Add NavigationBar component

libraries/designsystem/src/main/kotlin/io/element/android/libraries/designsystem/atomic/atoms/CounterAtom.kt

@@ -17,7 +17,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
-import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.text.TextStyle
 import androidx.compose.ui.text.rememberTextMeasurer
 import androidx.compose.ui.unit.dp
 import io.element.android.compound.theme.ElementTheme
@@ -41,13 +41,14 @@ private const val MAX_COUNT_STRING = "+$MAX_COUNT"
 fun CounterAtom(
     count: Int,
     modifier: Modifier = Modifier,
+    textStyle: TextStyle = CounterAtomDefaults.textStyle,
+    isCritical: Boolean = false,
 ) {
     if (count < 1) return
     val countAsText = when (count) {
         in 0..MAX_COUNT -> count.toString()
         else -> MAX_COUNT_STRING
     }
-    val textStyle = ElementTheme.typography.fontBodyMdMedium
     val textMeasurer = rememberTextMeasurer()
     // Measure the maximum count string size
     val textLayoutResult = textMeasurer.measure(
@@ -58,19 +59,30 @@ fun CounterAtom(
     val squareSize = maxOf(textSize.width, textSize.height)
     Box(
         modifier = modifier
-                .size(squareSize.toDp() + 1.dp)
+            .size(squareSize.toDp() + 1.dp)
-                .clip(CircleShape)
+            .clip(CircleShape)
-                .background(ElementTheme.colors.iconSuccessPrimary)
+            .background(
+                if (isCritical) {
+                    ElementTheme.colors.iconCriticalPrimary
+                } else {
+                    ElementTheme.colors.iconAccentPrimary
+                }
+            )
     ) {
         Text(
             modifier = Modifier.align(Alignment.Center),
             text = countAsText,
             style = textStyle,
-            color = Color.White,
+            color = ElementTheme.colors.textOnSolidPrimary,
         )
     }
 }
 
+object CounterAtomDefaults {
+    val textStyle: TextStyle
+        @Composable get() = ElementTheme.typography.fontBodyMdMedium
+}
+
 @PreviewsDayNight
 @Composable
 internal fun CounterAtomPreview() = ElementPreview {
@@ -79,5 +91,6 @@ internal fun CounterAtomPreview() = ElementPreview {
         CounterAtom(count = 4)
         CounterAtom(count = 99)
         CounterAtom(count = 100)
+        CounterAtom(count = 4, isCritical = true)
     }
 }

libraries/designsystem/src/main/kotlin/io/element/android/libraries/designsystem/theme/components/NavigationBar.kt

@@ -0,0 +1,186 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.designsystem.theme.components
+
+import androidx.compose.foundation.interaction.MutableInteractionSource
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.RowScope
+import androidx.compose.foundation.layout.WindowInsets
+import androidx.compose.foundation.layout.offset
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.NavigationBarDefaults
+import androidx.compose.material3.NavigationBarItemColors
+import androidx.compose.material3.NavigationBarItemDefaults
+import androidx.compose.material3.contentColorFor
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.dp
+import io.element.android.compound.theme.ElementTheme
+import io.element.android.compound.tokens.generated.CompoundIcons
+import io.element.android.libraries.designsystem.atomic.atoms.CounterAtom
+import io.element.android.libraries.designsystem.preview.ElementThemedPreview
+import io.element.android.libraries.designsystem.preview.PreviewGroup
+import androidx.compose.material3.NavigationBarItem as MaterialNavigationBarItem
+
+@Composable
+fun NavigationBar(
+    modifier: Modifier = Modifier,
+    containerColor: Color = ElementNavigationBarDefaults.containerColor,
+    contentColor: Color = MaterialTheme.colorScheme.contentColorFor(containerColor),
+    tonalElevation: Dp = ElementNavigationBarDefaults.tonalElevation,
+    windowInsets: WindowInsets = ElementNavigationBarDefaults.windowInsets,
+    content: @Composable RowScope.() -> Unit
+) {
+    androidx.compose.material3.NavigationBar(
+        modifier = modifier,
+        containerColor = containerColor,
+        contentColor = contentColor,
+        tonalElevation = tonalElevation,
+        windowInsets = windowInsets,
+        content = content
+    )
+}
+
+object ElementNavigationBarDefaults {
+    val containerColor: Color
+        @Composable get() = if (ElementTheme.isLightTheme) {
+            ElementTheme.colors.bgSubtlePrimary
+        } else {
+            ElementTheme.colors.textOnSolidPrimary
+        }
+
+    val tonalElevation: Dp = NavigationBarDefaults.Elevation
+
+    val windowInsets: WindowInsets
+        @Composable get() = NavigationBarDefaults.windowInsets
+}
+
+@Composable
+fun RowScope.NavigationBarItem(
+    selected: Boolean,
+    onClick: () -> Unit,
+    icon: @Composable () -> Unit,
+    modifier: Modifier = Modifier,
+    enabled: Boolean = true,
+    label: @Composable (() -> Unit)? = null,
+    alwaysShowLabel: Boolean = true,
+    colors: NavigationBarItemColors = ElementNavigationBarItemDefaultsDefaults.colors(),
+    interactionSource: MutableInteractionSource? = null
+) {
+    MaterialNavigationBarItem(
+        selected = selected,
+        onClick = onClick,
+        icon = icon,
+        modifier = modifier,
+        enabled = enabled,
+        label = label,
+        alwaysShowLabel = alwaysShowLabel,
+        colors = colors,
+        interactionSource = interactionSource,
+    )
+}
+
+object ElementNavigationBarItemDefaultsDefaults {
+    @Composable
+    fun colors() = NavigationBarItemDefaults.colors().copy(
+        selectedIconColor = ElementTheme.colors.iconPrimary,
+        selectedTextColor = ElementTheme.colors.textPrimary,
+        unselectedIconColor = ElementTheme.colors.iconTertiary,
+        unselectedTextColor = ElementTheme.colors.textDisabled,
+        selectedIndicatorColor = Color.Transparent,
+    )
+}
+
+@Composable
+fun NavigationBarIcon(
+    imageVector: ImageVector,
+    count: Int,
+    isCritical: Boolean,
+) {
+    Box {
+        Icon(
+            imageVector = imageVector,
+            contentDescription = null,
+        )
+        CounterAtom(
+            modifier = Modifier.offset(11.dp, (-11).dp),
+            textStyle = ElementTheme.typography.fontBodyXsMedium,
+            count = count,
+            isCritical = isCritical,
+        )
+    }
+}
+
+@Composable
+fun NavigationBarText(
+    text: String,
+) {
+    Text(
+        text = text,
+        style = ElementTheme.typography.fontBodySmMedium,
+    )
+}
+
+@Preview(group = PreviewGroup.AppBars)
+@Composable
+internal fun NavigationBarPreview() = ElementThemedPreview {
+    NavigationBar {
+        NavigationBarItem(
+            icon = {
+                NavigationBarIcon(
+                    imageVector = CompoundIcons.ChatSolid(),
+                    count = 5,
+                    isCritical = false,
+                )
+            },
+            label = {
+                NavigationBarText(
+                    text = "Chats"
+                )
+            },
+            selected = true,
+            onClick = {},
+        )
+        NavigationBarItem(
+            icon = {
+                NavigationBarIcon(
+                    imageVector = CompoundIcons.ChatSolid(),
+                    count = 5,
+                    isCritical = true,
+                )
+            },
+            label = {
+                NavigationBarText(
+                    text = "Teams"
+                )
+            },
+            selected = false,
+            onClick = {},
+        )
+        NavigationBarItem(
+            icon = {
+                NavigationBarIcon(
+                    imageVector = CompoundIcons.ChatSolid(),
+                    count = 0,
+                    isCritical = false,
+                )
+            },
+            label = {
+                NavigationBarText(
+                    text = "Other"
+                )
+            },
+            selected = false,
+            onClick = {},
+        )
+    }
+}

tests/konsist/src/test/kotlin/io/element/android/tests/konsist/KonsistComposableTest.kt

@@ -34,6 +34,8 @@ class KonsistComposableTest {
                 // Add some exceptions...
                 "InvisibleButton",
                 "OutlinedButton",
+                "NavigationBarIcon",
+                "NavigationBarText",
                 "SimpleAlertDialogContent",
                 "TextButton",
             )