TDMultiCascader: 修复initialIndexes 参数不生效 (Tencent#752)

* feat(级联选择器): 增加通过索引列表初始化选中位置的功能

* feat(级联选择器): 添加使用initialIndexes设置默认值的功能

* refactor(cascader): 移除冗余注释

* refactor(cascader): 使用TDCell实现示例代码

---------

Co-authored-by: Luozf <[email protected]>

Author: epoll-j

tdesign-component/example/lib/page/td_cascader_page.dart

@@ -312,6 +312,7 @@ class _TDCascaderPageState extends State<TDCascaderPage> {
           ExampleItem(desc: '测试使用次标题', builder: _buildVerticalSubTitleCascader),
           ExampleItem(desc: '垂直级联选择器-部门', builder: _buildTestVerticalCompanyCascader),
           ExampleItem(desc: '选择任意项', builder: _buildSelectAnyItemCascader),
+          ExampleItem(desc: '使用initialIndexes设置默认值', builder: _buildWithInitialIndexes),
         ],
       ),
     );
@@ -579,4 +580,36 @@ class _TDCascaderPageState extends State<TDCascaderPage> {
           );
         });
   }
+
+  @Demo(group: 'cascader')
+  Widget _buildWithInitialIndexes(BuildContext context) {
+    return TDCell(
+      title: '选择地区',
+      note: _selected_1.isEmpty ? '请选择' : _selected_1,
+      arrow: true,
+      onClick: (click) {
+        TDCascader.showMultiCascader(
+          context,
+          title: '选择地址',
+          data: _data,
+          initialIndexes: [0, 0, 1],
+          theme: 'step',
+          onChange: (List<MultiCascaderListModel> selectData) {
+            setState(() {
+              var result = [];
+              var len = selectData.length;
+              _initData = selectData[len - 1].value!;
+              selectData.forEach((element) {
+                result.add(element.label);
+              });
+              _selected_1 = result.join('/');
+            });
+          },
+          onClose: () {
+            Navigator.of(context).pop();
+          },
+        );
+      },
+    );
+  }
 }

tdesign-component/lib/src/components/cascader/td_multi_cascader.dart

@@ -115,21 +115,25 @@ class _TDMultiCascaderState extends State<TDMultiCascader>
     if (widget.isLetterSort) {
       _listDataSegmenter();
     }
-    _initLocation(widget.initialData ?? '');
+    // 优先使用 initialIndexes，如果没有则使用 initialData
+    String? initValue;
+    if (widget.initialIndexes != null && widget.initialIndexes!.isNotEmpty) {
+      initValue = _initLocationByIndexes(widget.initialIndexes!);
+    } else {
+      _initLocation(widget.initialData??'');
+    }
+    
     _currentTabIndex = _tabListData.length - 1;
-    _level = _currentTabIndex > 0 ? _currentTabIndex : 0;
-    if (_currentTabIndex >= 0) {
+    _level = _currentTabIndex>0?_currentTabIndex:0;
+    if(_currentTabIndex>=0){
       _tabListData = _tabListData.reversed.toList();
-      _selectTabValue = widget.initialData;
-      _selectListData = _listData
-          .where((element) =>
-              element.parentValue == _tabListData[_currentTabIndex].parentValue)
-          .toList();
-    } else {
+      _selectTabValue = initValue ?? widget.initialData;
       _selectListData =
-          _listData.where((element) => element.level == 0).toList();
+          _listData.where((element) => element.parentValue == _tabListData[_currentTabIndex].parentValue).toList();
+    }else{
+      _selectListData = _listData.where((element) => element.level == 0).toList();
       _tabListData.add(MultiCascaderListModel(
-        labelFun: () => context.resource.cascadeLabel,
+        labelFun: ()=>context.resource.cascadeLabel,
       ));
     }
   }
@@ -190,6 +194,46 @@ class _TDMultiCascaderState extends State<TDMultiCascader>
     }
   }
 
+  /// 根据索引列表初始化选中位置
+  String? _initLocationByIndexes(List<int> indexes) {
+    if (indexes.isEmpty) return null;
+    
+    String? lastValue = _getValueByIndexes(indexes);
+    
+    if (lastValue != null) {
+      _initLocation(lastValue);
+    }
+
+    return lastValue;
+  }
+  
+  /// 根据索引列表获取对应的值
+  String? _getValueByIndexes(List<int> indexes) {
+    if (indexes.isEmpty) return null;
+    
+    List<dynamic> currentLevel = widget.data;
+    String? value;
+    
+    for (int i = 0; i < indexes.length; i++) {
+      int index = indexes[i];
+      
+      if (index >= 0 && index < currentLevel.length) {
+        Map item = currentLevel[index];
+        value = item['value'];
+        
+        if (i < indexes.length - 1 && item.containsKey('children') && item['children'] is List && item['children'].isNotEmpty) {
+          currentLevel = item['children'];
+        } else {
+          break;
+        }
+      } else {
+        return null;
+      }
+    }
+    
+    return value;
+  }
+
   void _listDataSegmenter() {
     _listData.sort((a, b) {
       if (a.segmentValue == null || b.segmentValue == null) {