feat : overlay dropdown list

packages/core/lib/presentation/widget/overlay_dropdown_widget/view.dart

@@ -0,0 +1,143 @@
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+import 'package:get/get.dart';
+import 'package:rasadyar_core/presentation/common/app_color.dart';
+import 'package:rasadyar_core/presentation/common/app_fonts.dart';
+
+
+
+class OverlayDropdownWidget<T> extends StatefulWidget {
+  final List<T> items;
+  final T? selectedItem;
+  final T? initialValue;
+  final Widget Function(T item) itemBuilder;
+  final Widget Function(T? selected) labelBuilder;
+  final void Function(T selected)? onChanged;
+  final EdgeInsets? contentPadding;
+
+   const OverlayDropdownWidget({
+    super.key,
+    required this.items,
+    required this.itemBuilder,
+    required this.labelBuilder,
+    this.initialValue,
+    this.onChanged,
+    this.selectedItem,
+     this.contentPadding
+  });
+
+  @override
+  State<OverlayDropdownWidget<T>> createState() => _OverlayDropdownState<T>();
+}
+
+class _OverlayDropdownState<T> extends State<OverlayDropdownWidget<T>> {
+  final GlobalKey _key = GlobalKey();
+  OverlayEntry? _overlayEntry;
+  final RxBool _isOpen = false.obs;
+  T? selectedItem ;
+
+  @override
+  void initState() {
+    super.initState();
+    selectedItem = widget.selectedItem ?? widget.initialValue;
+  }
+
+  void _showOverlay() {
+    final renderBox = _key.currentContext!.findRenderObject() as RenderBox;
+    final size = renderBox.size;
+    final offset = renderBox.localToGlobal(Offset.zero);
+
+    _overlayEntry = OverlayEntry(
+      builder:
+          (_) => GestureDetector(
+            onTap: _removeOverlay,
+            behavior: HitTestBehavior.translucent,
+            child: Stack(
+              children: [
+                Positioned(
+                  left: offset.dx,
+                  top: offset.dy + size.height + 4,
+                  width: size.width,
+                  child: Material(
+                    elevation: 4,
+                    borderRadius: BorderRadius.circular(8),
+                    child: Container(
+                      decoration: BoxDecoration(
+                        color: Colors.white,
+                        border: Border.all(color: AppColor.darkGreyLight),
+                        borderRadius: BorderRadius.circular(8),
+                      ),
+                      child: ListView(
+                        padding: EdgeInsets.zero,
+                        shrinkWrap: true,
+                        children:
+                            widget.items.map((item) {
+                              return InkWell(
+                                onTap: () {
+                                  widget.onChanged?.call(item);
+                                  setState(() {
+                                    selectedItem = item;
+                                  });
+                                  _removeOverlay();
+                                },
+                                child: Padding(
+                                  padding:widget.contentPadding?? const EdgeInsets.symmetric(horizontal: 8, vertical: 4),
+                                  child: widget.itemBuilder(item),
+                                ),
+                              );
+                            }).toList(),
+                      ),
+                    ),
+                  ),
+                ),
+              ],
+            ),
+          ),
+    );
+
+    Overlay.of(context).insert(_overlayEntry!);
+    _isOpen.value = true;
+  }
+
+  void _removeOverlay() {
+    _overlayEntry?.remove();
+    _overlayEntry = null;
+    _isOpen.value = false;
+  }
+
+  @override
+  void dispose() {
+    _removeOverlay();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return GestureDetector(
+      key: _key,
+      onTap: () {
+        _isOpen.value ? _removeOverlay() : _showOverlay();
+      },
+      child: Container(
+        height: 40,
+        width: Get.width,
+        padding: const EdgeInsets.symmetric(horizontal: 12),
+        decoration: BoxDecoration(
+          border: Border.all(color: AppColor.darkGreyLight),
+          borderRadius: BorderRadius.circular(8),
+        ),
+        child: Row(
+          mainAxisAlignment: MainAxisAlignment.spaceBetween,
+          children: [
+            widget.labelBuilder(selectedItem),
+            Icon(
+              _isOpen.value
+                  ? CupertinoIcons.chevron_up
+                  : CupertinoIcons.chevron_down,
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}