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Flutter:如何解決值類型 Object 無法分配給 Map<string, dynamic> 在流構建器上</string,>

[英]Flutter: How to solve value type Object can't be assigned to Map<String, dynamic> on streambuilder

我試圖從 firebase 獲取數據並將數據顯示到列表中,但在嘗試將 map 文檔數據放入列表以顯示其內容時出現錯誤

在此處輸入圖像描述

這是我的代碼

StreamBuilder<QuerySnapshot>(
                stream: users.snapshots(),
                builder: (BuildContext context,
                    AsyncSnapshot<QuerySnapshot> snapshot) {
                  if (snapshot.hasError) {
                    return const Center(
                      child: Text("Something went wrong"),
                    );
                  }

                  if (snapshot.connectionState == ConnectionState.waiting) {
                    return const Center(
                      child: Text("Loading"),
                    );
                  }

                  if (snapshot.hasData) {
                    return CustomScrollView(
                      slivers: [
                        SliverList(
                          delegate: SliverChildListDelegate(
                            snapshot.data!.docs.map(
                              (DocumentSnapshot document) {
                                Map<String, dynamic> data = document.data()!;
                                return ListTile(
                                  onTap: () => callChatDetailsScreen(
                                      context, data['name'], data['uid']),
                                  title: Text(data['name']),
                                  subtitle: Text(data['status']),
                                );
                              },
                            ).toList(),
                          ),
                        )
                      ],
                    );
                  }
                  return Container();
                })

我怎樣才能解決這個問題?

改變這個:

(DocumentSnapshot document) {

進入這個:

(DocumentSnapshot<Map<String,dynamic>> document) {

data() data() T類型的值,class DocumenSnapshot以這種方式聲明: abstract class DocumentSnapshot abstract class DocumentSnapshot<T extends Object?> Object

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