Android:类 ContactsAdapter 中的构造函数 ContactsAdapter 不能应用于给定类型

Question

我正在尝试用 ArrayList 填充 ListView

这是我的代码:

ArrayList<Contact> results = mapper.readValue(response.toString(),
                                new TypeReference<ArrayList<Contact>>() { } );//results are coming OK

                        ContactsAdapter adapter = new ContactsAdapter(this, R.layout.list_view_items, results);//error is here

这是我的自定义适配器类，及其各自的构造函数:

public class ContactsAdapter extends ArrayAdapter<Contact> {

    ArrayList<Contact> contactList = new ArrayList<>();

    public ContactsAdapter(Context context, int textViewResourceId, ArrayList<Contact> objects) {
        super(context, textViewResourceId, objects);
        contactList = objects;
    }

    @Override
    public int getCount() {
        return super.getCount();
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View v = convertView;
        LayoutInflater inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        v = inflater.inflate(R.layout.list_view_items, null);
        TextView contactTextView = (TextView) v.findViewById(R.id.contactTextView);
        TextView phoneTextView = (TextView) v.findViewById(R.id.phoneTextView);
        ImageView imageView = (ImageView) v.findViewById(R.id.smallImageView);
        contactTextView.setText(contactList.get(position).getName());
        phoneTextView.setText(contactList.get(position).getPhone().toString());
        //imageView.setImageResource(animalList.get(position).getAnimalImage());
        return v;
    }

}

错误:

Error:(58, 51) error: constructor ContactsAdapter in class ContactsAdapter cannot be applied to given types; required: Context,int,ArrayList found: >,int,ArrayList reason: actual argument > cannot be converted to Context by method invocation conversion

我的数据是从一个 jSON 中抓取的，它被声明为 ArrayList。我已经尝试了一些方法，比如修改构造函数，但我没有让它工作，我被卡住了。

提前致谢!

Answer 1

Error:(58, 51) error: constructor ContactsAdapter in class ContactsAdapter cannot be applied to given types; required: Context,int,ArrayList<Contact> found: <anonymous Listener<JSONArray>>,int,ArrayList<Contact> reason: actual argument <anonymous Listener<JSONArray>> cannot be converted to Context by method invocation conversion

你的 Adapter 构造函数调用显然是在一个匿名类中，所以 this 指的是那个匿名类，而不是你需要的 Context第一个参数。如果该代码在 Activity 中，只需将 Activity 名称添加到 this 之前；例如，MyActivity.this。

ContactsAdapter adapter = new ContactsAdapter(MyActivity.this,
                                              R.layout.list_view_items,
                                              results);