Question

参考以下代码。我想知道为什么我需要放入一个对象而不是字符串中的所有对象。此代码来自自定义ListView适配器。

public ArrayAdapter (Context context, int textViewResourceId, T[] objects)

工作正常

public ListViewAdapter(Context context, String[] first, String[] second, String[] third) {
            super(context, R.layout.listview_item, first);
            this.context = context;
            this.first = first;
            this.second = second;
            this.third = third;
        }

如果我这样做会出错。

public ListViewAdapter(Context context, String[] first, String[] second, String[] third) {
        super(context, R.layout.listview_item, first, second, third);
        this.context = context;
        this.first = first;
        this.second = second;
        this.third = third;
    }

错误：构造函数ArrayAdapter（Context，int，String []，String []，String []）未定义

原始资料

public class ListViewAdapter extends ArrayAdapter<String> {
    Context context;
    String[] first;
    String[] second;
    String[] third;
    LayoutInflater inflater;

    public ListViewAdapter(Context context, String[] first, String[] second, String[] third) {
        super(context, R.layout.listview_item, first);
        this.context = context;
        this.first = first;
        this.second = second;
        this.third = third;
    }

Answer 1

您应该阅读Java中inheritance的原理。您的课程正在延长ArrayAdapter。

如果你看一下它，你会发现没有为这个类定义ArrayAdapter(Context, int, String[], String[], String[])类型的构造函数。

这就是你无法做super(context, R.layout.listview_item, first, second, third);

的原因

ListView的公共ArrayAdapter

1 个答案: