Question

public class FacultiesActivity extends AppCompatActivity {
private ListView staffLlistView;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    initComponent();
    setContentView(R.layout.activity_faculties);

    FirebaseDatabase database = FirebaseDatabase.getInstance();
    DatabaseReference myRef = database.getReference("staff");


    Query mRef = myRef.child("1");


    mRef.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            try {
                Staff staff = dataSnapshot.getValue(Staff.class);
                String name =staff.getName();

                Toast.makeText(FacultiesActivity.this,name , Toast.LENGTH_LONG).show();
            }catch (Exception ex){
               // Toast.makeText(FacultiesActivity.this, ex.toString(), Toast.LENGTH_LONG).show();

            }
        }

        @Override
        public void onCancelled(DatabaseError error) {
            Toast.makeText(FacultiesActivity.this, "Error", Toast.LENGTH_LONG).
 });


    }
private void initComponent() {
    genrateId();
    registerEvents();

}

private void genrateId() {
    staffLlistView=findViewById(R.id.staffListView);
}

private void registerEvents() {
}
}

staff.java：

        package com.example.shant.kdkce.Contrrollers;

public class Staff {

private String department;
private String designation;
private String email;
private String image;
private String name;
private String qualification;

public Staff() {
}

public Staff(String department, String designation, String email, String image, String name, String qualification) {
    this.department = department;
    this.designation = designation;
    this.email = email;
    this.image = image;
    this.name = name;
    this.qualification = qualification;
}

public String getDepartment() {
    return department;
}

public void setDepartment(String department) {
    this.department = department;
}

public String getDesignation() {
    return designation;
}

public void setDesignation(String designation) {
    this.designation = designation;
}

public String getEmail() {
    return email;
}

public void setEmail(String email) {
    this.email = email;
}

public String getImage() {
    return image;
}

public void setImage(String image) {
    this.image = image;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public String getQualification() {
    return qualification;
}

public void setQualification(String qualification) {
    this.qualification = qualification;
}

}

数据库：

想要从firebase数据库中读取数据并将其显示到列表或卡中，但甚至无法从数据库中获取数据并在toast内部显示需要帮助从数据库中读取数据

在 com.example.shant.kdkce.FacultiesActivity $ 1.onDataChange（FacultiesActivity.java:43）在com.google.android.gms.internal.firebase_database.zzfc.zza（未知来源：13）在com.google.android.gms.internal.firebase_database.zzgx.zzdr（未知来源：2）在com.google.android.gms.internal.firebase_database.zzhd.run（未知来源：71）在android.os.Handler.handleCallback（Handler.java:789）在android.os.Handler.dispatchMessage（Handler.java:98）在android.os.Looper.loop（Looper.java:172）在android.app.ActivityThread.main（ActivityThread.java:6637） at java.lang.reflect.Method.invoke（Native Method）在com.android.internal.os.Zygote $ MethodAndArgsCaller.run（Zygote.java:240）在com.android.internal.os.ZygoteInit.main（ZygoteInit.java:767）

Firebase如何从以下数据库获取错误数据

0 个答案: