要在Firestore中显示创建的用户,可以遵循以下步骤:
FirebaseFirestore db = FirebaseFirestore.getInstance();
public class User {
private String name;
private String email;
public User() {
// 必须有一个空构造函数以便Firestore能够将数据反序列化为对象
}
public User(String name, String email) {
this.name = name;
this.email = email;
}
// 各个属性的getter和setter方法
}
User user = new User("John Doe", "johndoe@example.com");
db.collection("users")
.add(user)
.addOnSuccessListener(new OnSuccessListener() {
@Override
public void onSuccess(DocumentReference documentReference) {
Log.d(TAG, "用户已添加,ID:" + documentReference.getId());
}
})
.addOnFailureListener(new OnFailureListener() {
@Override
public void onFailure(@NonNull Exception e) {
Log.w(TAG, "用户添加失败", e);
}
});
db.collection("users")
.get()
.addOnSuccessListener(new OnSuccessListener() {
@Override
public void onSuccess(QuerySnapshot queryDocumentSnapshots) {
List userList = new ArrayList<>();
for (QueryDocumentSnapshot document : queryDocumentSnapshots) {
User user = document.toObject(User.class);
userList.add(user);
Log.d(TAG, "用户:" + user.getName() + ", " + user.getEmail());
}
// 在应用程序中显示用户列表
// ...
}
})
.addOnFailureListener(new OnFailureListener() {
@Override
public void onFailure(@NonNull Exception e) {
Log.w(TAG, "获取用户失败", e);
}
});
通过这些步骤,您将能够在Firestore中显示创建的用户,并将它们在应用程序中展示出来。请确保您的Android项目已经配置好Firestore。