feat: show branches count

lib/models/theme.dart

@@ -1,6 +1,8 @@
 import 'dart:io';
+import 'dart:async';
 import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
+import 'package:git_touch/widgets/picker.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 
 class DialogOption<T> {
@@ -180,4 +182,50 @@ class ThemeModel with ChangeNotifier {
         );
     }
   }
+
+  static Timer _debounce;
+
+  showPicker(BuildContext context, PickerGroupItem<String> groupItem) async {
+    switch (theme) {
+      case AppThemeType.cupertino:
+        await showCupertinoModalPopup<void>(
+          context: context,
+          builder: (context) {
+            return Container(
+              height: 300,
+              child: CupertinoPicker(
+                backgroundColor: CupertinoColors.white,
+                children: groupItem.items.map((v) => Text(v.text)).toList(),
+                itemExtent: 40,
+                scrollController: FixedExtentScrollController(
+                    initialItem: groupItem.items
+                        .toList()
+                        .indexWhere((v) => v.value == groupItem.value)),
+                onSelectedItemChanged: (index) {
+                  if (_debounce?.isActive ?? false) _debounce.cancel();
+                  _debounce = Timer(const Duration(milliseconds: 500), () {
+                    return groupItem
+                        .onChange(groupItem.items.toList()[index].value);
+                  });
+                },
+              ),
+            );
+          },
+        );
+        break;
+      default:
+        final value = await showMenu(
+          context: context,
+          initialValue: groupItem.value,
+          items: groupItem.items
+              .map((item) =>
+                  PopupMenuItem(value: item.value, child: Text(item.text)))
+              .toList(),
+          position: RelativeRect.fill,
+        );
+        if (value != null) {
+          groupItem.onChange(value);
+        }
+    }
+  }
 }