Question

我是Android新手。

这个问题可能是一个基本问题。

但是我这四天都在苦苦挣扎。请帮我。

我正在制作横向列表视图，用于提供博客中几个类别的内容。

（与Pulse新闻应用程序类似的界面）

我得到了水平列表视图的开源，我正在修改它。

此代码为CustomArrayAdapter.java。

但是当我尝试写super()时;在构造函数中，它会产生如下错误：

The constructor ArrayAdapter<ArrayList<HashMap<String, String>>>(Context, int, ArrayList<HashMap<String, String>>) is undefined

eclipse建议这样：

Remove argument to match 'ArrayAdapter<ArrayList<HashMap<String, String>>>(Context, int)'

我不知道这个（Context，int）参数来自哪里。

请检查以下CustomArrayAdapter.java中的错误：

package com.xxxx.xxxxxxxxx;

import java.util.ArrayList;
import java.util.HashMap;

import android.content.Context;
import android.graphics.Color;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;

/** An array adapter that knows how to render views when given CustomData classes */
public class CustomArrayAdapter extends ArrayAdapter<ArrayList<HashMap<String, String>>> {
    private Context context;
    private ArrayList<HashMap<String, String>> data;
    private int viewId;

    private LayoutInflater mInflater;

    public CustomArrayAdapter(Context c, int textViewResourceId, ArrayList<HashMap<String, String>> d) {
        super(c, textViewResourceId, d);

        this.context = c;
        this.viewId = textViewResourceId;
        this.data = d; 
    }

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

    /*
     * We are overriding the getView method here - this is what defines how each
     * list item will look.
     */
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {         
        // Assign the view we are converting to a local variable
        View vi = convertView;
        Holder holder;      

        if (convertView == null) {

            // Inflate the view since it does not exist
            if (vi == null) {
                mInflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                vi = mInflater.inflate(R.layout.custom_data_view, null);
            }

            /*
             * Recall that the variable position is sent in as an argument to this method.
             * The variable simply refers to the position of the current object in the list. (The ArrayAdapter
             * iterates through the list we sent it)
             * 
             * Therefore, i refers to the current Item object.
             */

            // This is how you obtain a reference to the TextViews.
            // These TextViews are created in the XML files we defined.

            // Create and save off the holder in the tag so we get quick access to inner fields
            // This must be done for performance reasons

            holder = new Holder();
            holder.textView = (TextView) vi.findViewById(R.id.title_view);
            holder.imageView = (ImageView) vi.findViewById(R.id.thumbnail_view);

            vi.setTag(holder);                                  

        } else {
            holder = (Holder) vi.getTag();
        }

        // check to see if each individual textview is null.
        // if not, assign some text!
        // Populate the text 

        HashMap<String, String> currentData = new HashMap<String, String>();
        currentData = data.get(position);

        if (currentData != null) {
            holder.textView.setText(currentData.get(MainActivity.KEY_TITLE));
            holder.imageLoader = new ImageLoader(context.getApplicationContext());    
            holder.imageLoader.DisplayImage(currentData.get(MainActivity.KEY_THUMBNAIL), holder.imageView);
        }       

        // Set the color
        vi.setBackgroundColor(Color.DKGRAY);
        return vi;
    }

    /** View holder for the views we need access to */
    private static class Holder {
        public TextView textView;
        public ImageView imageView;
        public ImageLoader imageLoader;
    }
}

Answer 1

应该是：

public class CustomArrayAdapter extends ArrayAdapter<HashMap<String, String>>

Answer 2

编译器告诉你改变这个

super(c, textViewResourceId, d);

到

super(c, textViewResourceId);

构造函数ArrayAdapter <arraylist <hashmap <string，string =“”>＆gt;＆gt;（Context，int，ArrayList <hashmap <string，string =“”>＆gt;）未定义</hashmap <string，> </arraylist <散列映射<串，>

2 个答案: