如何在 Flutter 的 DropdownButton 中获取选中项的索引号？

Question

I populate the dropdown menu with the GET Request's distList.sectionName values. What I am trying to do is catch the index of the selected museum and then send this index's values to the another API call. For example; lets say user is select the "İnte.net Müzesi" in the dropdown menu. After that I need to locate the position of the "İnte.net Müzesi" in the distList. And then catch this two fields: "distId": "MRK" and "sectionId": "INT01" values so I can send these values to another API call. How can I achieve this?

My DropdownButton widget:

Container(
    child: DropdownButton<String>(
      hint: Text("Lütfen listeden seçim yapın."),
      items: snapshot.data.distList
          .map<DropdownMenuItem<String>>((item) {
        return DropdownMenuItem<String>(
            value: item.sectionName,
            child: Text(item.sectionName));
      }).toList(),
      value: _currentSelectedValue,
      isExpanded: false,
      onChanged: (String? value) {
        print("Drop Down Selected Museum is $value");
        setState(() {
          _currentSelectedValue = value;
        });
      },
    ),
  ),

Here is my GET Request response:

    "distList": [
        {
            "distId": "MRK",
            "sectionId": "INT01",
            "sectionName": "İnternet Müzesi",
            "sectionNameEng": null
        },
        {
            "distId": "IAR",
            "sectionId": "IAR01",
            "sectionName": "İstanbul Arkeoloji Müzesi",
            "sectionNameEng": "İSTANBUL ARCHAEOLOGICAL MUSEUMS"
        },
        {
            "distId": "TPK",
            "sectionId": "TPK01",
            "sectionName": "İstanbul Topkapı Sarayı Müzesi",
            "sectionNameEng": "TOPKAPI PALACE MUSEUM"
        },
        {
            "distId": "MRK",
            "sectionId": "CUM01",
            "sectionName": "Ankara Cumhuriyet Müzesi",
            "sectionNameEng": "MUSEUM OF REPUBLIC OF ANKARA"
        }
    ],
    "acknowledge": true,
    "message": null,
    "requestId": null
}

Answer 1

ok, I found the solution.

in the setState I catch the selectedValue's field like this:

                                  _currentSelectedValue = value;
                                  var var2 = snapshot.data.distList!.firstWhere(
                                      (e) =>
                                          e.sectionName ==
                                          "$_currentSelectedValue");
                                  print(var2.distId);
                                  print(var2.sectionId);
                                });