Singleton Navigation

app/src/main/kotlin/com/hippo/ehviewer/ui/reader/GalleryPager.kt

@@ -61,8 +61,7 @@ fun GalleryPager(
         } else {
             onNavigationModeChange()
         }
-        navigation.invertMode = TappingInvertMode.entries[invertMode]
-        navigation.regions
+        navigation.regions(TappingInvertMode.entries[invertMode])
     }
     val navigator by rememberUpdatedState(regions)
     if (isPagerType) {

app/src/main/kotlin/eu/kanade/tachiyomi/ui/reader/viewer/ViewerNavigation.kt

@@ -12,7 +12,6 @@ import eu.kanade.tachiyomi.ui.reader.viewer.navigation.RightAndLeftNavigation
 import eu.kanade.tachiyomi.util.lang.invert
 
 abstract class ViewerNavigation {
-
     sealed class NavigationRegion(@StringRes val nameRes: Int, val colorRes: Int) {
         data object MENU : NavigationRegion(R.string.action_menu, R.color.navigation_menu)
         data object PREV : NavigationRegion(R.string.nav_zone_prev, R.color.navigation_prev)
@@ -21,32 +20,25 @@ abstract class ViewerNavigation {
         data object RIGHT : NavigationRegion(R.string.nav_zone_right, R.color.navigation_right)
     }
 
-    data class Region(
-        val rectF: RectF,
-        val type: NavigationRegion,
-    ) {
+    data class Region(val rectF: RectF, val type: NavigationRegion) {
         fun invert(invertMode: TappingInvertMode): Region {
             if (invertMode == TappingInvertMode.NONE) return this
-            return this.copy(
-                rectF = this.rectF.invert(invertMode),
-            )
+            return this.copy(rectF = rectF.invert(invertMode))
         }
     }
 
     protected abstract val originalRegions: List<Region>
 
-    val regions get() = originalRegions.map { it.invert(invertMode) }
-
-    var invertMode = TappingInvertMode.NONE
+    fun regions(invertMode: TappingInvertMode = TappingInvertMode.NONE) = originalRegions.map { it.invert(invertMode) }
 
     companion object {
         fun fromPreference(value: Int, isVertical: Boolean) = when (value) {
-            1 -> LNavigation()
-            2 -> KindlishNavigation()
-            3 -> EdgeNavigation()
-            4 -> RightAndLeftNavigation()
-            5 -> DisabledNavigation()
-            else -> if (isVertical) LNavigation() else RightAndLeftNavigation()
+            1 -> LNavigation
+            2 -> KindlishNavigation
+            3 -> EdgeNavigation
+            4 -> RightAndLeftNavigation
+            5 -> DisabledNavigation
+            else -> if (isVertical) LNavigation else RightAndLeftNavigation
         }
     }
 }

app/src/main/kotlin/eu/kanade/tachiyomi/ui/reader/viewer/navigation/DisabledNavigation.kt

@@ -12,7 +12,6 @@ import eu.kanade.tachiyomi.ui.reader.viewer.ViewerNavigation
  * | M | M | M |   N: Next
  * +---+---+---+
 */
-class DisabledNavigation : ViewerNavigation() {
-
-    override val originalRegions: List<Region> = emptyList()
+object DisabledNavigation : ViewerNavigation() {
+    override val originalRegions = emptyList<Region>()
 }

app/src/main/kotlin/eu/kanade/tachiyomi/ui/reader/viewer/navigation/EdgeNavigation.kt

@@ -13,9 +13,8 @@ import eu.kanade.tachiyomi.ui.reader.viewer.ViewerNavigation
  * | N | P | N |   N: Next
  * +---+---+---+
 */
-class EdgeNavigation : ViewerNavigation() {
-
-    override val originalRegions: List<Region> = listOf(
+object EdgeNavigation : ViewerNavigation() {
+    override val originalRegions = listOf(
         Region(
             rectF = RectF(0f, 0f, 0.33f, 1f),
             type = NavigationRegion.NEXT,

app/src/main/kotlin/eu/kanade/tachiyomi/ui/reader/viewer/navigation/KindlishNavigation.kt

@@ -13,9 +13,8 @@ import eu.kanade.tachiyomi.ui.reader.viewer.ViewerNavigation
  * | P | N | N |   N: Next
  * +---+---+---+
 */
-class KindlishNavigation : ViewerNavigation() {
-
-    override val originalRegions: List<Region> = listOf(
+object KindlishNavigation : ViewerNavigation() {
+    override val originalRegions = listOf(
         Region(
             rectF = RectF(0.33f, 0.33f, 1f, 1f),
             type = NavigationRegion.NEXT,

app/src/main/kotlin/eu/kanade/tachiyomi/ui/reader/viewer/navigation/LNavigation.kt

@@ -13,9 +13,8 @@ import eu.kanade.tachiyomi.ui.reader.viewer.ViewerNavigation
  * | N | N | N |   N: Next
  * +---+---+---+
  */
-open class LNavigation : ViewerNavigation() {
-
-    override val originalRegions: List<Region> = listOf(
+object LNavigation : ViewerNavigation() {
+    override val originalRegions = listOf(
         Region(
             rectF = RectF(0f, 0.33f, 0.33f, 0.66f),
             type = NavigationRegion.PREV,

app/src/main/kotlin/eu/kanade/tachiyomi/ui/reader/viewer/navigation/RightAndLeftNavigation.kt

@@ -13,9 +13,8 @@ import eu.kanade.tachiyomi.ui.reader.viewer.ViewerNavigation
  * | N | M | P |   N: Move Left
  * +---+---+---+
  */
-class RightAndLeftNavigation : ViewerNavigation() {
-
-    override val originalRegions: List<Region> = listOf(
+object RightAndLeftNavigation : ViewerNavigation() {
+    override val originalRegions = listOf(
         Region(
             rectF = RectF(0f, 0f, 0.33f, 1f),
             type = NavigationRegion.LEFT,