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Android 从firebase检索所有值并将其放入TextView_Android_Firebase_Firebase Realtime Database_Textview - Fatal编程技术网

Android 从firebase检索所有值并将其放入TextView

Android 从firebase检索所有值并将其放入TextView,android,firebase,firebase-realtime-database,textview,Android,Firebase,Firebase Realtime Database,Textview,我想检索Dosa和Dosa2并将其放入文本视图中。 下面是我尝试过的代码,但我只能检索Dosa2 mMessagesDatabaseReference = mFirebaseDatabase.getReference("messages"); // Attach a listener to read the data at our posts reference mMessagesDatabaseReference.addValueEventListener(new Value

我想检索Dosa和Dosa2并将其放入文本视图中。 下面是我尝试过的代码,但我只能检索Dosa2

mMessagesDatabaseReference = mFirebaseDatabase.getReference("messages");

// Attach a listener to read the data at our posts reference
        mMessagesDatabaseReference.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                for (DataSnapshot postSnapshot: dataSnapshot.getChildren()) {
                    Food food = postSnapshot.getValue(Food.class);
                    foodnameTextView.setText(food.getFoodname()+"\n");
                }}

            @Override
            public void onCancelled(DatabaseError databaseError) {
                System.out.println("The read failed: " + databaseError.getCode());
            }
        });

因为您每次都在循环中设置textview。请执行以下操作: 在顶部初始化变量并在循环中追加文本,然后将其设置为textview

 mMessagesDatabaseReference = mFirebaseDatabase.getReference("messages");

    // Attach a listener to read the data at our posts reference
            String foodName="";
            mMessagesDatabaseReference.addValueEventListener(new ValueEventListener() {
                @Override
                public void onDataChange(DataSnapshot dataSnapshot) {
                    for (DataSnapshot postSnapshot: dataSnapshot.getChildren()) {
                        Food food = postSnapshot.getValue(Food.class);
                        foodName+=food.getFoodname()+"\n";

                    }
                    foodnameTextView.setText(foodName);
                }

                @Override
                public void onCancelled(DatabaseError databaseError) {
                    System.out.println("The read failed: " + databaseError.getCode());
                }
            });

非常感谢,我犯了一个多么愚蠢的错误