无法将类型为java.lang.Boolean的对象转换为错误Android

Question

我正在从Firebase中提取Boolean。但是，提取数据时出现Can't convert object of type java.lang.Boolean错误。

如何提取Boolean数据？

List<Product> productList;
List<Boolean> productListStates;

public class MainActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {
    DatabaseReference mDatabase = FirebaseDatabase.getInstance().getReference();
    final DatabaseReference ref = mDatabase.child("0").child("states").child("001");
    ref.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot snapshot) {
            Product p = snapshot.getValue(Product.class);
            productListStates.add(p.getStates());
        }
        @Override
        public void onCancelled(DatabaseError databaseError) {
        }
    });
}

产品类别：

public class Product {

    private String places;
    private String time;
    private String title;
    private String id;
    private boolean States;

    public Product(){
    }

    public Product(String places, String time, String title, String id, boolean States) {
        this.places = places;
        this.time = time;
        this.title = title;
        this.id = id;
        this.States = States;
    }

    public String getplaces() {
        return places;
    }

    public String gettime() {
        return time;
    }

    public String gettitle() {
        return title;
    }

    public String getid() {
        return id;
    }

    public boolean getStates() {
        return States;
    }
}

Answer 1

正如我在您的架构中看到的那样，在states节点下没有Product类型的对象，只是布尔类型的属性。这就是为什么您会收到该错误。要解决此问题，请使用以下代码行：

DatabaseReference mDatabase = FirebaseDatabase.getInstance().getReference();
final DatabaseReference ref = mDatabase.child("0").child("states").child("001");
ref.addValueEventListener(new ValueEventListener() {
    @Override
    public void onDataChange(DataSnapshot snapshot) {
        booblean b = snapshot.getValue(Boolean.class);
        Log.d(TAG, String.valueOf(b));
    }
    @Override
    public void onCancelled(DatabaseError databaseError) {
    }
});

}

logcat中的结果将是：

true