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Flutter 如何允许在Flatter中从FutureBuilder导航到其他页面_Flutter_Dart_Flutter Layout_Flutter Navigation_Flutter Http - Fatal编程技术网

Flutter 如何允许在Flatter中从FutureBuilder导航到其他页面

Flutter 如何允许在Flatter中从FutureBuilder导航到其他页面,flutter,dart,flutter-layout,flutter-navigation,flutter-http,Flutter,Dart,Flutter Layout,Flutter Navigation,Flutter Http,在下面的代码中,我创建了一个登录屏幕,在该屏幕中,在执行API调用之后,所以在获得想要导航到下一个屏幕的数据之后,我从future builder进行导航,但它不起作用 所以,请帮忙 futureBuilder<Album>( future: userFuture, builder: (ctx, snapshot) { if (s

在下面的代码中,我创建了一个登录屏幕,在该屏幕中,在执行API调用之后,所以在获得想要导航到下一个屏幕的数据之后,我从future builder进行导航,但它不起作用

所以,请帮忙

    futureBuilder<Album>(
                        future: userFuture,
                        builder: (ctx, snapshot) {
                          if (snapshot.hasData) {
                            isApiCall = false;
                            print("hasDat");
                            if (snapshot.data.errorMsg == "") {
                              _showToast(snapshot.data.errorMsg);
                            } else {

// I added this part to navigate screen, but it did not works
                               Navigator.of(context).push(MaterialPageRoute(builder: (context) => Home()));
                              //_showToast(snapshot.data.errorMsg);
                              //return Home();
                              if(snapshot.connectionState == ConnectionState.waiting){
                                return CircularProgressIndicator();
                              }
                              else{

                                navigateToNextScreen=true;
                              }
                              Navigator.of(context).push(MaterialPageRoute(builder: (context) => Home()));
                              //return Text(snapshot.data.errorMsg);
                            }
                          } else if (snapshot.hasError) {

                          }

                          return CircularProgressIndicator();
                        },
                      )),
下面是statefull小部件中的未来对象

Future<Album> userFuture;

       @override
      void initState() {

        super.initState();
        userFuture=_futureAlbum();
      }

    Future<Album>_futureAlbum()async{
        if (isApiCall){
        return await createAlbum("http://api/login01", {
                                      'userPhoneNumber':
                                          "91" + controller.text.toString(),
                                      'userPassword':
                                          _passwordController.text.toString()
                                    });}
        else{
          return null;
        }

      }
未来用户未来;
@凌驾
void initState(){
super.initState();
用户未来=_未来相册();
}
Future\u futureAlbum()异步{
如果(isApiCall){
返回等待创建相册(“http://api/login01", {
“用户电话号码”:
“91”+controller.text.toString(),
“用户密码”:
_passwordController.text.toString()
});}
否则{
返回null;
}
}
下面是我的API的调用类和方法,它们被上述函数调用

class Album {
  final String errorMsg ;
  final Map success;

  Album({this.errorMsg, this.success});

  factory Album.fromJson(Map<String, dynamic> json) {
    if (json.containsKey("error")){
      print(json["error"]["errorMsg"]);
      print("sfsdfdsdfsfd");
      return Album(errorMsg:json["error"]["errorMsg"].toString());
    }

    else{return Album(success:json["success"]);}
  }
}
Future<Album> createAlbum(String url, Map reqBody) async {
      final Map success={};
      final Map errorMsg={};
      final Map res={};
      final http.Response response = await http.post(
        url,
        headers: <String, String>{
          'Content-Type': 'application/json',
        },
        body: jsonEncode(reqBody),
      );

      if (response.statusCode == 200) {
        print(response.body);
        Map<dynamic, dynamic>res = json.decode(response.body);
        return Album.fromJson(json.decode(response.body));
      } else {
        throw Exception('Failed to create album.');
      }
    }
类相册{
最后一个字符串errorMsg;
最终地图成功;
相册({this.errorMsg,this.success});
factory Album.fromJson(映射json){
if(json.containsKey(“错误”)){
打印(json[“error”][“errorMsg”]);
打印(“sfsdfdsdfsfd”);
返回相册(errorMsg:json[“error”][“errorMsg”].toString());
}
else{return Album(success:json[“success”]);}
}
}
Future createAlbum(字符串url,映射请求体)异步{
最终映射成功={};
最终映射errorMsg={};
最终映射res={};
final http.Response Response=wait http.post(
网址,
标题:{
“内容类型”:“应用程序/json”,
},
正文:JSONECODE(reqBody),
);
如果(response.statusCode==200){
打印(响应.正文);
Mapres=json.decode(response.body);
返回Album.fromJson(json.decode(response.body));
}否则{
抛出异常('未能创建相册');
}
}

一个好的选择是在这里使用记忆技术。在函数编程和递归中常用的记忆,可以用来将函数返回的值保存在内存中,这样函数就不必再次运行。除此之外,唯一的选择是不更改页面并将整个小部件嵌套在Futurebuilder本身中。

一个好的选择是在此处使用记忆技术。在函数编程和递归中常用的记忆,可以用来将函数返回的值保存在内存中,这样函数就不必再次运行。除此之外,唯一的选择是不更改页面并将整个小部件嵌套在Futurebuilder中。

Hi,您解决了吗?我也有同样的问题。嗨,你解决了吗?我也有同样的问题。
class Album {
  final String errorMsg ;
  final Map success;

  Album({this.errorMsg, this.success});

  factory Album.fromJson(Map<String, dynamic> json) {
    if (json.containsKey("error")){
      print(json["error"]["errorMsg"]);
      print("sfsdfdsdfsfd");
      return Album(errorMsg:json["error"]["errorMsg"].toString());
    }

    else{return Album(success:json["success"]);}
  }
}
Future<Album> createAlbum(String url, Map reqBody) async {
      final Map success={};
      final Map errorMsg={};
      final Map res={};
      final http.Response response = await http.post(
        url,
        headers: <String, String>{
          'Content-Type': 'application/json',
        },
        body: jsonEncode(reqBody),
      );

      if (response.statusCode == 200) {
        print(response.body);
        Map<dynamic, dynamic>res = json.decode(response.body);
        return Album.fromJson(json.decode(response.body));
      } else {
        throw Exception('Failed to create album.');
      }
    }