refactor: extract ThreeButtonNavBarLayer widget

Author: alexisdelage

lib/src/adaptive/widgets/adaptive_wrapper.dart

@@ -1,6 +1,7 @@
 import 'package:adaptive_test/src/adaptive/widgets/layers/hardware_layer.dart';
 import 'package:adaptive_test/src/adaptive/widgets/layers/keyboard_layer.dart';
 import 'package:adaptive_test/src/adaptive/widgets/layers/system_layer.dart';
+import 'package:adaptive_test/src/adaptive/widgets/layers/three_button_nav_bar_layer.dart';
 import 'package:adaptive_test/src/adaptive/window_size.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_test/flutter_test.dart';
@@ -10,6 +11,7 @@ import 'package:flutter_test/flutter_test.dart';
 /// See also:
 /// * [HardwareLayer]
 /// * [SystemLayer]
+/// * [ThreeButtonNavBarLayer]
 /// * [KeyboardLayer]
 class AdaptiveWrapper extends StatelessWidget {
   const AdaptiveWrapper({
@@ -28,9 +30,11 @@ class AdaptiveWrapper extends StatelessWidget {
       windowConfig: windowConfig,
       child: HardwareLayer(
         child: SystemLayer(
-          child: KeyboardLayer(
-            tester: tester,
-            child: child,
+          child: ThreeButtonNavBarLayer(
+            child: KeyboardLayer(
+              tester: tester,
+              child: child,
+            ),
           ),
         ),
       ),

lib/src/adaptive/widgets/layers/system_layer.dart

@@ -12,88 +12,32 @@ class SystemLayer extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final windowConfig = WindowConfig.of(context);
-
     final homeIndicator = windowConfig.homeIndicator;
-    final threeButtonNavBar = windowConfig.threeButtonNavBar;
-
-    // Case 1: Three-button nav bar
-    if (threeButtonNavBar != null) {
-      return _buildThreeButtonNavBar(context, windowConfig, threeButtonNavBar);
-    }
-
-    // Case 2: Gesture navigation (home indicator pill)
-    if (homeIndicator != null) {
-      return _buildHomeIndicator(context, windowConfig, homeIndicator);
-    }
-
-    // Case 3: No system layer
-    return child;
-  }
 
-  Widget _buildThreeButtonNavBar(
-    BuildContext context,
-    WindowConfigData windowConfig,
-    ThreeButtonNavBarData threeButtonNavBar,
-  ) =>
-      Directionality(
-        textDirection: TextDirection.ltr,
-        child: Stack(
-          children: [
-            child,
-            Positioned(
-              bottom: threeButtonNavBar.bottomPadding,
-              width: windowConfig.size.width,
+    if (homeIndicator == null) return child;
+
+    return Directionality(
+      textDirection: TextDirection.ltr,
+      child: Stack(
+        children: [
+          child,
+          Positioned(
+            bottom: homeIndicator.bottom,
+            width: windowConfig.size.width,
+            child: Center(
               child: Container(
-                height: threeButtonNavBar.height,
-                color: threeButtonNavBar.backgroundColor,
-                child: Row(
-                  mainAxisAlignment: MainAxisAlignment.spaceEvenly,
-                  children: const [
-                    Icons.arrow_back_ios_rounded,
-                    Icons.circle,
-                    Icons.square_rounded
-                  ]
-                      .map(
-                        (iconData) => Icon(
-                          iconData,
-                          color: threeButtonNavBar.iconColor,
-                          size: threeButtonNavBar.iconSize,
-                        ),
-                      )
-                      .toList(),
+                height: homeIndicator.size.height,
+                width: homeIndicator.size.width,
+                decoration: BoxDecoration(
+                  borderRadius:
+                      BorderRadius.circular(homeIndicator.size.height),
+                  color: Colors.black,
                 ),
               ),
             ),
-          ],
-        ),
-      );
-
-  Widget _buildHomeIndicator(
-    BuildContext context,
-    WindowConfigData windowConfig,
-    HomeIndicatorData homeIndicator,
-  ) =>
-      Directionality(
-        textDirection: TextDirection.ltr,
-        child: Stack(
-          children: [
-            child,
-            Positioned(
-              bottom: homeIndicator.bottom,
-              width: windowConfig.size.width,
-              child: Center(
-                child: Container(
-                  height: homeIndicator.size.height,
-                  width: homeIndicator.size.width,
-                  decoration: BoxDecoration(
-                    borderRadius:
-                        BorderRadius.circular(homeIndicator.size.height),
-                    color: Colors.black,
-                  ),
-                ),
-              ),
-            ),
-          ],
-        ),
-      );
+          ),
+        ],
+      ),
+    );
+  }
 }

lib/src/adaptive/widgets/layers/three_button_nav_bar_layer.dart

@@ -0,0 +1,52 @@
+import 'package:adaptive_test/src/adaptive/window_size.dart';
+import 'package:flutter/material.dart';
+
+class ThreeButtonNavBarLayer extends StatelessWidget {
+  const ThreeButtonNavBarLayer({
+    required this.child,
+    super.key,
+  });
+
+  final Widget child;
+
+  @override
+  Widget build(BuildContext context) {
+    final windowConfig = WindowConfig.of(context);
+    final threeButtonNavBar = windowConfig.threeButtonNavBar;
+
+    if (threeButtonNavBar == null) return child;
+
+    return Directionality(
+      textDirection: TextDirection.ltr,
+      child: Stack(
+        children: [
+          child,
+          Positioned(
+            bottom: threeButtonNavBar.bottomPadding,
+            width: windowConfig.size.width,
+            child: Container(
+              height: threeButtonNavBar.height,
+              color: threeButtonNavBar.backgroundColor,
+              child: Row(
+                mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+                children: const [
+                  Icons.arrow_back_ios_rounded,
+                  Icons.circle,
+                  Icons.square_rounded
+                ]
+                    .map(
+                      (iconData) => Icon(
+                        iconData,
+                        color: threeButtonNavBar.iconColor,
+                        size: threeButtonNavBar.iconSize,
+                      ),
+                    )
+                    .toList(),
+              ),
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}