirection = mSettings.getScrollDirection() == SettingsStore.SCROLL_DIRECTION_NATURAL ? 1.0f : -1.0f;
             MotionEventGenerator.dispatchScroll(widget, aDevice, true,aX * scrollDirection, aY * scrollDirection);
         });
     }

app/src/common/shared/com/igalia/wolvic/browser/SettingsStore.java

@@ -83,6 +83,13 @@ SettingsStore getInstance(final @NonNull Context aContext) {
     public static final int WINDOW_SELECTION_METHOD_CLICK = 0;
     public static final int WINDOW_SELECTION_METHOD_HOVER = 1;
 
+    // Keep in sync with developer_options_pointer_scroll_direction_values array in option_values.xml
+    @IntDef(value = {SCROLL_DIRECTION_INVALID, SCROLL_DIRECTION_NATURAL, SCROLL_DIRECTION_REVERSED})
+    public @interface ScrollDirection {}
+    public static final int SCROLL_DIRECTION_INVALID = -1;
+    public static final int SCROLL_DIRECTION_NATURAL = 0;
+    public static final int SCROLL_DIRECTION_REVERSED = 1;
+
     private Context mContext;
     private SharedPreferences mPrefs;
     private SettingsViewModel mSettingsViewModel;
@@ -151,7 +158,6 @@ public static WindowSizePreset fromValues(int width, int height) {
 
     public final static @WindowSelectionMethod int WINDOW_SELECTION_METHOD_DEFAULT = WINDOW_SELECTION_METHOD_HOVER;
     public final static int POINTER_COLOR_DEFAULT_DEFAULT = Color.parseColor("#FFFFFF");
-    public final static int SCROLL_DIRECTION_DEFAULT = 0;
     public final static String ENV_DEFAULT = "cyberpunk";
     public final static int MSAA_DEFAULT_LEVEL = 1;
     public final static boolean AUDIO_ENABLED = BuildConfig.FLAVOR_backend == "chromium";
@@ -193,7 +199,7 @@ public static WindowSizePreset fromValues(int width, int height) {
     public final static boolean CRASH_REPORTING_DEFAULT = false;
     public final static boolean TELEMETRY_DEFAULT = true;
 
-    private int mCachedScrollDirection = -1;
+    private @ScrollDirection int mCachedScrollDirection = SCROLL_DIRECTION_INVALID;
 
     private boolean mDisableLayers = false;
     public void setDisableLayers(final boolean aDisableLayers) {
@@ -669,9 +675,10 @@ public void setPointerColor(int color) {
         editor.apply();
     }
 
+    @ScrollDirection
     public int getScrollDirection() {
-        if (mCachedScrollDirection < 0) {
-            mCachedScrollDirection = mPrefs.getInt(mContext.getString(R.string.settings_key_scroll_direction), SCROLL_DIRECTION_DEFAULT);
+        if (mCachedScrollDirection == SCROLL_DIRECTION_INVALID) {
+            mCachedScrollDirection = mPrefs.getInt(mContext.getString(R.string.settings_key_scroll_direction), SCROLL_DIRECTION_NATURAL);
         }
         return mCachedScrollDirection;
     }

app/src/common/shared/com/igalia/wolvic/ui/widgets/settings/ControllerOptionsView.java

@@ -93,8 +93,8 @@ private void resetOptions() {
         if (!mBinding.pointerColorRadio.getValueForId(mBinding.pointerColorRadio.getCheckedRadioButtonId()).equals(SettingsStore.POINTER_COLOR_DEFAULT_DEFAULT)) {
             setPointerColor(mBinding.pointerColorRadio.getIdForValue(SettingsStore.POINTER_COLOR_DEFAULT_DEFAULT), true);
         }
-        if (!mBinding.scrollDirectionRadio.getValueForId(mBinding.scrollDirectionRadio.getCheckedRadioButtonId()).equals(SettingsStore.SCROLL_DIRECTION_DEFAULT)) {
-            setScrollDirection(mBinding.scrollDirectionRadio.getIdForValue(SettingsStore.SCROLL_DIRECTION_DEFAULT), true);
+        if (!mBinding.scrollDirectionRadio.getValueForId(mBinding.scrollDirectionRadio.getCheckedRadioButtonId()).equals(SettingsStore.SCROLL_DIRECTION_NATURAL)) {
+            setScrollDirection(mBinding.scrollDirectionRadio.getIdForValue(SettingsStore.SCROLL_DIRECTION_NATURAL), true);
         }
         setSoundEffect(SettingsStore.AUDIO_ENABLED, true);
         setHapticFeedbackEnabled(SettingsStore.HAPTIC_FEEDBACK_ENABLED, true);