feat: pure black theme for AMOLED screens (#99)

app/src/main/java/de/jeanlucmakiola/agendula/MainActivity.kt

@@ -28,7 +28,6 @@ import de.jeanlucmakiola.agendula.data.di.LaunchHook
 import de.jeanlucmakiola.agendula.domain.SmartList
 import de.jeanlucmakiola.agendula.ui.imports.importIntentUri
 import de.jeanlucmakiola.agendula.ui.navigation.AppShortcuts
-import de.jeanlucmakiola.agendula.data.prefs.ThemeMode
 import de.jeanlucmakiola.agendula.ui.RootScreen
 import de.jeanlucmakiola.agendula.ui.crash.CrashReportActivity
 import de.jeanlucmakiola.agendula.ui.navigation.NavRequest
@@ -88,15 +87,15 @@ class MainActivity : ComponentActivity() {
         setContent {
             val settingsViewModel: SettingsViewModel = hiltViewModel()
             val ui by settingsViewModel.state.collectAsStateWithLifecycle()
-            val darkTheme = when (ui.settings.themeMode) {
-                ThemeMode.SYSTEM -> isSystemInDarkTheme()
-                ThemeMode.LIGHT -> false
-                ThemeMode.DARK -> true
-            }
+            val darkTheme = ui.settings.themeMode.isDark(isSystemInDarkTheme())
             val context = LocalContext.current
             val use24Hour = ui.settings.timeFormat.is24Hour(DateFormat.is24HourFormat(context))
             val firstDayOfWeek = ui.settings.weekStart ?: localeFirstDayOfWeek()
-            AgendulaTheme(darkTheme = darkTheme, dynamicColor = ui.settings.dynamicColor) {
+            AgendulaTheme(
+                darkTheme = darkTheme,
+                dynamicColor = ui.settings.dynamicColor,
+                pureBlack = ui.settings.themeMode.isPureBlack,
+            ) {
                 CompositionLocalProvider(
                     LocalUse24HourFormat provides use24Hour,
                     LocalFirstDayOfWeek provides firstDayOfWeek,

app/src/main/java/de/jeanlucmakiola/agendula/data/prefs/SettingsPrefs.kt

@@ -31,7 +31,18 @@ import kotlinx.coroutines.flow.map
 import javax.inject.Inject
 import javax.inject.Singleton
 
-enum class ThemeMode { SYSTEM, LIGHT, DARK }
+/** [BLACK] is dark with pure-black surfaces, for AMOLED screens. */
+enum class ThemeMode {
+    SYSTEM, LIGHT, DARK, BLACK;
+
+    fun isDark(systemDark: Boolean): Boolean = when (this) {
+        SYSTEM -> systemDark
+        LIGHT -> false
+        DARK, BLACK -> true
+    }
+
+    val isPureBlack: Boolean get() = this == BLACK
+}
 
 /** Clock convention: AUTO follows the device's 24-hour switch. */
 enum class TimeFormatPref { AUTO, TWELVE_HOUR, TWENTY_FOUR_HOUR }

app/src/main/java/de/jeanlucmakiola/agendula/ui/settings/AppearanceScreen.kt

@@ -140,6 +140,7 @@ internal fun AppearanceScreen(
             options = ThemeMode.entries,
             selected = state.settings.themeMode,
             label = { stringResource(themeLabel(it)) },
+            summary = { if (it == ThemeMode.BLACK) stringResource(R.string.settings_theme_black_summary) else null },
             onSelect = viewModel::setThemeMode,
             onDismiss = { showTheme = false },
         )
@@ -167,4 +168,5 @@ private fun themeLabel(mode: ThemeMode): Int = when (mode) {
     ThemeMode.SYSTEM -> R.string.settings_theme_system
     ThemeMode.LIGHT -> R.string.settings_theme_light
     ThemeMode.DARK -> R.string.settings_theme_dark
+    ThemeMode.BLACK -> R.string.settings_theme_black
 }

app/src/main/java/de/jeanlucmakiola/agendula/ui/theme/Theme.kt

@@ -15,6 +15,7 @@ import de.jeanlucmakiola.floret.identity.FloretExpressiveTheme
 fun AgendulaTheme(
     darkTheme: Boolean = isSystemInDarkTheme(),
     dynamicColor: Boolean = true,
+    pureBlack: Boolean = false,
     content: @Composable () -> Unit,
 ) {
     FloretExpressiveTheme(
@@ -22,6 +23,7 @@ fun AgendulaTheme(
         darkScheme = AgendulaDarkFallback,
         darkTheme = darkTheme,
         dynamicColor = dynamicColor,
+        pureBlack = pureBlack,
         typography = AgendulaTypography,
         content = content,
     )

app/src/main/java/de/jeanlucmakiola/agendula/widget/TaskWidgetConfigActivity.kt

@@ -39,7 +39,6 @@ import dagger.hilt.android.AndroidEntryPoint
 import de.jeanlucmakiola.agendula.R
 import de.jeanlucmakiola.agendula.data.prefs.Settings
 import de.jeanlucmakiola.agendula.data.prefs.SettingsPrefs
-import de.jeanlucmakiola.agendula.data.prefs.ThemeMode
 import de.jeanlucmakiola.agendula.data.tasks.TasksRepository
 import de.jeanlucmakiola.agendula.domain.SavedFilter
 import de.jeanlucmakiola.agendula.domain.SmartList
@@ -135,12 +134,12 @@ class TaskWidgetConfigActivity : ComponentActivity() {
                 rowColor = parseWidgetRowColor(state[WIDGET_ROW_COLOR_KEY])
                 selectedListIds = parseWidgetListIds(state[WIDGET_LIST_IDS_KEY])
             }
-            val dark = when (settings.themeMode) {
-                ThemeMode.SYSTEM -> isSystemInDarkTheme()
-                ThemeMode.LIGHT -> false
-                ThemeMode.DARK -> true
-            }
-            AgendulaTheme(darkTheme = dark, dynamicColor = settings.dynamicColor) {
+            val dark = settings.themeMode.isDark(isSystemInDarkTheme())
+            AgendulaTheme(
+                darkTheme = dark,
+                dynamicColor = settings.dynamicColor,
+                pureBlack = settings.themeMode.isPureBlack,
+            ) {
                 Surface(modifier = Modifier.fillMaxSize(), color = MaterialTheme.colorScheme.surface) {}
                 WidgetFilterPicker(
                     kind = kind,

app/src/main/java/de/jeanlucmakiola/agendula/widget/WidgetData.kt

@@ -82,7 +82,7 @@ internal fun effectiveThemeMode(appThemeMode: ThemeMode, override: WidgetThemeMo
     override ?: when (appThemeMode) {
         ThemeMode.SYSTEM -> WidgetThemeMode.SYSTEM
         ThemeMode.LIGHT -> WidgetThemeMode.LIGHT
-        ThemeMode.DARK -> WidgetThemeMode.DARK
+        ThemeMode.DARK, ThemeMode.BLACK -> WidgetThemeMode.DARK
     }
 
 /** The smart lists a widget can show, in picker order. */

app/src/main/res/values/strings.xml

@@ -448,6 +448,8 @@
     <string name="settings_theme_system">Follow system</string>
     <string name="settings_theme_light">Light</string>
     <string name="settings_theme_dark">Dark</string>
+    <string name="settings_theme_black">Black</string>
+    <string name="settings_theme_black_summary">Dark with pure black backgrounds, for AMOLED screens</string>
     <string name="settings_dynamic_color">Dynamic colour</string>
     <string name="settings_dynamic_color_hint">Use colours from your wallpaper</string>
     <string name="settings_section_reminders">Notifications</string>

app/src/test/java/de/jeanlucmakiola/agendula/widget/WidgetDataTest.kt

@@ -210,6 +210,7 @@ class WidgetDataTest {
     fun `no override resolves to whatever the app's own theme means`() {
         assertThat(readyWithTheme(ThemeMode.DARK).effectiveThemeMode(null)).isEqualTo(WidgetThemeMode.DARK)
         assertThat(readyWithTheme(ThemeMode.SYSTEM).effectiveThemeMode(null)).isEqualTo(WidgetThemeMode.SYSTEM)
+        assertThat(readyWithTheme(ThemeMode.BLACK).effectiveThemeMode(null)).isEqualTo(WidgetThemeMode.DARK)
     }
 
     @Test