Question

所以我试图将一个用户的个人资料加载到一个对象中，事情就是程序确实获得了我所拥有的参考文件的所需密钥，但是当应用程序获取了Profile对象时所发生的错误getters返回null。

这是我的日志打印：

W/ClassMapper: No setter/field for -K2Hh5c8ltlwIXNO44Rp found on class 
com.example.android.firetest.models.Profiles
I/System.out: the user's id: null
D/AndroidRuntime: Shutting down VM
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.android.firetest, PID: 8546
java.lang.NullPointerException: Attempt to invoke virtual method'
java.lang.String java.lang.String.trim()' on a null object reference 
at java.lang.StringToReal.parseDouble(StringToReal.java:263)
                  at java.lang.Double.parseDouble(Double.java:301)
                  at com.example.android.firetest.Account_balance$2.onDataChange(Account_balance.java:263)

我的方法来检索用户数据：

private void loadUserdata() {
    System.out.println("entro aqui !");
    Query profileQuery = myRef.child("profiles").orderByChild("email").equalTo("jose.nieto@riagency.us").limitToFirst(1);
    profileQuery.addListenerForSingleValueEvent(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            Profiles user = dataSnapshot.getValue(Profiles.class);
            System.out.println("the user's id: "+user.getId());
            base_salary = user.getBase_salary();
            cedula = user.getId();
            //Here is where the error happens
            Double monto_quincenal = Double.parseDouble(base_salary)/2;
            primera_quincena.setText(monto_quincenal.toString());
            segunda_quincena.setText(monto_quincenal.toString());
            Account_name.setText(user.getFirst_name() +" "+ user.getLast_name());
            refOrder = myRef.child("invoices").child(year.getSelectedItem().toString())
                    .child(month.getSelectedItem().toString())
                    .orderByChild("id").equalTo(cedula);
            System.out.println("la cedula en el metodo "+cedula);

                    populateInvoiceList();

        }

        @Override
        public void onCancelled(DatabaseError databaseError) {
            System.out.println("the has been an error retrieving the user data: \n" + databaseError.getMessage());
        }
    });
}

我真的不知道为什么在下面已经分配了base_salary为空时

POJO：

public class Profiles {
private String age;
private String email;
private String name;
private String image;
private String first_name;
private String address;
private String avatar;
private String base_salary;
private String birthday_date;
private String city;
private String counrty_code;
private String dpto;
private String id;
private Boolean is_leader;
private String last_name;
private String occupation;
private String phone;
private int registered_at;
private String role;
private Boolean status;
private int updated_at;

public Profiles() {
}

public Profiles(String age, String email, String name, String first_name,
                String image, String address, String avatar, String base_salary, String counrty_code, String birthday_date,
                String city, String dpto, String id, Boolean is_leader, String occupation, String last_name,
                String phone, int registered_at, String role, Boolean status, int updated_at) {
//**
}

Firebase参考：

firetest-e5a93/profiles/-K2Hh5c8ltlwIXNO44Rp
-K2Hh5c8ltlwIXNO44Rp
address: "cra 45, calle 75b sur, int 106, edif las acasia..."
avatar: "avatar.jpg"
base_salary: "300000"
birthday_date: "1986-01-03"
city: "sabaneta"
counrty_code: "CO"
dpto: 2
email: "jose.nieto@riagency.us"
first_name: "Jose Gabriel"
has_avatar: true
id: "060514699"
interests: "PHP, Js, html, css, AngularJS, laravel, cakephp..."
is_leader: true
last_name: "Nieto Avila"
occupation: "Ing en Informatica"
phone: "3223349524"
position: "Lider Development"
registered_at: 1446643984181
role: "admin"
schedule_special: true
status: true
team_name: "Fino Code"
updated_at: 1446643984181

正如你所看到的，在Log中我们得到了相同的 Key 但是Profile对象似乎是null，有什么想法吗？

Answer 1

您的POJO中的年龄属性不在您的firebase引用中，而您的firebase引用中的team_name不在您的POJO中。

修改

哦，而且，该查询将返回一个Profiles数组，而不是一个Profile。这就是为什么它试图将该密钥设置为属性的原因。尝试获取快照的第一个孩子。

for (DataSnapshot snapshot : dataSnapshot.getChildren()) {
    Profiles profile = snapshot.getValue(Profiles.class);
    System.out.println(profile);
}

W / ClassMapper：在类上找不到* key *的setter / field

1 个答案:

修改