Interactive formatting settings

core/base/src/main/java/com/sadellie/unitto/core/base/Precision.kt

@@ -22,28 +22,3 @@ package com.sadellie.unitto.core.base
  * Current maximum scale that will be used in app. Used in various place in code
  */
 const val MAX_PRECISION: Int = 1_000
-
-/**
- * Currently available scale options
- */
-val PRECISIONS: Map<Int, Int> by lazy {
-    mapOf(
-        0 to R.string.precision_zero,
-        1 to R.string.precision_one,
-        2 to R.string.precision_two,
-        3 to R.string.precision_three,
-        4 to R.string.precision_four,
-        5 to R.string.precision_five,
-        6 to R.string.precision_six,
-        7 to R.string.precision_seven,
-        8 to R.string.precision_eight,
-        9 to R.string.precision_nine,
-        10 to R.string.precision_ten,
-        11 to R.string.precision_eleven,
-        12 to R.string.precision_twelve,
-        13 to R.string.precision_thirteen,
-        14 to R.string.precision_fourteen,
-        15 to R.string.precision_fifteen,
-        MAX_PRECISION to R.string.max_precision
-    )
-}

core/base/src/main/res/values/strings.xml

@@ -1258,6 +1258,7 @@
     <string name="third_party_licenses">Third party licenses</string>
     <string name="rate_this_app">Rate this app</string>
     <string name="formatting_settings_group">Formatting</string>
+    <string name="formatting_settings_support">Precision and numbers appearance</string>
     <string name="additional_settings_group">Additional</string>
 
     <!--Tools-->
@@ -1306,9 +1307,9 @@
 
     <!--Separator-->
     <string name="separator_setting_support">Group separator symbol</string>
-    <string name="period">Period (42.069,12)</string>
+    <string name="period">Period</string>
-    <string name="comma">Comma (42,069.12)</string>
+    <string name="comma">Comma</string>
-    <string name="spaces">Spaces (42 069.12)</string>
+    <string name="spaces">Spaces</string>
 
     <!--Output format-->
     <string name="output_format_setting_support">Result value formatting</string>

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/SegmentedButton.kt

@@ -66,7 +66,7 @@ fun RowScope.SegmentedButton(
     label: String,
     onClick: () -> Unit,
     selected: Boolean,
-    icon: ImageVector
+    icon: ImageVector? = null
 ) {
     val containerColor =
         if (selected) MaterialTheme.colorScheme.secondaryContainer else MaterialTheme.colorScheme.surface
@@ -81,14 +81,16 @@ fun RowScope.SegmentedButton(
         ),
         contentPadding = PaddingValues(horizontal = 12.dp)
     ) {
-        Crossfade(targetState = selected) {
+        if (icon != null) {
-            if (it) {
+            Crossfade(targetState = selected) {
-                Icon(Icons.Default.Check, null, Modifier.size(18.dp))
+                if (it) {
-            } else {
+                    Icon(Icons.Default.Check, null, Modifier.size(18.dp))
-                Icon(icon, null, Modifier.size(18.dp))
+                } else {
+                    Icon(icon, null, Modifier.size(18.dp))
+                }
             }
+            Spacer(Modifier.width(8.dp))
         }
-        Spacer(Modifier.width(8.dp))
         Text(label)
     }
 }

core/ui/src/main/java/com/sadellie/unitto/core/ui/common/UnittoSlider.kt

@@ -0,0 +1,157 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.core.ui.common
+
+import androidx.compose.animation.core.animateFloatAsState
+import androidx.compose.animation.core.spring
+import androidx.compose.foundation.Canvas
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Slider
+import androidx.compose.material3.SliderPositions
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.graphics.ClipOp
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.Path
+import androidx.compose.ui.graphics.StrokeCap
+import androidx.compose.ui.graphics.drawscope.Stroke
+import androidx.compose.ui.graphics.drawscope.clipRect
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.unit.dp
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.launch
+import kotlin.math.ceil
+import kotlin.math.roundToInt
+
+@Composable
+fun UnittoSlider(
+    modifier: Modifier = Modifier,
+    value: Float,
+    valueRange: ClosedFloatingPointRange<Float>,
+    onValueChange: (Float) -> Unit,
+    onValueChangeFinished: (Float) -> Unit = {}
+) {
+    val animated = animateFloatAsState(targetValue = value)
+
+    Slider(
+        value = animated.value,
+        onValueChange = onValueChange,
+        modifier = modifier,
+        valueRange = valueRange,
+        onValueChangeFinished = { onValueChangeFinished(animated.value) },
+        track = { sliderPosition -> SquigglyTrack(sliderPosition) },
+        steps = valueRange.endInclusive.roundToInt(),
+    )
+}
+
+@Composable
+private fun SquigglyTrack(
+    sliderPosition: SliderPositions,
+    eachWaveWidth: Float = 80f,
+    strokeWidth: Float = 15f,
+    filledColor: Color = MaterialTheme.colorScheme.primary,
+    unfilledColor: Color = MaterialTheme.colorScheme.surfaceVariant
+) {
+    val coroutineScope = rememberCoroutineScope()
+    var direct by remember { mutableStateOf(1f) }
+    val animatedDirect = animateFloatAsState(direct, spring())
+    val slider = sliderPosition.activeRange.endInclusive
+
+    LaunchedEffect(sliderPosition.activeRange.endInclusive) {
+        coroutineScope.launch {
+            delay(300L)
+            direct = if (direct == 1f) -1f else 1f
+        }
+    }
+
+    Canvas(
+        modifier = Modifier
+            .fillMaxWidth()
+            .height(20.dp)
+    ) {
+        val width = size.width
+        val height = size.height
+
+        val path = Path().apply {
+            moveTo(
+                x = strokeWidth / 2,
+                y = height.times(0.5f)
+            )
+            val amount = ceil(width.div(eachWaveWidth))
+
+            repeat(amount.toInt()) {
+                val peek = if (it % 2 == 0) animatedDirect.value else -animatedDirect.value
+
+                relativeQuadraticBezierTo(
+                    dx1 = eachWaveWidth * 0.5f,
+                    // 0.75, because 1.0 was clipping out of bound for some reason
+                    dy1 = height.times(0.75f) * peek,
+                    dx2 = eachWaveWidth,
+                    dy2 = 0f
+                )
+            }
+        }
+
+        clipRect(
+            top = 0f,
+            left = 0f,
+            right = width.times(slider),
+            bottom = height,
+            clipOp = ClipOp.Intersect
+        ) {
+            drawPath(
+                path = path,
+                color = filledColor,
+                style = Stroke(strokeWidth, cap = StrokeCap.Round)
+            )
+        }
+
+        drawLine(
+            color = unfilledColor,
+            start = Offset(width.times(slider), height.times(0.5f)),
+            end = Offset(width, height.times(0.5f)),
+            strokeWidth = strokeWidth,
+            cap = StrokeCap.Round
+        )
+    }
+}
+
+@Preview(device = "spec:width=411dp,height=891dp")
+@Preview(device = "spec:width=673.5dp,height=841dp,dpi=480")
+@Preview(device = "spec:width=1280dp,height=800dp,dpi=480")
+@Preview(device = "spec:width=1920dp,height=1080dp,dpi=480")
+@Composable
+private fun PreviewNewSlider() {
+    var currentValue by remember { mutableStateOf(0.9f) }
+
+    UnittoSlider(
+        value = currentValue,
+        valueRange = 0f..1f,
+        onValueChange = { currentValue = it }
+    )
+}

feature/settings/build.gradle.kts

@@ -31,6 +31,7 @@ dependencies {
     implementation(libs.com.github.sadellie.themmo)
     implementation(libs.org.burnoutcrew.composereorderable)
 
+    implementation(project(mapOf("path" to ":data:common")))
     implementation(project(mapOf("path" to ":data:model")))
     implementation(project(mapOf("path" to ":data:unitgroups")))
     implementation(project(mapOf("path" to ":data:userprefs")))

feature/settings/src/main/java/com/sadellie/unitto/feature/settings/SettingsScreen.kt

@@ -19,7 +19,6 @@
 package com.sadellie.unitto.feature.settings
 
 import androidx.compose.foundation.clickable
-import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.Home
@@ -42,14 +41,10 @@ import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.res.stringResource
-import androidx.compose.ui.unit.dp
 import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import com.sadellie.unitto.core.base.BuildConfig
-import com.sadellie.unitto.core.base.OUTPUT_FORMAT
-import com.sadellie.unitto.core.base.PRECISIONS
 import com.sadellie.unitto.core.base.R
-import com.sadellie.unitto.core.base.SEPARATORS
 import com.sadellie.unitto.core.base.TOP_LEVEL_DESTINATIONS
 import com.sadellie.unitto.core.ui.common.Header
 import com.sadellie.unitto.core.ui.common.MenuButton
@@ -59,6 +54,7 @@ import com.sadellie.unitto.core.ui.openLink
 import com.sadellie.unitto.data.model.UnitsListSorting
 import com.sadellie.unitto.feature.settings.components.AlertDialogWithList
 import com.sadellie.unitto.feature.settings.navigation.aboutRoute
+import com.sadellie.unitto.feature.settings.navigation.formattingRoute
 import com.sadellie.unitto.feature.settings.navigation.themesRoute
 import com.sadellie.unitto.feature.settings.navigation.unitsGroupRoute
 
@@ -110,43 +106,18 @@ internal fun SettingsScreen(
                 )
             }
 
-            // GENERAL GROUP
+            // FORMATTING
-            item { Header(stringResource(R.string.formatting_settings_group)) }
-
-            // PRECISION
             item {
                 ListItem(
                     leadingContent = {
                         Icon(
                             Icons.Default._123,
-                            stringResource(R.string.precision_setting),
+                            stringResource(R.string.formatting_settings_group),
                         )
                     },
-                    headlineContent = { Text(stringResource(R.string.precision_setting)) },
+                    headlineContent = { Text(stringResource(R.string.formatting_settings_group)) },
-                    supportingContent = { Text(stringResource(R.string.precision_setting_support)) },
+                    supportingContent = { Text(stringResource(R.string.formatting_settings_support)) },
-                    modifier = Modifier.clickable { dialogState = DialogState.PRECISION }
+                    modifier = Modifier.clickable { navControllerAction(formattingRoute) }
-                )
-            }
-
-            // SEPARATOR
-            item {
-                ListItem(
-                    headlineContent = { Text(stringResource(R.string.separator_setting)) },
-                    supportingContent = { Text(stringResource(R.string.separator_setting_support)) },
-                    modifier = Modifier
-                        .clickable { dialogState = DialogState.SEPARATOR }
-                        .padding(start = 40.dp)
-                )
-            }
-
-            // OUTPUT FORMAT
-            item {
-                ListItem(
-                    headlineContent = { Text(stringResource(R.string.output_format_setting)) },
-                    supportingContent = { Text(stringResource(R.string.output_format_setting_support)) },
-                    modifier = Modifier
-                        .clickable { dialogState = DialogState.OUTPUT_FORMAT }
-                        .padding(start = 40.dp)
                 )
             }
 
@@ -260,35 +231,6 @@ internal fun SettingsScreen(
 
     // Showing dialog
     when (dialogState) {
-        DialogState.PRECISION -> {
-            AlertDialogWithList(
-                title = stringResource(R.string.precision_setting),
-                listItems = PRECISIONS,
-                selectedItemIndex = userPrefs.value.digitsPrecision,
-                selectAction = viewModel::updatePrecision,
-                dismissAction = { resetDialog() },
-                supportText = stringResource(R.string.precision_setting_info)
-            )
-        }
-        DialogState.SEPARATOR -> {
-            AlertDialogWithList(
-                title = stringResource(R.string.separator_setting),
-                listItems = SEPARATORS,
-                selectedItemIndex = userPrefs.value.separator,
-                selectAction = viewModel::updateSeparator,
-                dismissAction = { resetDialog() }
-            )
-        }
-        DialogState.OUTPUT_FORMAT -> {
-            AlertDialogWithList(
-                title = stringResource(R.string.output_format_setting),
-                listItems = OUTPUT_FORMAT,
-                selectedItemIndex = userPrefs.value.outputFormat,
-                selectAction = viewModel::updateOutputFormat,
-                dismissAction = { resetDialog() },
-                supportText = stringResource(R.string.output_format_setting_info)
-            )
-        }
         DialogState.START_SCREEN -> {
             AlertDialogWithList(
                 title = stringResource(R.string.starting_screen_setting),
@@ -321,5 +263,5 @@ internal fun SettingsScreen(
  * All possible states for alert dialog that opens when user clicks on settings.
  */
 private enum class DialogState {
-    NONE, PRECISION, SEPARATOR, OUTPUT_FORMAT, START_SCREEN, UNIT_LIST_SORTING
+    NONE, START_SCREEN, UNIT_LIST_SORTING
 }

feature/settings/src/main/java/com/sadellie/unitto/feature/settings/SettingsViewModel.kt

@@ -40,33 +40,6 @@ class SettingsViewModel @Inject constructor(
             UserPreferences()
         )
 
-    /**
-     * @see UserPreferencesRepository.updateDigitsPrecision
-     */
-    fun updatePrecision(precision: Int) {
-        viewModelScope.launch {
-            userPrefsRepository.updateDigitsPrecision(precision)
-        }
-    }
-
-    /**
-     * @see UserPreferencesRepository.updateSeparator
-     */
-    fun updateSeparator(separator: Int) {
-        viewModelScope.launch {
-            userPrefsRepository.updateSeparator(separator)
-        }
-    }
-
-    /**
-     * @see UserPreferencesRepository.updateOutputFormat
-     */
-    fun updateOutputFormat(outputFormat: Int) {
-        viewModelScope.launch {
-            userPrefsRepository.updateOutputFormat(outputFormat)
-        }
-    }
-
     /**
      * @see UserPreferencesRepository.updateVibrations
      */

feature/settings/src/main/java/com/sadellie/unitto/feature/settings/formatting/FormattingScreen.kt

@@ -0,0 +1,242 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.feature.settings.formatting
+
+import androidx.compose.foundation.background
+import androidx.compose.foundation.horizontalScroll
+import androidx.compose.foundation.interaction.MutableInteractionSource
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.wrapContentWidth
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Architecture
+import androidx.compose.material.icons.filled.EMobiledata
+import androidx.compose.material.icons.filled._123
+import androidx.compose.material3.Icon
+import androidx.compose.material3.ListItem
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.unit.dp
+import androidx.hilt.navigation.compose.hiltViewModel
+import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import com.sadellie.unitto.core.base.OUTPUT_FORMAT
+import com.sadellie.unitto.core.base.OutputFormat
+import com.sadellie.unitto.core.base.R
+import com.sadellie.unitto.core.base.SEPARATORS
+import com.sadellie.unitto.core.base.Separator
+import com.sadellie.unitto.core.ui.common.NavigateUpButton
+import com.sadellie.unitto.core.ui.common.UnittoSlider
+import com.sadellie.unitto.core.ui.common.SegmentedButton
+import com.sadellie.unitto.core.ui.common.SegmentedButtonsRow
+import com.sadellie.unitto.core.ui.common.UnittoScreenWithLargeTopBar
+import com.sadellie.unitto.core.ui.common.squashable
+import com.sadellie.unitto.core.ui.theme.NumbersTextStyleDisplayMedium
+import kotlin.math.roundToInt
+
+@Composable
+fun FormattingRoute(
+    viewModel: FormattingViewModel = hiltViewModel(),
+    navigateUpAction: () -> Unit,
+) {
+    val uiState = viewModel.uiState.collectAsStateWithLifecycle()
+
+    FormattingScreen(
+        navigateUpAction = navigateUpAction,
+        uiState = uiState.value,
+        onPrecisionChange = viewModel::updatePrecision,
+        onSeparatorChange = viewModel::updateSeparator,
+        onOutputFormatChange = viewModel::updateOutputFormat,
+        togglePreview = viewModel::togglePreview
+    )
+}
+
+@Composable
+fun FormattingScreen(
+    navigateUpAction: () -> Unit,
+    uiState: FormattingUIState,
+    onPrecisionChange: (Int) -> Unit,
+    onSeparatorChange: (Int) -> Unit,
+    onOutputFormatChange: (Int) -> Unit,
+    togglePreview: () -> Unit,
+    precisions: ClosedFloatingPointRange<Float> = 0f..16f, // 16th is a MAX_PRECISION (1000)
+) {
+    UnittoScreenWithLargeTopBar(
+        title = stringResource(R.string.formatting_settings_group),
+        navigationIcon = { NavigateUpButton(navigateUpAction) },
+    ) { paddingValues ->
+        LazyColumn(
+            modifier = Modifier
+                .padding(paddingValues)
+        ) {
+            item("preview") {
+                Column(
+                    Modifier
+                        .padding(16.dp)
+                        .squashable(
+                            onClick = togglePreview,
+                            cornerRadiusRange = 8.dp..32.dp,
+                            interactionSource = remember { MutableInteractionSource() }
+                        )
+                        .background(MaterialTheme.colorScheme.secondaryContainer)
+                        .fillMaxWidth()
+                        .padding(16.dp)
+                ) {
+                    Text(
+                        text = "Preview (click to switch)",
+                        style = MaterialTheme.typography.labelMedium,
+                        color = MaterialTheme.colorScheme.onSecondaryContainer
+                    )
+                    Text(
+                        text = uiState.preview,
+                        style = NumbersTextStyleDisplayMedium,
+                        maxLines = 1,
+                        modifier = Modifier
+                            .fillMaxWidth()
+                            .horizontalScroll(rememberScrollState()),
+                        textAlign = TextAlign.End,
+                        color = MaterialTheme.colorScheme.onSecondaryContainer
+                    )
+                }
+            }
+
+            item("precision_label") {
+                ListItem(
+                    leadingContent = {
+                        Icon(Icons.Default.Architecture, stringResource(R.string.precision_setting))
+                    },
+                    headlineContent = {
+                        Row(
+                            horizontalArrangement = Arrangement.SpaceBetween,
+                            modifier = Modifier.fillMaxWidth()
+                        ) {
+                            Text(stringResource(R.string.precision_setting))
+                            Text(if (uiState.precision >= precisions.endInclusive) stringResource(R.string.max_precision) else uiState.precision.toString())
+                        }
+                    },
+                    supportingContent = {
+                        Text(stringResource(R.string.precision_setting_support))
+                    }
+                )
+            }
+
+            item("precision_slider") {
+                UnittoSlider(
+                    modifier = Modifier.padding(start = 56.dp, end = 16.dp),
+                    value = uiState.precision.toFloat(),
+                    valueRange = precisions,
+                    onValueChange = { onPrecisionChange(it.roundToInt()) },
+                )
+            }
+
+            item("separator_label") {
+                ListItem(
+                    leadingContent = {
+                        Icon(Icons.Default._123, stringResource(R.string.precision_setting))
+                    },
+                    headlineContent = { Text(stringResource(R.string.separator_setting)) },
+                    supportingContent = { Text(stringResource(R.string.separator_setting_support)) },
+                )
+            }
+
+            item("separator") {
+                Row(
+                    Modifier
+                        .horizontalScroll(rememberScrollState())
+                        .wrapContentWidth()
+                        .padding(start = 56.dp)
+                ) {
+                    SegmentedButtonsRow {
+                        SEPARATORS.forEach { (separator, stringRes) ->
+                            SegmentedButton(
+                                label = stringResource(stringRes),
+                                onClick = { onSeparatorChange(separator) },
+                                selected = separator == uiState.separator
+                            )
+                        }
+                    }
+                }
+            }
+
+            item("output_format_label") {
+                ListItem(
+                    leadingContent = {
+                        Icon(Icons.Default.EMobiledata, stringResource(R.string.precision_setting))
+                    },
+                    headlineContent = { Text(stringResource(R.string.output_format_setting)) },
+                    supportingContent = { Text(stringResource(R.string.output_format_setting_support)) }
+                )
+            }
+
+            item("output_format") {
+                Row(
+                    Modifier
+                        .horizontalScroll(rememberScrollState())
+                        .wrapContentWidth()
+                        .padding(start = 56.dp)
+                ) {
+                    SegmentedButtonsRow {
+                        OUTPUT_FORMAT.forEach { (outputFormat, stringRes) ->
+                            SegmentedButton(
+                                label = stringResource(stringRes),
+                                onClick = { onOutputFormatChange(outputFormat) },
+                                selected = outputFormat == uiState.outputFormat
+                            )
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+
+@Preview
+@Composable
+private fun PreviewFormattingScreen() {
+    var currentPrecision by remember { mutableStateOf(6) }
+    var currentSeparator by remember { mutableStateOf(Separator.COMMA) }
+    var currentOutputFormat by remember { mutableStateOf(OutputFormat.PLAIN) }
+
+    FormattingScreen(
+        uiState = FormattingUIState(
+            preview = "",
+            precision = 3,
+            separator = Separator.SPACES,
+            outputFormat = OutputFormat.PLAIN
+        ),
+        onPrecisionChange = { currentPrecision = it },
+        onSeparatorChange = { currentSeparator = it },
+        onOutputFormatChange = { currentOutputFormat = it },
+        navigateUpAction = {},
+        togglePreview = {}
+    )
+}

feature/settings/src/main/java/com/sadellie/unitto/feature/settings/formatting/FormattingUIState.kt

@@ -0,0 +1,26 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.feature.settings.formatting
+
+data class FormattingUIState(
+    val preview: String = "",
+    val precision: Int = 0,
+    val separator: Int? = null,
+    val outputFormat: Int? = null
+)

feature/settings/src/main/java/com/sadellie/unitto/feature/settings/formatting/FormattingViewModel.kt

@@ -0,0 +1,113 @@
+/*
+ * Unitto is a unit converter for Android
+ * Copyright (c) 2023 Elshan Agaev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sadellie.unitto.feature.settings.formatting
+
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import com.sadellie.unitto.core.base.MAX_PRECISION
+import com.sadellie.unitto.core.ui.common.textfield.AllFormatterSymbols
+import com.sadellie.unitto.core.ui.common.textfield.formatExpression
+import com.sadellie.unitto.data.common.setMinimumRequiredScale
+import com.sadellie.unitto.data.common.toStringWith
+import com.sadellie.unitto.data.common.trimZeros
+import com.sadellie.unitto.data.userprefs.UserPreferencesRepository
+import dagger.hilt.android.lifecycle.HiltViewModel
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.combine
+import kotlinx.coroutines.flow.stateIn
+import kotlinx.coroutines.flow.update
+import kotlinx.coroutines.launch
+import java.math.BigDecimal
+import javax.inject.Inject
+import kotlin.math.ceil
+
+@HiltViewModel
+class FormattingViewModel @Inject constructor(
+    private val userPreferencesRepository: UserPreferencesRepository
+) : ViewModel() {
+    private val _mainPreferences = userPreferencesRepository.mainPreferencesFlow
+    private val _fractional = MutableStateFlow(false)
+
+    val uiState = combine(_mainPreferences, _fractional) { mainPrefs, fractional ->
+
+        return@combine FormattingUIState(
+            preview = updatePreview(
+                fractional = fractional,
+                precision = mainPrefs.digitsPrecision,
+                outputFormat = mainPrefs.outputFormat,
+                separator = mainPrefs.separator
+            ),
+            precision = mainPrefs.digitsPrecision,
+            separator = mainPrefs.separator,
+            outputFormat = mainPrefs.outputFormat
+        )
+    }
+        .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5000L), FormattingUIState())
+
+    fun togglePreview() = _fractional.update { !it }
+
+    private fun updatePreview(
+        fractional: Boolean,
+        precision: Int,
+        outputFormat: Int,
+        separator: Int,
+    ): String {
+        val bigD = when {
+            fractional -> "0.${"0000001".padStart(precision, '0')}"
+            precision > 0 -> "123456.${"7890123456".repeat(ceil(precision.toDouble() / 10.0).toInt())}"
+            else -> "123456"
+        }
+
+        return BigDecimal(bigD)
+            .setMinimumRequiredScale(precision)
+            .trimZeros()
+            .toStringWith(outputFormat)
+            .formatExpression(AllFormatterSymbols.getById(separator))
+    }
+
+    /**
+     * @see UserPreferencesRepository.updateDigitsPrecision
+     */
+    fun updatePrecision(precision: Int) {
+        viewModelScope.launch {
+            // In UI the slider for precision goes from 0 to 16, where 16 is treated as 1000 (MAX)
+            val newPrecision = if (precision > 15) MAX_PRECISION else precision
+            userPreferencesRepository.updateDigitsPrecision(newPrecision)
+        }
+    }
+
+    /**
+     * @see UserPreferencesRepository.updateSeparator
+     */
+    fun updateSeparator(separator: Int) {
+        viewModelScope.launch {
+            userPreferencesRepository.updateSeparator(separator)
+        }
+    }
+
+    /**
+     * @see UserPreferencesRepository.updateOutputFormat
+     */
+    fun updateOutputFormat(outputFormat: Int) {
+        viewModelScope.launch {
+            userPreferencesRepository.updateOutputFormat(outputFormat)
+        }
+    }
+}

feature/settings/src/main/java/com/sadellie/unitto/feature/settings/navigation/SettingsNavigation.kt

@@ -27,8 +27,9 @@ import androidx.navigation.compose.navigation
 import com.sadellie.unitto.core.base.TopLevelDestinations
 import com.sadellie.unitto.feature.settings.AboutScreen
 import com.sadellie.unitto.feature.settings.SettingsScreen
-import com.sadellie.unitto.feature.settings.themes.ThemesRoute
 import com.sadellie.unitto.feature.settings.ThirdPartyLicensesScreen
+import com.sadellie.unitto.feature.settings.formatting.FormattingRoute
+import com.sadellie.unitto.feature.settings.themes.ThemesRoute
 import com.sadellie.unitto.feature.settings.unitgroups.UnitGroupsScreen
 import io.github.sadellie.themmo.ThemmoController
 
@@ -38,6 +39,7 @@ internal const val themesRoute = "themes_route"
 internal const val unitsGroupRoute = "units_group_route"
 internal const val thirdPartyRoute = "third_party_route"
 internal const val aboutRoute = "about_route"
+internal const val formattingRoute = "formatting_route"
 
 fun NavController.navigateToSettings(builder: NavOptionsBuilder.() -> Unit) {
     navigate(settingsRoute, builder)
@@ -85,5 +87,11 @@ fun NavGraphBuilder.settingGraph(
                 navigateUpAction = navController::navigateUp,
             )
         }
+
+        composable(formattingRoute) {
+            FormattingRoute(
+                navigateUpAction = navController::navigateUp
+            )
+        }
     }
 }