Java 在Android中从Firestore检索子集合数据

尝试单击RecyclerView时，我无法从子集合“日记”中检索数据。我想要的是，当我点击RecyclerView时，它将显示存储在“日记”中的数据。我的代码有什么问题

RecyclerView Java代码：

private void setUpRecyclerView() {
    fStore = FirebaseFirestore.getInstance();
    FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();
    Query query = fStore.collection("Users").document(user.getUid()).collection("Diary").orderBy("Date", Query.Direction.ASCENDING);

    FirestoreRecyclerOptions<ModelClass> options = new FirestoreRecyclerOptions.Builder<ModelClass>()
            .setQuery(query, ModelClass.class)
            .build();

    adapters = new CustomAdapter(options,this);

    adapters.startListening();
    recyclerView.setLayoutManager(new LinearLayoutManager(this));
    recyclerView.setAdapter(adapters);

    new ItemTouchHelper(new ItemTouchHelper.SimpleCallback(0,
            ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT) {
        @Override
        public boolean onMove(@NonNull RecyclerView recyclerView, @NonNull RecyclerView.ViewHolder viewHolder, @NonNull RecyclerView.ViewHolder target) {
            return false;
        }

        @Override
        public void onSwiped(@NonNull RecyclerView.ViewHolder viewHolder, int direction) {
            adapters.deleteItem(viewHolder.getAdapterPosition());
        }
    }).attachToRecyclerView(recyclerView);


}

@Override
public void onItemClick(final DocumentSnapshot snapshot, int position) {
    final ModelClass diary = snapshot.toObject(ModelClass.class);
    String id = snapshot.getId();
   startActivity(new Intent(diary_user.this,onClickRecyclerViewDiary_user.class));
    Toast.makeText(diary_user.this,"Position: " + position + "ID: " + id,Toast.LENGTH_SHORT).show();

}

check.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            FirebaseUser user = fAuth.getCurrentUser();
            String uid = user.getUid();
            String id = fStore.collection("Users").document(user.getUid()).collection("Diary").document().getId();
            DocumentReference df = fStore.collection("Users").document(user.getUid()).collection("Diary").document(id);
            Map<String, Object> diaryInfo = new HashMap<>();
            diaryInfo.put("Symptom", symptom.getEditText().getText().toString());
            diaryInfo.put("Note", note.getEditText().getText().toString());
            diaryInfo.put("Date", dateButton.getText().toString());
            diaryInfo.put("ID",id);

            SimpleDateFormat tf = new SimpleDateFormat("hh:mm a");
            String currentTime = tf.format(Calendar.getInstance().getTime());
            time.setText(currentTime);
            diaryInfo.put("Time", time.getText().toString());

            feeling = spinner.getSelectedItem().toString();
            diaryInfo.put("Feeling", feeling);

            df.set(diaryInfo).addOnSuccessListener(new OnSuccessListener() {
                @Override
                public void onSuccess(Object o) {
                    Toast.makeText(add_diary_user.this, "Data successfully stored", Toast.LENGTH_SHORT).show();
                    startActivity(new Intent(add_diary_user.this, diary_user.class));
                    finish();
                }
            }).addOnFailureListener(new OnFailureListener() {
                @Override
                public void onFailure(@NonNull Exception e) {
                    Toast.makeText(add_diary_user.this, e.toString(), Toast.LENGTH_SHORT).show();
                }
            });

        }
    });

private void getDiary() {
    fStore = FirebaseFirestore.getInstance();
    FirebaseUser user = fAuth.getCurrentUser();
    String id = fStore.collection("Users").document(user.getUid()).collection("Diary").document().getId();
    fStore.collection("Users").document(user.getUid()).collection("Diary");
            diary.whereEqualTo("ID", id)
            .get()
            .addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
                @Override
                public void onComplete(@NonNull Task<QuerySnapshot> task) {
                    if (task.isSuccessful()) {
                        for (DocumentSnapshot document : task.getResult()) {
                            // Do something with your retrieved documents
                            dateButton.setText((CharSequence) document.getString("Date"));
                            note.getEditText().setText((CharSequence) document.getString("Note"));
                            symptom.getEditText().setText((CharSequence) document.getString("Symptom"));
                        }
                    }
                }
            });
}

private void setuprecyclererview（）{
fStore=FirebaseFirestore.getInstance（）；
FirebaseUser=FirebaseAuth.getInstance（）.getCurrentUser（）；
Query Query=fStore.collection（“用户”）.document（user.getUid（））.collection（“日记”）.orderBy（“日期”，Query.Direction.升序）；
FirestoreRecyclerOptions选项=新建FirestoreRecyclerOptions.Builder（）
.setQuery（查询，ModelClass.class）
.build（）；
adapters=新的CustomAdapter（选项，此选项）；
adapters.startListening（）；
recyclerView.setLayoutManager（新的LinearLayoutManager（本））；
recyclerView.setAdapter（适配器）；
新建ItemTouchHelper（新建ItemTouchHelper.SimpleCallback（0，
ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT）{
@凌驾
公共布尔onMove（@NonNull RecyclerView RecyclerView，@NonNull RecyclerView.ViewHolder ViewHolder，@NonNull RecyclerView.ViewHolder target）{
返回false；
}
@凌驾
公共void onsweed（@NonNull RecyclerView.ViewHolder ViewHolder，int-direction）{
deleteItem（viewHolder.getAdapterPosition（））；
}
}).attachToRecyclerView（recyclerView）；
}
@凌驾
public void onItemClick（最终文档快照快照，int位置）{
最终模型类日志=snapshot.toObject（ModelClass.class）；
String id=snapshot.getId（）；
startActivity（新的意图（日记用户。这个，onClickRecycleServiceWiddiary用户。类））；
Toast.makeText（日记\用户。此，“位置：+Position+”ID:+ID，Toast.LENGTH\短）。show（）；
}

存储数据Java代码：

private void setUpRecyclerView() {
    fStore = FirebaseFirestore.getInstance();
    FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();
    Query query = fStore.collection("Users").document(user.getUid()).collection("Diary").orderBy("Date", Query.Direction.ASCENDING);

    FirestoreRecyclerOptions<ModelClass> options = new FirestoreRecyclerOptions.Builder<ModelClass>()
            .setQuery(query, ModelClass.class)
            .build();

    adapters = new CustomAdapter(options,this);

    adapters.startListening();
    recyclerView.setLayoutManager(new LinearLayoutManager(this));
    recyclerView.setAdapter(adapters);

    new ItemTouchHelper(new ItemTouchHelper.SimpleCallback(0,
            ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT) {
        @Override
        public boolean onMove(@NonNull RecyclerView recyclerView, @NonNull RecyclerView.ViewHolder viewHolder, @NonNull RecyclerView.ViewHolder target) {
            return false;
        }

        @Override
        public void onSwiped(@NonNull RecyclerView.ViewHolder viewHolder, int direction) {
            adapters.deleteItem(viewHolder.getAdapterPosition());
        }
    }).attachToRecyclerView(recyclerView);


}

@Override
public void onItemClick(final DocumentSnapshot snapshot, int position) {
    final ModelClass diary = snapshot.toObject(ModelClass.class);
    String id = snapshot.getId();
   startActivity(new Intent(diary_user.this,onClickRecyclerViewDiary_user.class));
    Toast.makeText(diary_user.this,"Position: " + position + "ID: " + id,Toast.LENGTH_SHORT).show();

}

check.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            FirebaseUser user = fAuth.getCurrentUser();
            String uid = user.getUid();
            String id = fStore.collection("Users").document(user.getUid()).collection("Diary").document().getId();
            DocumentReference df = fStore.collection("Users").document(user.getUid()).collection("Diary").document(id);
            Map<String, Object> diaryInfo = new HashMap<>();
            diaryInfo.put("Symptom", symptom.getEditText().getText().toString());
            diaryInfo.put("Note", note.getEditText().getText().toString());
            diaryInfo.put("Date", dateButton.getText().toString());
            diaryInfo.put("ID",id);

            SimpleDateFormat tf = new SimpleDateFormat("hh:mm a");
            String currentTime = tf.format(Calendar.getInstance().getTime());
            time.setText(currentTime);
            diaryInfo.put("Time", time.getText().toString());

            feeling = spinner.getSelectedItem().toString();
            diaryInfo.put("Feeling", feeling);

            df.set(diaryInfo).addOnSuccessListener(new OnSuccessListener() {
                @Override
                public void onSuccess(Object o) {
                    Toast.makeText(add_diary_user.this, "Data successfully stored", Toast.LENGTH_SHORT).show();
                    startActivity(new Intent(add_diary_user.this, diary_user.class));
                    finish();
                }
            }).addOnFailureListener(new OnFailureListener() {
                @Override
                public void onFailure(@NonNull Exception e) {
                    Toast.makeText(add_diary_user.this, e.toString(), Toast.LENGTH_SHORT).show();
                }
            });

        }
    });

private void getDiary() {
    fStore = FirebaseFirestore.getInstance();
    FirebaseUser user = fAuth.getCurrentUser();
    String id = fStore.collection("Users").document(user.getUid()).collection("Diary").document().getId();
    fStore.collection("Users").document(user.getUid()).collection("Diary");
            diary.whereEqualTo("ID", id)
            .get()
            .addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
                @Override
                public void onComplete(@NonNull Task<QuerySnapshot> task) {
                    if (task.isSuccessful()) {
                        for (DocumentSnapshot document : task.getResult()) {
                            // Do something with your retrieved documents
                            dateButton.setText((CharSequence) document.getString("Date"));
                            note.getEditText().setText((CharSequence) document.getString("Note"));
                            symptom.getEditText().setText((CharSequence) document.getString("Symptom"));
                        }
                    }
                }
            });
}

check.setOnClickListener（新视图.OnClickListener（）{
@凌驾
公共void onClick（视图v）{
FirebaseUser=fAuth.getCurrentUser（）；
字符串uid=user.getUid（）；
字符串id=fStore.collection（“用户”）.document（user.getUid（））.collection（“日记”）.document（）.getId（）；
DocumentReference df=fStore.collection（“用户”）.document（user.getUid（））.collection（“日记”）.document（id）；
Map diaryInfo=newhashmap（）；
put（“症状”，症状.getEditText（）.getText（）.toString（））；
put（“Note”，Note.getEditText（）.getText（）.toString（））；
put（“Date”，dateButton.getText（）.toString（））；
diaryInfo.put（“ID”，ID）；
SimpleDataFormat tf=新的SimpleDataFormat（“hh:mm a”）；
字符串currentTime=tf.format（Calendar.getInstance（）.getTime（））；
time.setText（当前时间）；
put（“Time”，Time.getText（）.toString（））；
feeling=spinner.getSelectedItem（）.toString（）；
把（“感觉”，感觉）；
addOnSuccessListener（新的OnSuccessListener（））{
@凌驾
成功时的公共无效（对象o）{
Toast.makeText（添加_dialog_user.this，“数据成功存储”，Toast.LENGTH_SHORT.show（）；
startActivity（新的意图（添加日志用户.this，日志用户.class））；
完成（）；
}
}).addOnFailureListener（新的OnFailureListener（）{
@凌驾
public void onFailure（@NonNull异常e）{
Toast.makeText（添加用户日志，例如toString（），Toast.LENGTH\u SHORT）.show（）；
}
});
}
});

检索Java代码中的数据：

private void setUpRecyclerView() {
    fStore = FirebaseFirestore.getInstance();
    FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();
    Query query = fStore.collection("Users").document(user.getUid()).collection("Diary").orderBy("Date", Query.Direction.ASCENDING);

    FirestoreRecyclerOptions<ModelClass> options = new FirestoreRecyclerOptions.Builder<ModelClass>()
            .setQuery(query, ModelClass.class)
            .build();

    adapters = new CustomAdapter(options,this);

    adapters.startListening();
    recyclerView.setLayoutManager(new LinearLayoutManager(this));
    recyclerView.setAdapter(adapters);

    new ItemTouchHelper(new ItemTouchHelper.SimpleCallback(0,
            ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT) {
        @Override
        public boolean onMove(@NonNull RecyclerView recyclerView, @NonNull RecyclerView.ViewHolder viewHolder, @NonNull RecyclerView.ViewHolder target) {
            return false;
        }

        @Override
        public void onSwiped(@NonNull RecyclerView.ViewHolder viewHolder, int direction) {
            adapters.deleteItem(viewHolder.getAdapterPosition());
        }
    }).attachToRecyclerView(recyclerView);


}

@Override
public void onItemClick(final DocumentSnapshot snapshot, int position) {
    final ModelClass diary = snapshot.toObject(ModelClass.class);
    String id = snapshot.getId();
   startActivity(new Intent(diary_user.this,onClickRecyclerViewDiary_user.class));
    Toast.makeText(diary_user.this,"Position: " + position + "ID: " + id,Toast.LENGTH_SHORT).show();

}

check.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            FirebaseUser user = fAuth.getCurrentUser();
            String uid = user.getUid();
            String id = fStore.collection("Users").document(user.getUid()).collection("Diary").document().getId();
            DocumentReference df = fStore.collection("Users").document(user.getUid()).collection("Diary").document(id);
            Map<String, Object> diaryInfo = new HashMap<>();
            diaryInfo.put("Symptom", symptom.getEditText().getText().toString());
            diaryInfo.put("Note", note.getEditText().getText().toString());
            diaryInfo.put("Date", dateButton.getText().toString());
            diaryInfo.put("ID",id);

            SimpleDateFormat tf = new SimpleDateFormat("hh:mm a");
            String currentTime = tf.format(Calendar.getInstance().getTime());
            time.setText(currentTime);
            diaryInfo.put("Time", time.getText().toString());

            feeling = spinner.getSelectedItem().toString();
            diaryInfo.put("Feeling", feeling);

            df.set(diaryInfo).addOnSuccessListener(new OnSuccessListener() {
                @Override
                public void onSuccess(Object o) {
                    Toast.makeText(add_diary_user.this, "Data successfully stored", Toast.LENGTH_SHORT).show();
                    startActivity(new Intent(add_diary_user.this, diary_user.class));
                    finish();
                }
            }).addOnFailureListener(new OnFailureListener() {
                @Override
                public void onFailure(@NonNull Exception e) {
                    Toast.makeText(add_diary_user.this, e.toString(), Toast.LENGTH_SHORT).show();
                }
            });

        }
    });

private void getDiary() {
    fStore = FirebaseFirestore.getInstance();
    FirebaseUser user = fAuth.getCurrentUser();
    String id = fStore.collection("Users").document(user.getUid()).collection("Diary").document().getId();
    fStore.collection("Users").document(user.getUid()).collection("Diary");
            diary.whereEqualTo("ID", id)
            .get()
            .addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
                @Override
                public void onComplete(@NonNull Task<QuerySnapshot> task) {
                    if (task.isSuccessful()) {
                        for (DocumentSnapshot document : task.getResult()) {
                            // Do something with your retrieved documents
                            dateButton.setText((CharSequence) document.getString("Date"));
                            note.getEditText().setText((CharSequence) document.getString("Note"));
                            symptom.getEditText().setText((CharSequence) document.getString("Symptom"));
                        }
                    }
                }
            });
}

private void getDiary（）{
fStore=FirebaseFirestore.getInstance（）；
FirebaseUser=fAuth.getCurrentUser（）；
字符串id=fStore.collection（“用户”）.document（user.getUid（））.collection（“日记”）.document（）.getId（）；
fStore.collection（“用户”）.document（user.getUid（））.collection（“日记”）；
日记。何处为“ID”，ID）
.get（）
.addOnCompleteListener（新的OnCompleteListener（）{
@凌驾
未完成的公共void（@NonNull任务）{
if（task.issusccessful（））{
对于（DocumentSnapshot文档：task.getResult（））{
//对检索到的文档执行一些操作
dateButton.setText（（CharSequence）document.getString（“日期”）；
note.getEditText（）.setText（（CharSequence）document.getString（“note”）；
symptom.getEditText（）.setText（（CharSequence）document.getString（“症状”）；
}
}
}
});
}

数据库结构：

输出：

---

我认为您代码中的问题在于这一行：

String id = fStore.collection("Users").document(user.getUid()).collection("Diary").document().getId();

---

使用

.document（）.getId（）的位置

但不指定所需的文档，这会使

id

不具有预期值，因此在稍后执行时使用该值的比较中不会得到任何结果。若要修复此问题，您需要将此Id存储在某个位置，并将其作为参数传递给

getDiary（）

函数或类似的函数。

此代码中到底有什么不符合预期的工作方式？我的代码没有任何错误，但数据不会显示出来。我已经编辑了我的帖子，现在你可以看到我的输出了。输出1显示RecyclerView，输出2显示当我点击其中一个时，它不会显示数据。所以你是从一个活动转到另一个活动，对吗？是的，它是…..感谢你一直帮助我，现在我知道了。现在我知道问题出在哪里，非常感谢。