Question

我在计算收入的SUM时遇到问题

public void onChildAdded(DataSnapshot dataSnapshot, String s) {
    String transpo = String.valueOf(dataSnapshot.child("Income").getValue());
    //int amount = Integer.parseInt(String.valueOf(dataSnapshot.child("amount").getValue()));
    Map<String, String> amount = (Map<String, String>)dataSnapshot.child("amount").getValue();

//该模型称为收入模型

GenericTypeIndicator<HashMap<String, Income>> t = new 

    GenericTypeIndicator<HashMap<String, Income>>() {};
            HashMap<String, Income> expenses = (HashMap<String, Income>) dataSnapshot.child("Income").getValue();

//遍历它以获得总和

double sum = 0;
            for(HashMap.Entry<String, Income> entry : expenses.entrySet())
            {
                sum += entry.getValue().getIncome();
            }

//现在有你的总和

Log.d(TAG,"Sum= " + sum);
                txt_tzt.setText(transpo);
                txtIncome.setText(String.valueOf(sum));
            }

这是我的模特

package Model;

public class Income {




    public String getDescription() {
        return Description;
    }

    public void setDescription(String description) {
        Description = description;
    }

    public Integer getIncome() {
        return Income;
    }

    public void setIncome(Integer income) {
        Income = income;
    }

    public String getOrganisations() {
        return Organisations;
    }

    public void setOrganisations(String organisations) {
        Organisations = organisations;
    }

    public String getAccount() {
        return Account;
    }

    public void setAccount(String account) {
        Account = account;
    }

    public String getFirekey() {
        return firekey;
    }

    public void setFirekey(String firekey) {
        this.firekey = firekey;
    }

//我希望收入总额将值传递给hashmap循环并添加新值

 private Integer Income;
    private String  Description;
    private String  Organisations;
    private String  Account;
     private String firekey;
    public Income(Integer  Income,String  Description,String Organisations,String Account,String firekey){

        this.Income=Income;
        this.Description=Description;
        this.Organisations=Organisations;
        this.Account=Account;

        this.firekey=firekey;

    }

}

Answer 1

使用Value事件侦听器

addValueEventListener(new ValueEventListener() {

            @Override
            public void onDataChange(DataSnapshot snapshot) {
                int transpo = 0;
                for (DataSnapshot postSnapshot : snapshot.getChildren()) {
                  dreff.child("income");
                    Income income = postSnapshot.getValue(Income.class);
                    transpo += income.getIncome();


                }

让我知道Macharia是怎么回事

获取儿童收入中儿童金额的Firebase Sum

1 个答案: