java - 如何在模型中创建一个增量数字字符串值并使用 Android Studio 读取 Firebase 数据库中的值？

Question

例如。我希望我的 Firebase 数据的结构如下............

"Food" 
        -> uid 
              -> 1 - name& value
                 2 - name& value
                 3  - name& value 
                 
        -> uid 
              -> 1 - name& value 
                 2 - name& value
                 3 - name& value

我只想从 FirebaseDatabase 检索数据，而无需通过应用输入任何数据。

我如何在不破坏字符串的情况下在我的模型类中创建增量数字字符串值“1++”

并使用回收器适配器读取它作为字符串值“x”

或者有没有另一种方法来编码这个因为我还是新手

具有 ViewHolder 功能的 FirebaseRecyclerAdapter

@Override
    public void onStart() {
        super.onStart();

        FirebaseRecyclerAdapter<Ingredients, IngredientsViewHolder> firebaseRecyclerAdapter = new FirebaseRecyclerAdapter<Ingredients, IngredientsViewHolder>(
                Ingredients.class,
                R.layout.list_single_ingredients,
                IngredientsViewHolder.class,
                mDatabase

        ) {
            @Override
            protected void populateViewHolder(IngredientsViewHolder viewHolder, Ingredients model, int position) {
                viewHolder.setX(model.getX());

            }
        };
        Ingredients_list.setAdapter(firebaseRecyclerAdapter);


    }


    //ViewHolder
    public static class IngredientsViewHolder extends RecyclerView.ViewHolder {
        View m2View;

        public IngredientsViewHolder(View itemView) {
            super(itemView);


            m2View = itemView;
        }

        public void setX(String x) {
            TextView IngredientsView = (TextView) m2View.findViewById(R.id.txt_ingredients);
            IngredientsView.setText(x);

        }

    }


}

我的模型类

package Model;

/**
 * Created by Keiren on 1/4/2018.
 */

public class Ingredients {
    public String x;



    public Ingredients() {

    }
    public Ingredients(String x) {
        this.x = x;
    }


    public String getX() {return x;}

    public void setX(String x) {
        this.x = x;
    }
}

Answer 1

要解决这个问题，首先需要将 String 转换为 int，增加值，然后将 int 转换回 String，如下所示:

String one = "1";
int two = Integer.valueOf(one);
two++;
String increasedValue = String.valueOf(two);
System.out.println(increasedValue);

输出将是:2