Add scaffold preview.

app/src/main/java/org/thoughtcrime/securesms/components/settings/app/privacy/pnp/PhoneNumberPrivacySettingsFragment.kt

@@ -39,7 +39,7 @@ class PhoneNumberPrivacySettingsFragment : ComposeFragment() {
     Scaffolds.Settings(
       title = stringResource(id = R.string.preferences_app_protection__phone_number),
       onNavigationClick = onNavigationClick,
-      painter = painterResource(id = R.drawable.ic_arrow_left_24),
+      navigationIconPainter = painterResource(id = R.drawable.ic_arrow_left_24),
       navigationContentDescription = stringResource(id = R.string.Material3SearchToolbar__close)
     ) { contentPadding ->
       Box(modifier = Modifier.padding(contentPadding)) {

core-ui/src/main/java/org/signal/core/ui/Scaffolds.kt

@@ -1,6 +1,8 @@
 package org.signal.core.ui
 
+import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.padding
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.Icon
@@ -10,9 +12,14 @@ import androidx.compose.material3.Scaffold
 import androidx.compose.material3.Text
 import androidx.compose.material3.TopAppBar
 import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.painter.ColorPainter
 import androidx.compose.ui.graphics.painter.Painter
+import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
+import org.signal.core.ui.theme.SignalTheme
 
 @OptIn(ExperimentalMaterial3Api::class)
 object Scaffolds {
@@ -20,7 +27,7 @@ object Scaffolds {
   fun Settings(
     title: String,
     onNavigationClick: () -> Unit,
-    painter: Painter,
+    navigationIconPainter: Painter,
     modifier: Modifier = Modifier,
     navigationContentDescription: String? = null,
     content: @Composable (PaddingValues) -> Unit
@@ -40,7 +47,7 @@ object Scaffolds {
               Modifier.padding(end = 16.dp)
             ) {
               Icon(
-                painter = painter,
+                painter = navigationIconPainter,
                 contentDescription = navigationContentDescription
               )
             }
@@ -52,3 +59,22 @@ object Scaffolds {
     )
   }
 }
+
+@Preview
+@Composable
+fun SettingsScaffoldPreview() {
+  SignalTheme(isDarkMode = false) {
+    Scaffolds.Settings(
+      "Settings Scaffold",
+      onNavigationClick = {},
+      navigationIconPainter = ColorPainter(Color.Black)
+    ) { paddingValues ->
+      Box(
+        contentAlignment = Alignment.Center,
+        modifier = Modifier.padding(paddingValues).fillMaxSize()
+      ) {
+        Text("Content")
+      }
+    }
+  }
+}