Question

我在地图中保存产品的详细信息并添加到ArrayList＆lt;的HashMap＆LT;字符串，字符串＆gt;＆gt;并设置自定义列表适配器。我需要按价格对价值进行排序。怎么实现呢？提前谢谢。

Answer 1

请使用以下代码：

ArrayList< HashMap< String,String >> arrayList=populateArrayList();
    Collections.sort(arrayList, new Comparator<HashMap< String,String >>() {

        @Override
        public int compare(HashMap<String, String> lhs,
                HashMap<String, String> rhs) {
            // Do your comparison logic here and retrn accordingly.
            return 0;
        }
    });

Answer 2

您可以实施Comparator<Map<String, String>>或Comparator<HashMap<String, String>>

How sort an ArrayList of HashMaps holding several key-value pairs each? 很好地回答：

class MapComparator implements Comparator<Map<String, String>>{
    private final String key;

    public MapComparator(String key){
        this.key = key;
    }

    public int compare(Map<String, String> first,
                       Map<String, String> second){
        // TODO: Null checking, both for maps and values
        String firstValue = first.get(key);
        String secondValue = second.get(key);
        return firstValue.compareTo(secondValue);
    }
}

...
Collections.sort(arrayListHashMap, new MapComparator("value"));

另请参阅How to sort a Map on the values in Java?

Answer 3

您只需将其用于自定义数组列表中对象的排序，

public class MyComparator implements Comparator<MyObject> {
    @Override
    public int compare(MyObject o1, MyObject o2) {
        return o1.getYOUROBJ1STR.compareTo(o2.getYOUROBJ2STR);
    }
}

如果您仍然面临排序地图

的问题，请与我们联系

Answer 4

如果是ArrayList

的情况，可以使用comparator和Collections类一起完成

选中此link

感谢Lars vogel

Answer 5

我想你正在寻找： -

Sort ArrayList of custom Objects by property

sorting a List of Map<String, String>

希望它会帮助你......

Android：如何订购ArrayList <hashmap <string，string>＆gt;？</hashmap <string，string>

5 个答案: