类型 'String' 不是类型 'ImageProvider<dynamic>' 的子类型

Question

我有类别列表，点击每个类别会在新屏幕中显示该类别的用户。新屏幕有一个 image 小部件和 text 小部件。如果用户有 profile picture，并且没有与该用户关联的个人资料图片，则会显示不会引发此错误的默认图片，我会收到此错误。

Widget _getProfilePic(Pro pro) {

    // If the pro has provided a profile picture
    if(pro.profilePhoto.length > 0) {

      // If the pro is available for a video call
      if(statusMap[pro.onlineStatus] == "Online, available") {
        return CircleAvatar(
            radius: 30.0,
            backgroundImage: pro.profilePhoto.startsWith("./profilepics") ? NetworkImage("" + pro.profilePhoto.substring(2)) : pro.profilePhoto);
      }
      // If pro is not available
      else {
        return CircleAvatar(
            radius: 30.0,
            backgroundImage: pro.profilePhoto.startsWith("./profilepics") ? NetworkImage("" + pro.profilePhoto.substring(2)) : pro.profilePhoto);
      }

    }
    // Else, provide a default icon
    else {
      // If the pro is available for a video call
      if(statusMap[pro.onlineStatus] == "Online, available") {
        var profileImg = Image.asset('icons/default_profile_icon.png', height: 60.0);

        return Image.asset('icons/default_profile_icon.png', height: 60.0);

      }
      // If the pro is not available
      else {
        return Image.asset('icons/default_profile_icon.png', height: 60.0);
      }
    }

这是Proclass型号：

class Pro extends User {
  String company;
  String experience;
  double rating;
  int reviewCount;
  int onlineStatus;
  String proId;

  Pro();

  // Returns a Pro created from JSON
  factory Pro.fromJson(Map<String, dynamic> json) {
    Pro pro = Pro();

    pro.proId = json['ProID'] as String;
    pro.fullname = json['FullName'] as String;
    pro.company = json['Company'] as String;
    pro.experience = json['about'] as String;
    pro.rating = json['ReviewAvg'] != null? double.tryParse(json['ReviewAvg']) : 0.0;
    pro.reviewCount = json['ReviewCount'];
    pro.onlineStatus = json['OnlineStatus'];
    pro.profilePhoto = json['profile_pic'] as String;

    return pro;
  }

}

// Converts a http response body into a List<Pro>
  List<Pro> parsePros(String responseBody) {
    final parsed = json.decode(responseBody).cast<Map<String, dynamic>>();
    return parsed.map<Pro>((json) => Pro.fromJson(json)).toList();
  }

Answer 1

您可能需要在测试 ./profilepics

的两个地方将 pro.profileImage 包裹在 NetworkImage 中

类型 'String' 不是类型 'ImageProvider<dynamic>' 的子类型

type 'String' is not a subtype of type 'ImageProvider<dynamic>'

flutter

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