Question

我有一个模型类列表，其中有一个名为priority（String）的变量，列表中的每个项共享3个公共优先级（HIGH，LOW，MEDIUM）。我的问题是，我想使用其items priority（String）对列表进行排序。例如。所有HIGH优先级应该移到顶部，MEDIUM到中间，LOW到最后。提前谢谢。

public class Main extends Activity {
    private ArrayList<Model> listOfModel = new ArrayList<>();

    private void setData(){
        listOfModel.addAll(getDataFromServer());
        Collections.sort(listOfModel); //sort using priority 
    }
}

public class Model {
    private String name;
    private String score;
    private String priority;//HIGH,MEDIUM,LOW

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getScore() {
        return score;
    }

    public void setScore(String score) {
        this.score = score;
    }

    public String getPriority() {
        return priority;
    }

    public void setPriority(String priority) {
        this.priority = priority;
    }
}

Answer 1

创建一个自定义比较器，按顺序排列递增的优先顺序，即LOW，MEDIUM，HIGH

 Collections.sort(listOfModel, new Comparator<Model>() {
    @Override
    public int compare(Model m1, Model m2) {
        String p1 = m1.getPriority();
        String p2 = m2.getPriority();
        if(p1 == null) return 1;
        if(p2 == null) return -1; 
        if(p1.equals(p2)) return 0;
        if(p1.equals("LOW") && (p2.equals("MEDIUM") || p2.equals("HIGH")))
            return -1;
        if(p1.equals("MEDIUM") && p2.equals("HIGH"))
            return -1;
        return 1;
    }
 });

Answer 2

您可以使用以下代码对自定义对象进行排序

Collections.sort(listOfModel, new Comparator<Model>(){
    public int compare(Model m1, Model m2) {
        return m1.getPriority().compareToIgnoreCase(m2.getPriority());
    }
});

Answer 3

试试这个：

item = "priority";
mSortAttributes(item, listOfModel );

public void mSortAttributes(final String item, ArrayList<Model> sortList ){
        Collections.sort(sortList, new Comparator<Model>() {
            @Override
            public int compare(Model lhs, Model rhs) {
                int retVal = 0;
                //Ascending Order
                if (item.equals("name")) {
                    retVal = lhs.name.compareToIgnoreCase(rhs.name);
                } else if (item.equals(" score")) {
                    retVal = lhs.score.compareToIgnoreCase(rhs.score);
                } else if (item.equals("priority")) {
                    retVal = lhs.priority.compareToIgnoreCase(rhs.priority);
                } 
                return retVal;
            }
        });
    }

Answer 4

使用此Code.this工作正常

static class myComparater implements Comparator<Model> {

        @Override
        public int compare(Model o1, Model o2) {
            String p1 = o1.getPriority();
            String p2 = o2.getPriority();
            if (p1.equals(p2)) {
                return 0;
            }
            if (p1.equals("HIGH") && (p2.equals("MEDIUM") || p2.equals("LOW"))) {
                return -1;
            }
            if (p1.equals("MEDIUM") && p2.equals("LOW")) {
                return -1;
            }
            return 1;
        }
    }

Answer 5

这正在工作。使用此代码，您可以添加更多的大小写。

private static Comparator<OrderHistoryItemData> COMPARE_BY_PAYMENT = new Comparator<OrderHistoryItemData>() {
    private int map(String str) {
        switch (str) {
            case "HIGH":
                return 0;
            case "MEDIUM":
                return 1;
            case "LOW":
                return 2;
            default:
                return 3;
        }
    }

    @Override
    public int compare(String o1, String o2) {
        return map(o1) - map(o2 );
    }
};

如何使用优先级（String）Android对自定义列表进行排序

5 个答案: