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Firebase 从QuerySnapshot到未来的颤振转换<;列表<;地图<;动态,动态>&燃气轮机&燃气轮机;_Firebase_Dictionary_Dart_Google Cloud Firestore_Flutter - Fatal编程技术网

Firebase 从QuerySnapshot到未来的颤振转换<;列表<;地图<;动态,动态>&燃气轮机&燃气轮机;

Firebase 从QuerySnapshot到未来的颤振转换<;列表<;地图<;动态,动态>&燃气轮机&燃气轮机;,firebase,dictionary,dart,google-cloud-firestore,flutter,Firebase,Dictionary,Dart,Google Cloud Firestore,Flutter,如何将QuerySnapshot作为未来>>返回 代码段: Future <List<Map<dynamic, dynamic>>>() { List<Map<dynamic,dynamic>> list; ..... ..... QuerySnapshot collectionSnapshot = await collectionRef.getDocuments(); list = collectionSnapshot.docum

如何将QuerySnapshot作为未来>>返回

代码段:

Future <List<Map<dynamic, dynamic>>>() {
List<Map<dynamic,dynamic>> list;
.....

.....
QuerySnapshot collectionSnapshot = await collectionRef.getDocuments();

list = collectionSnapshot.documents;  <--- ERROR
return list;

}
Future(){
名单;
.....
.....
QuerySnapshot collectionSnapshot=await collectionRef.getDocuments();

list=collectionSnapshot.documents;collectionSnapshot.documents返回列表而不是列表类型,您需要将文档快照列表转换为
list
。 我的想法可能是这样的:

Future <List<Map<dynamic, dynamic>>> getCollection() async{
List<DocumentSnapshot> templist;
List<Map<dynamic, dynamic>> list = new List();
CollectionReference collectionRef = Firestore.instance.collection("path");
QuerySnapshot collectionSnapshot = await collectionRef.getDocuments();

templist = collectionSnapshot.documents; // <--- ERROR

list = templist.map((DocumentSnapshot docSnapshot){
  return docSnapshot.data;
}).toList();

return list;
}  
Future getCollection()异步{
圣殿骑士名单;
列表=新列表();
CollectionReference collectionRef=Firestore.instance.collection(“路径”);
QuerySnapshot collectionSnapshot=await collectionRef.getDocuments();
templast=collectionSnapshot.documents//