Question

我想根据子节点的特定键访问用户中的子项，并且已经在我的函数getcount（）中传递了该键，但是当我使用该引用键访问用户时，它会显示com.google.firebase .database.DatabaseException：无法将java.lang.Long类型的值转换为String。

我使用了以下代码，但无法正常工作

  private void getCount(final String referalKey) {
    DatabaseReference myref=FirebaseDatabase.getInstance().getReference().child("users").child(referalKey);
    myref.addListenerForSingleValueEvent(new ValueEventListener() {
        @Override
        public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
            user u=dataSnapshot.getValue(user.class);
            Toast.makeText(Home.this,u.getCount(),Toast.LENGTH_SHORT).show();

        }

        @Override
        public void onCancelled(@NonNull DatabaseError databaseError) {

        }
    });



}

我的用户模型类

public class user {
      public String name;
      public String phone;
      public String refphone;
      public String address;
      public String count;

    public user() {
        // Default constructor required for calls to DataSnapshot.getValue(User.class)
    }

    public String getCount() {
        return count;
    }

    public void setCount(String count) {
        this.count = count;
    }

    public user(String name, String phone, String refphone, String address, String count) {
        this.name = name;
        this.phone = phone;
        this.refphone = refphone;
        this.address = address;
        this.count = count;
    }

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

    public void setPhone(String phone) {
        this.phone = phone;
    }

    public void setRefphone(String refphone) {
        this.refphone = refphone;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public String getName() {
        return name;
    }

    public String getPhone() {
        return phone;
    }

    public String getRefphone() {
        return refphone;
    }

    public String getAddress() {
        return address;
    }
}

Answer 1

正如我在您的数据库中看到的那样，在"中的一个文档中截取了您的数量和电话号码，而在另外一个文档中却很长。手动更改

Answer 2

将您的phone和count属性从String更改为long，因为您的数据库将其包含为long

public class user {
    public String name;
    public long phone;
    public String refphone;
    public String address;
    public long count;

    public user() {
        // Default constructor required for calls to DataSnapshot.getValue(User.class)
    }

    public long getCount() {
        return count;
    }

    public void setCount(long count) {
        this.count = count;
    }

    public user(String name, long phone, String refphone, String address, long count) {
        this.name = name;
        this.phone = phone;
        this.refphone = refphone;
        this.address = address;
        this.count = count;
    }

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

    public void setPhone(long phone) {
        this.phone = phone;
    }

    public void setRefphone(String refphone) {
        this.refphone = refphone;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public String getName() {
        return name;
    }

    public long getPhone() {
        return phone;
    }

    public String getRefphone() {
        return refphone;
    }

    public String getAddress() {
        return address;
    }
}

在Firebase数据库中读取子级

2 个答案: