Question

这是逻辑错误，我在Bundler could not find compatible versions for gem "activerecord": In Gemfile: annotate was resolved to 2.7.4, which depends on activerecord (< 6.0, >= 3.2) delayed_job_active_record was resolved to 4.1.3, which depends on activerecord (< 5.3, >= 3.0) kaminari was resolved to 1.1.1, which depends on kaminari-activerecord (= 1.1.1) was resolved to 1.1.1, which depends on activerecord paper_trail was resolved to 10.2.0, which depends on activerecord (< 6.1, >= 4.2) rails (= 6.0.0.beta1) was resolved to 6.0.0.beta1, which depends on activerecord (= 6.0.0.beta1) rails-erd was resolved to 1.5.2, which depends on activerecord (>= 3.2) activeadmin-select2 was resolved to 0.1.8, which depends on activeadmin was resolved to 1.4.3, which depends on ransack (>= 1.8.7) was resolved to 2.1.1, which depends on activerecord (>= 5.0) seed_dump was resolved to 3.3.1, which depends on activerecord (>= 4) state_machines-activerecord was resolved to 0.5.2, which depends on activerecord (< 6.0, >= 4.1) textacular was resolved to 5.1.0, which depends on activerecord (< 6.0, >= 5.0)下检索7 儿童数，但是输出中只有四个儿童数

stocks

我使用OUTPUT: "4 Rubber Duck"，并且输出不是全部的橡皮鸭。它应该总共textView.setText(allDuck " Rubber Duck");个输出而不是四个。这是有问题的数据结构和代码，但我不知道问题出在哪里，能否请您帮我找到逻辑错误：我认为，firebase混淆了我的uid的读取，

。

Database
    DuckCompany
       SALES
          WireHouse
             Inventory
                  RubberDUCK
                     DuckID
                        axRGznal3nkhxsDax // this is uid
                                stocks
                                   -LEeeeeeeeeeeeeeeee  // this is id 
                                                redValue:"71"
                                   -LFffffffffffffffff 
                                                redValue:"71"
                                   -LGggggggggggggggg 
                                                redValue:"71"
                        cpsGGGGNxQQQOWqh
                                stocks 
                                   -LAaaaaaaaaaaaaaa 
                                                redValue:"71"
                                   -LBbbbbbbbbbbbbbb 
                                                redValue:"71"
                                   -LCccccccccccccc 
                                                redValue:"71"
                                   -LDddddddddddddd
                                                redValue:"71"

Answer 1

您要遍历DuckID下的所有（2）键，并为每个键获取stock下的子项数量，但是您并没有在任何地方添加这些数量，只是覆盖了以前的值。

尝试以下方法：

    public void onDataChange(@NonNull DataSnapshot dataSnapshot) {

        int allDuck = 0;

        for (DataSnapshot uids : dataSnapshot.child("DuckID").getChildren()) {

            String uidKeys = uids.getKey();

            if (uidKeys != null) {
                allDuck += (int) dataSnapshot.child("DuckID").child(uidKeys).child("stocks").getChildrenCount();                            
            }
        }
        textView.setText(allDuck " Rubber Duck");
    }

无法检索子项下的所有计数

1 个答案: