Let SliderPreference collect its own preference

Closes #3958

Assisted-by: Claude:claude-opus-5-5

app/src/main/java/eu/kanade/presentation/more/settings/Preference.kt

@@ -49,15 +49,15 @@ sealed class Preference {
          * A [PreferenceItem] that provides a slider to select an integer number.
          */
         data class SliderPreference(
-            val value: Int,
+            val preference: PreferenceData<Int>,
             override val title: String,
             override val subtitle: String? = null,
-            val valueString: String? = null,
+            val valueText: @Composable (Int) -> String = { it.toString() },
             val valueRange: IntProgression = 0..1,
-            @IntRange(from = 0) val steps: Int = with(valueRange) { (last - first) - 1 },
+            @IntRange(from = 0) val steps: Int = with(valueRange) { ((last - first) / step) - 1 },
             override val enabled: Boolean = true,
-            override val onValueChanged: suspend (value: Int) -> Unit = {},
-        ) : PreferenceItem<Int, Unit>() {
+            override val onValueChanged: suspend (value: Int) -> Boolean = { true },
+        ) : PreferenceItem<Int, Boolean>() {
             override val icon: ImageVector? = null
         }
 

app/src/main/java/eu/kanade/presentation/more/settings/PreferenceItem.kt

@@ -88,16 +88,19 @@ internal fun PreferenceItem(
                 )
             }
             is Preference.PreferenceItem.SliderPreference -> {
+                val value by item.preference.collectAsState()
                 BaseSliderItem(
-                    value = item.value,
+                    value = value,
                     valueRange = item.valueRange,
                     steps = item.steps,
                     title = item.title,
                     subtitle = item.subtitle,
-                    valueString = item.valueString.takeUnless { it.isNullOrEmpty() } ?: item.value.toString(),
-                    onChange = {
+                    valueString = item.valueText(value),
+                    onChange = { newValue ->
                         scope.launch {
-                            item.onValueChanged(it)
+                            if (item.onValueChanged(newValue)) {
+                                item.preference.set(newValue)
+                            }
                         }
                     },
                     titleStyle = MaterialTheme.typography.titleLarge.copy(fontSize = TitleFontSize),

app/src/main/java/eu/kanade/presentation/more/settings/screen/SettingsDownloadScreen.kt

@@ -34,8 +34,6 @@ object SettingsDownloadScreen : SearchableSettings {
         val allCategories by getCategories.subscribe().collectAsState(initial = emptyList())
 
         val downloadPreferences = remember { context.appGraph.downloadPreferences }
-        val parallelSourceLimit by downloadPreferences.parallelSourceLimit.collectAsState()
-        val parallelPageLimit by downloadPreferences.parallelPageLimit.collectAsState()
         return listOf(
             Preference.PreferenceItem.SwitchPreference(
                 preference = downloadPreferences.downloadOnlyOverWifi,
@@ -51,17 +49,15 @@ object SettingsDownloadScreen : SearchableSettings {
                 subtitle = stringResource(MR.strings.split_tall_images_summary),
             ),
             Preference.PreferenceItem.SliderPreference(
-                value = parallelSourceLimit,
+                preference = downloadPreferences.parallelSourceLimit,
                 valueRange = 1..10,
                 title = stringResource(MR.strings.pref_download_concurrent_sources),
-                onValueChanged = { downloadPreferences.parallelSourceLimit.set(it) },
             ),
             Preference.PreferenceItem.SliderPreference(
-                value = parallelPageLimit,
+                preference = downloadPreferences.parallelPageLimit,
                 valueRange = 1..15,
                 title = stringResource(MR.strings.pref_download_concurrent_pages),
                 subtitle = stringResource(MR.strings.pref_download_concurrent_pages_summary),
-                onValueChanged = { downloadPreferences.parallelPageLimit.set(it) },
             ),
             getDeleteChaptersGroup(
                 downloadPreferences = downloadPreferences,

app/src/main/java/eu/kanade/presentation/more/settings/screen/SettingsReaderScreen.kt

@@ -116,12 +116,6 @@ object SettingsReaderScreen : SearchableSettings {
     private fun getEInkGroup(readerPreferences: ReaderPreferences): Preference.PreferenceGroup {
         val flashPageState by readerPreferences.flashOnPageChange.collectAsState()
 
-        val flashMillisPref = readerPreferences.flashDurationMillis
-        val flashMillis by flashMillisPref.collectAsState()
-
-        val flashIntervalPref = readerPreferences.flashPageInterval
-        val flashInterval by flashIntervalPref.collectAsState()
-
         val flashColorPref = readerPreferences.flashColor
 
         return Preference.PreferenceGroup(
@@ -133,20 +127,18 @@ object SettingsReaderScreen : SearchableSettings {
                     subtitle = stringResource(MR.strings.pref_flash_page_summ),
                 ),
                 Preference.PreferenceItem.SliderPreference(
-                    value = flashMillis / ReaderPreferences.MILLI_CONVERSION,
-                    valueRange = 1..15,
+                    preference = readerPreferences.flashDurationMillis,
+                    valueRange = ReaderPreferences.MILLI_CONVERSION.let { it..it * 15 step it },
                     title = stringResource(MR.strings.pref_flash_duration),
-                    valueString = stringResource(MR.strings.pref_flash_duration_summary, flashMillis),
+                    valueText = { stringResource(MR.strings.pref_flash_duration_summary, it) },
                     enabled = flashPageState,
-                    onValueChanged = { flashMillisPref.set(it * ReaderPreferences.MILLI_CONVERSION) },
                 ),
                 Preference.PreferenceItem.SliderPreference(
-                    value = flashInterval,
+                    preference = readerPreferences.flashPageInterval,
                     valueRange = 1..10,
                     title = stringResource(MR.strings.pref_flash_page_interval),
-                    valueString = pluralStringResource(MR.plurals.pref_pages, flashInterval, flashInterval),
+                    valueText = { pluralStringResource(MR.plurals.pref_pages, it, it) },
                     enabled = flashPageState,
-                    onValueChanged = { flashIntervalPref.set(it) },
                 ),
                 Preference.PreferenceItem.ListPreference(
                     preference = flashColorPref,
@@ -288,12 +280,10 @@ object SettingsReaderScreen : SearchableSettings {
         val navModePref = readerPreferences.navigationModeWebtoon
         val dualPageSplitPref = readerPreferences.dualPageSplitWebtoon
         val rotateToFitPref = readerPreferences.dualPageRotateToFitWebtoon
-        val webtoonSidePaddingPref = readerPreferences.webtoonSidePadding
 
         val navMode by navModePref.collectAsState()
         val dualPageSplit by dualPageSplitPref.collectAsState()
         val rotateToFit by rotateToFitPref.collectAsState()
-        val webtoonSidePadding by webtoonSidePaddingPref.collectAsState()
 
         return Preference.PreferenceGroup(
             title = stringResource(MR.strings.webtoon_viewer),
@@ -318,13 +308,12 @@ object SettingsReaderScreen : SearchableSettings {
                     enabled = navMode != 5,
                 ),
                 Preference.PreferenceItem.SliderPreference(
-                    value = webtoonSidePadding,
+                    preference = readerPreferences.webtoonSidePadding,
                     valueRange = ReaderPreferences.let {
                         it.WEBTOON_PADDING_MIN..it.WEBTOON_PADDING_MAX
                     },
                     title = stringResource(MR.strings.pref_webtoon_side_padding),
-                    valueString = numberFormat.format(webtoonSidePadding / 100f),
-                    onValueChanged = { webtoonSidePaddingPref.set(it) },
+                    valueText = { numberFormat.format(it / 100f) },
                 ),
                 Preference.PreferenceItem.ListPreference(
                     preference = readerPreferences.readerHideThreshold,
@@ -385,8 +374,6 @@ object SettingsReaderScreen : SearchableSettings {
         val readWithVolumeKeys by readWithVolumeKeysPref.collectAsState()
 
         val verticalNavigator by readerPreferences.verticalNavigator.collectAsState()
-        val verticalNavigatorHeightPref = readerPreferences.verticalNavigatorHeight
-        val verticalNavigatorHeight by verticalNavigatorHeightPref.collectAsState()
 
         return Preference.PreferenceGroup(
             title = stringResource(MR.strings.pref_reader_navigation),
@@ -412,11 +399,10 @@ object SettingsReaderScreen : SearchableSettings {
                     enabled = verticalNavigator.isNotEmpty(),
                 ),
                 Preference.PreferenceItem.SliderPreference(
-                    value = verticalNavigatorHeight,
+                    preference = readerPreferences.verticalNavigatorHeight,
                     valueRange = 65..100,
                     steps = 6,
                     title = stringResource(MR.strings.pref_vertical_navigator_height),
-                    onValueChanged = { verticalNavigatorHeightPref.set(it) },
                     enabled = verticalNavigator.isNotEmpty(),
                 ),
             ),