remove builder from the zoom slider example

@@ -91,59 +91,55 @@ class _BarcodeScannerWithZoomState extends State<BarcodeScannerWithZoom>
     return Scaffold(
     return Scaffold(
       appBar: AppBar(title: const Text('With zoom slider')),
       appBar: AppBar(title: const Text('With zoom slider')),
       backgroundColor: Colors.black,
       backgroundColor: Colors.black,
-      body: Builder(
-        builder: (context) {
-          return Stack(
-            children: [
-              MobileScanner(
-                controller: controller,
-                fit: BoxFit.contain,
-                errorBuilder: (context, error, child) {
-                  return ScannerErrorWidget(error: error);
-                },
-              ),
-              Align(
-                alignment: Alignment.bottomCenter,
-                child: Container(
-                  alignment: Alignment.bottomCenter,
-                  height: 100,
-                  color: Colors.black.withOpacity(0.4),
-                  child: Column(
+      body: Stack(
+        children: [
+          MobileScanner(
+            controller: controller,
+            fit: BoxFit.contain,
+            errorBuilder: (context, error, child) {
+              return ScannerErrorWidget(error: error);
+            },
+          ),
+          Align(
+            alignment: Alignment.bottomCenter,
+            child: Container(
+              alignment: Alignment.bottomCenter,
+              height: 100,
+              color: Colors.black.withOpacity(0.4),
+              child: Column(
+                children: [
+                  _buildZoomScaleSlider(),
+                  Row(
+                    mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                     children: [
                     children: [
-                      _buildZoomScaleSlider(),
-                      Row(
-                        mainAxisAlignment: MainAxisAlignment.spaceEvenly,
-                        children: [
-                          ToggleFlashlightButton(controller: controller),
-                          StartStopMobileScannerButton(controller: controller),
-                          Center(
-                            child: SizedBox(
-                              width: MediaQuery.of(context).size.width - 200,
-                              height: 50,
-                              child: FittedBox(
-                                child: Text(
-                                  barcode?.barcodes.first.rawValue ??
-                                      'Scan something!',
-                                  overflow: TextOverflow.fade,
-                                  style: Theme.of(context)
-                                      .textTheme
-                                      .headlineMedium!
-                                      .copyWith(color: Colors.white),
-                                ),
-                              ),
+                      ToggleFlashlightButton(controller: controller),
+                      StartStopMobileScannerButton(controller: controller),
+                      Center(
+                        child: SizedBox(
+                          width: MediaQuery.of(context).size.width - 200,
+                          height: 50,
+                          child: FittedBox(
+                            child: Text(
+                              barcode?.barcodes.first.rawValue ??
+                                  'Scan something!',
+                              overflow: TextOverflow.fade,
+                              style: Theme.of(context)
+                                  .textTheme
+                                  .headlineMedium!
+                                  .copyWith(color: Colors.white),
                             ),
                             ),
                           ),
                           ),
-                          SwitchCameraButton(controller: controller),
-                          AnalyzeImageFromGalleryButton(controller: controller),
-                        ],
+                        ),
                       ),
                       ),
+                      SwitchCameraButton(controller: controller),
+                      AnalyzeImageFromGalleryButton(controller: controller),
                     ],
                     ],
                   ),
                   ),
-                ),
+                ],
               ),
               ),
-            ],
-          );
-        },
+            ),
+          ),
+        ],
       ),
       ),
     );
     );
   }
   }