類擴展類的適配器

Question

我有班級對象“學生”，“老師”，“工人”擴展了班級對象“人”。 現在，我想編寫一個可用於所有類的適配器。 我嘗試使用ArrayAdapter <People>但是當傳遞給Student數組時發生錯誤。 在此處輸入圖片說明

public class AdapterPeople extends ArrayAdapter<People> {
private ArrayList<People> arrPeople;
private Context context;
private LayoutInflater layoutInflater;

public AdapterPeople(@NonNull Context context, int resource, @NonNull ArrayList<People> objects) {
    super(context, resource, objects);
    this.arrPeople = objects;
    this.context = context;
    this.layoutInflater = (LayoutInflater) context.getSystemService(context.LAYOUT_INFLATER_SERVICE);
}

Answer 1

ArrayList<People>與ArrayList<Student>

這樣可以使用通配符?

public class AdapterPeople extends ArrayAdapter<People> {
    private ArrayList<? extends People> arrPeople;
    private Context context;
    private LayoutInflater layoutInflater;

    public AdapterPeople(@NonNull Context context, int resource, @NonNull ArrayList<? extends People> objects) {
        super(context, resource, objects);
        this.arrPeople = objects;
        this.context = context;
        this.layoutInflater = (LayoutInflater) context.getSystemService(context.LAYOUT_INFLATER_SERVICE);
    }

證明

泛型，繼承和子類型

解決方案參考

上界通配符