无法在listview

Question

我有问题是我无法在listview中显示图像，我使用Android JSON Parsing Using Volley来显示带有图像的listview。项目的信息成功显示，但图像不成功。我卡在那里仍然找不到解决方案。

这是itemRequest类

public class itemRequest extends StringRequest{
private static final String ITEM_REQUEST_URL = "http://XXXXXXXXXXXXX.php";
private Map<String, String> params;

public itemRequest(String userID, String sessionID, Response.Listener<String> listener) {
    super(Request.Method.POST, ITEM_REQUEST_URL, listener,null);
    String id="6";
    String isOpen="y";
    params = new HashMap<>();
    params.put("userID", userID);
    params.put("sessionID", sessionID);
    params.put("isOpen", isOpen);
    params.put("id", id);
}

@Override
public Map<String, String> getParams() {
    return params;
}

}

这是项目类

public class items extends BaseActivity {

private ProgressDialog pDialog;
private ArrayList<RowItem> rowItems = new ArrayList<RowItem>();
private ListView mylistview;
private CustomListAdapter adapter;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_items);

    pDialog = new ProgressDialog(this);
    pDialog.setMessage("Loading...");
    pDialog.show();

    Response.Listener<String> responseListener = new Response.Listener<String>() {
        @Override
        public void onResponse(String response) {
            try {
                JSONObject jsonResponse = new JSONObject(response);
                boolean error = jsonResponse.getBoolean("error");
                System.out.println(jsonResponse.toString());
                if (error){
                    String errorMessage = jsonResponse.getString("message");
                    AlertDialog.Builder builder = new AlertDialog.Builder(items.this);
                    builder.setMessage(errorMessage)
                            .setNegativeButton("Retry", null)
                            .create()
                            .show();
                }else {
                    JSONArray itemSet = jsonResponse.getJSONArray("itemSet");
                    for (int i = 0; i < itemSet.length(); i++){
                        JSONObject item = itemSet.getJSONObject(i);
                        String title = item.getString("title");
                        String seller = item.getString("nickName");
                        String price = item.getString("price");
                        String itemID = item.getString("itemID");
                        String Path;
                        JSONArray pic = item.getJSONArray("picPath");
                        if (pic.length()==0)
                        {
                            Path="uploads/default.jpg";
                        }else {
                             Path = pic.getString(0);
                        }
                        RowItem row=new RowItem(title,seller,price,Path,itemID);
                        rowItems.add(row);

                    }
                    mylistview = (ListView) findViewById(R.id.list);
                    CustomListAdapter adapter = new CustomListAdapter(items.this, rowItems);
                    System.out.println(rowItems.isEmpty());
                    mylistview.setAdapter(adapter);
                }
            }catch (JSONException e){
                e.printStackTrace();
            }
        }
    };
    Intent intent = getIntent();
    ArrayList<String> list =intent.getStringArrayListExtra("userInfo");
    System.out.println(list.toString());
    itemRequest itemRequest = new itemRequest(list.get(0),list.get(1),responseListener);
    RequestQueue queue = Volley.newRequestQueue(items.this);
    queue.add(itemRequest);

    pDialog.dismiss();
}

}

这是CustomListAdpater

public class CustomListAdapter extends BaseAdapter {
private Context context;
private List<RowItem> rowItems;
private LayoutInflater inflater = null;

public static final String IMAGE_BASEURL = "http://XXXXXXXXXXX/";

private LruCache<Integer, Bitmap> imageCache;
private RequestQueue queue;

public CustomListAdapter(Context context, List<RowItem> rowItems){
    this.context=context;
    this.rowItems=rowItems;
    inflater = LayoutInflater.from(context);

    final int maxMemory = (int) (Runtime.getRuntime().maxMemory() / 1024);
    final int cacheSize = maxMemory / 8;
    imageCache = new LruCache<>(cacheSize);

    queue = Volley.newRequestQueue(context);
}
@Override
public int getCount() {
    return rowItems.size();
}

@Override
public Object getItem(int position) {
    return rowItems.get(position);
}

@Override
public long getItemId(int position) {
    return rowItems.indexOf(getItem(position));
}

private class ViewHolder{
    ImageView imageView;
    TextView tv_title;
    TextView tv_seller;
    TextView tv_price;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {

    LayoutInflater mInflater = (LayoutInflater) context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);

    final RowItem row_pos = rowItems.get(position);
    final ViewHolder holder;
    System.out.print("=================================================================");
    if (convertView==null){
        convertView = mInflater.inflate(R.layout.custom_layout, null);
        holder = new ViewHolder();
        holder.tv_title = (TextView) convertView.findViewById(R.id.tv_title);
        holder.tv_seller = (TextView) convertView.findViewById(R.id.tv_seller);
        holder.tv_price = (TextView) convertView.findViewById(R.id.tv_price);

        convertView.setTag(holder);
    }else {
        holder = (ViewHolder) convertView.getTag();
    }
    holder.tv_title.setText(row_pos.getTv_title().toString());
    holder.tv_seller.setText(row_pos.getTv_seller().toString());
    holder.tv_price.setText(row_pos.getTv_price().toString());

    Bitmap bitmap = imageCache.get(Integer.parseInt(row_pos.getItemID()));
    holder.imageView = (ImageView) convertView.findViewById(R.id.image_view);

    if (bitmap != null){
        holder.imageView.setImageBitmap(bitmap);
        System.out.print("bitmap");
    }else {
        String imageURL = IMAGE_BASEURL + row_pos.getPath();
        ImageRequest request = new ImageRequest(imageURL, new Response.Listener<Bitmap>() {
            @Override
            public void onResponse(Bitmap response) {
                holder.imageView.setImageBitmap(response);
                imageCache.put(Integer.parseInt(row_pos.getItemID()), response);
                System.out.print(row_pos.getItemID()+"this is image");
            }
        }, 90, 90,
                Bitmap.Config.ARGB_8888,
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        Log.d("error", error.toString());
                    }
                });
        queue.add(request);
    }
    return convertView;
}

}

这是Rowitem类

public class RowItem {
private String tv_title;
private String tv_seller;
private String tv_price;
private String image_view;
private Bitmap bitmap;
private String Path;
private String itemID;

public RowItem(String tv_title, String tv_seller, String tv_price, String image_view, String itemID){
    this.tv_title = tv_title;
    this.tv_seller = tv_seller;
    this.tv_price = tv_price;
    this.image_view = image_view;
    this.Path =  image_view;
    this.itemID = itemID;
}

public String getTv_title() {
    return tv_title;
}
public void setTv_title(String tv_title) {
    this.tv_title = tv_title;
}

public String getTv_seller() {
    return tv_seller;
}
public void setTv_seller(String tv_seller) {
    this.tv_seller = tv_seller;
}

public String getTv_price() {
    return tv_price;
}
public void setTv_price(String tv_price) {
    this.tv_price = tv_price;
}

public String getImage_view() {
    return image_view;
}
public void setImage_view(String image_view) {
    this.image_view = image_view;
}

public Bitmap getBitmap(){
    return bitmap;
}
public void setBitmap(Bitmap bitmap){
    this.bitmap = bitmap;
}

public String getPath(){
    return Path;
}
public void setPath(String Path){
    this.Path = Path;
}

public String getItemID(){
    return itemID;
}
public void setItemID(){
    this.itemID = itemID;
}

}

只有图像无法显示其他图像正常。