方法“数据”没有为类型“对象”定义。 尝试将名称更正为现有方法的名称，或定义名为“数据”的方法

Question

I have issues to display data from Firebase. Here is the code I used in my FutureBuilder. Looks like there is an error regarding data(), but I don't know which one, does anyone have any idea?

This is what I get: "The method 'data' isn't defined for the type 'Object'. Try correcting the name to the name of an existing method, or defining a method named 'data'."

if(snapshot.connectionState == ConnectionState.done) {
  Map<String, dynamic> documentData = snapshot.data!.data() as Map<String, dynamic>;
     return ListView(
       children: [

         CustomSubtitle(
           text: "${documentData['01 - Brand']}"
         ),

         CustomTitle(
           text: "${documentData['02 - Name']}",
         ),

         CustomText(
          text: "${documentData['04 - Description']}",
         )

       ],
     );
   }

Answer 1

You are using code for a QuerySnapshot . For such one your code would work but considering how you use the resulting data you received a DocumentSnapshot . For that to work just change your code to this:

if(snapshot.connectionState == ConnectionState.done) {
  Map<String, dynamic> documentData = snapshot.data as Map<String, dynamic>;
     return ListView(
       children: [

         CustomSubtitle(
           text: "${documentData['01 - Brand']}"
         ),

         CustomTitle(
           text: "${documentData['02 - Name']}",
         ),

         CustomText(
          text: "${documentData['04 - Description']}",
         )

       ],
     );
   }

Answer 2

If someone is in my case, I've found the solution:

builder: (context, AsyncSnapshot<DocumentSnapshot> snapshot) {

    if(snapshot.connectionState == ConnectionState.done) {
    DocumentSnapshot<Object?> documentData = snapshot.data!;
     return ListView(
       children: [

           CustomSubtitle(
             text: "${documentData['01 - Brand']}"
           ),

           CustomTitle(
             text: "${documentData['02 - Name']}",
           ),

           CustomText(
             text: "${documentData['04 - Description']}",
           )

         ],
       );
     }
}

Answer 3

  future: collection.doc(documentId).get(),
  builder: ((context, snapshot) {
    if (snapshot.connectionState == ConnectionState.done) {
      Map<String, dynamic> data =
          snapshot.data!.data() as Map<String, dynamic>;
      String currency = '${data['currency']}';
      
      return  Material(
          )