Add some previews.

features/preferences/src/main/kotlin/io/element/android/features/preferences/user/UserPreferences.kt

@@ -20,9 +20,14 @@ import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.height
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.tooling.preview.PreviewParameter
 import androidx.compose.ui.unit.dp
 import io.element.android.libraries.architecture.Async
+import io.element.android.libraries.designsystem.preview.ElementPreviewDark
+import io.element.android.libraries.designsystem.preview.ElementPreviewLight
 import io.element.android.libraries.matrix.ui.components.MatrixUserHeader
+import io.element.android.libraries.matrix.ui.components.MatrixUserWithNullProvider
 import io.element.android.libraries.matrix.ui.model.MatrixUser
 
 @Composable
@@ -38,3 +43,22 @@ fun UserPreferences(
         )
     }
 }
+
+@Preview
+@Composable
+internal fun UserPreferencesLightPreview(@PreviewParameter(MatrixUserWithNullProvider::class) matrixUser: MatrixUser?) =
+    ElementPreviewLight { ContentToPreview(matrixUser) }
+
+@Preview
+@Composable
+internal fun UserPreferencesDarkPreview(@PreviewParameter(MatrixUserWithNullProvider::class) matrixUser: MatrixUser?) =
+    ElementPreviewDark { ContentToPreview(matrixUser) }
+
+@Composable
+private fun ContentToPreview(matrixUser: MatrixUser?) {
+    if (matrixUser == null) {
+        UserPreferences(Async.Uninitialized)
+    } else {
+        UserPreferences(Async.Success(matrixUser))
+    }
+}

libraries/matrixui/src/main/kotlin/io/element/android/libraries/matrix/ui/components/MatrixUserProvider.kt

@@ -25,8 +25,7 @@ open class MatrixUserProvider : PreviewParameterProvider<MatrixUser> {
     override val values: Sequence<MatrixUser>
         get() = sequenceOf(
             aMatrixUser(),
-            MatrixUser(
-                id = UserId("@id_of_alice:server.org"),
+            aMatrixUser().copy(
                 username = null,
                 avatarData = anAvatarData().copy(name = null)
             ),
@@ -38,3 +37,15 @@ fun aMatrixUser() = MatrixUser(
     username = "Alice",
     avatarData = anAvatarData()
 )
+
+open class MatrixUserWithNullProvider : PreviewParameterProvider<MatrixUser?> {
+    override val values: Sequence<MatrixUser?>
+        get() = sequenceOf(
+            aMatrixUser(),
+            aMatrixUser().copy(
+                username = null,
+                avatarData = anAvatarData().copy(name = null)
+            ),
+            null,
+        )
+}