orderByChild()如果值相同，如何按第二个变量排序? [英] orderByChild() if same value, how to order by second variable?

问题描述

我使用按年龄排序的列表.如果年龄相同，我希望按名字的字母顺序对其进行排序.

I work with a list sorted by age. When there are same age, I want it to be sorted by name alphabetically.

在这种情况下，亚当应该在上方，拉姆齐应该在下方.

In this case, Adam should be above and Ramsay should be below.

我不知道如何对第二个变量使用orderByChild().

I don't know how to work with orderByChild() for the second variable.

val database = FirebaseDatabase.getInstance().getReference("Classmate").child("student").orderByChild("age")

// orderByChild("name") // for second order

推荐答案

仅使用.orderBy("atribute")时，您可以将多个链接在一起以将结果排序到最后一个顺序内.例如:.orderBy("age").orderBy("name")

When using just .orderBy("atribute") you can chain multiple ones to order the results inside the last order. For example: .orderBy("age").orderBy("name")

val database = FirebaseDatabase.getInstance().getReference("Classmate").child("student").orderByChild("age").orderBy("name")

我没有将它与orderByChild()一起使用，但我想它会以相同的方式工作.

I haven't used it with orderByChild() but i guess it would work the same way.

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