feat(settings): add option for different themes

composeApp/src/androidMain/kotlin/io/anthonyberg/veganenumbers/MainActivity.kt

@@ -4,8 +4,10 @@ import App
 import android.os.Bundle
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
+import androidx.compose.foundation.isSystemInDarkTheme
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.tooling.preview.Preview
+import data.SettingsVar
 import io.anthonyberg.veganenumbers.ui.theme.AppTheme
 
 class MainActivity : ComponentActivity() {
@@ -13,7 +15,13 @@ class MainActivity : ComponentActivity() {
         super.onCreate(savedInstanceState)
 
         setContent {
-            AppTheme {
+            AppTheme(
+                darkTheme = when(SettingsVar.theme.value) {
+                    1 -> false
+                    2 -> true
+                    else -> isSystemInDarkTheme()
+                }
+            ) {
                 App()
             }
         }

composeApp/src/commonMain/kotlin/data/SettingsVar.kt

@@ -0,0 +1,7 @@
+package data
+
+import androidx.compose.runtime.mutableIntStateOf
+
+object SettingsVar {
+    val theme = mutableIntStateOf(0)
+}

composeApp/src/commonMain/kotlin/tab/setting/Settings.kt

@@ -1,16 +1,22 @@
 package tab.setting
 
 import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.padding
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.filled.ArrowBack
 import androidx.compose.material3.*
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.saveable.rememberSaveable
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.input.nestedscroll.nestedScroll
 import cafe.adriel.voyager.core.screen.Screen
 import cafe.adriel.voyager.navigator.LocalNavigator
 import cafe.adriel.voyager.navigator.currentOrThrow
+import data.SettingsVar
 
 object Settings : Screen {
 
@@ -42,7 +48,33 @@ object Settings : Screen {
 
     @Composable
     private fun SettingsContent() {
-        Text("Theme")
+        Theme()
         Text("List Style")
     }
+
+    /**
+     * ALl the different themes that can be picked
+     * - 0 - Auto
+     * - 1 - Light
+     * - 2 - Dark
+     */
+    @Composable
+    private fun Theme() {
+        var mode by rememberSaveable { SettingsVar.theme }
+        val themes = listOf("Auto", "Light", "Dark")
+
+        Text("Theme")
+
+        for ((index, value) in themes.withIndex()) {
+            Row(
+                verticalAlignment = Alignment.CenterVertically,
+            ) {
+                RadioButton(
+                    selected = mode == index,
+                    onClick = { mode = index }
+                )
+                Text(value)
+            }
+        }
+    }
 }