将图像作为ArrayList传递 <Bitmap> 从片段到自定义列表适配器

Question

我无法将位图数据从片段类发送到自定义适配器类。 日志显示以下错误。

FATAL EXCEPTION: main
Process: com.example.readersden, PID: 21025 
java.lang.IndexOutOfBoundsException: Invalid index 0, size is 0
atjava.util.ArrayList.throwIndexOutOfBoundsException(ArrayList.java:255)
at java.util.ArrayList.get(ArrayList.java:308)
at com.example.readersden.CardAdapter.getView(CardAdapter.java:82)

片段类（在AsyncTask的onPostExecute方法内部）：

            Bitmap.Config conf = Bitmap.Config.ARGB_8888; 

            Bitmap bmp = Bitmap.createBitmap(w, h, conf);
            try {
                JSONObject imageInfo = volumeObject.getJSONObject("imageLinks");
                new GetBookThumb().execute(imageInfo.getString("thumbnail"));
            } catch (JSONException je) {
                bookThumb.add(0, bmp);
                je.printStackTrace();
            }

获取图像类（在AsyncTask类的doInBackground方法内部）：

            InputStream thumbIn = thumbConn.getInputStream();
            BufferedInputStream thumbBuff = new BufferedInputStream(thumbIn);
            thumbImg = BitmapFactory.decodeStream(thumbBuff);
            bookThumb.add(0, thumbImg);
            thumbBuff.close();
            thumbIn.close();

自定义适配器类（在getView方法内部）：

            ArrayList<Bitmap> bookThumb;
            e.thumb.setImageBitmap(bookThumb.get(pos));

我是android开发的新手，它非常有趣！ ^。^谢谢！

编辑：

public CardAdapter(ArrayList<String> bookTitle,
        ArrayList<String> bookAuthor, ArrayList<String> bookPublishDate,
        ArrayList<String> bookPages, ArrayList<Bitmap> bookThumb,
        Activity mAct) {
        super();
        this.bookTitle = bookTitle;
        this.bookAuthor = bookAuthor;
        this.bookPublishDate = bookPublishDate;
        this.bookPages = bookPages;
        this.bookThumb = bookThumb;
        this.mAct = mAct;

        mInflater = (LayoutInflater) mAct
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }


    @Override
    public View getView(int pos, View view, ViewGroup viewGroup) {


        LayoutField e;
            if (view == null) {
            view = mInflater.inflate(R.layout.layout_card, viewGroup, false);
            e = new LayoutField();
            e.title = (TextView) view.findViewById(R.id.book_title);
            e.thumb = (ImageView) view.findViewById(R.id.book_thumbnail);
            e.author = (TextView) view.findViewById(R.id.book_author);
            e.publishDate = (TextView) view
                .findViewById(R.id.book_publish_date);
            e.pages = (TextView) view.findViewById(R.id.book_pages);
            view.setTag(e);
        } else
            e = (LayoutField) view.getTag();

        e.title.setText(bookTitle.get(pos));
        e.thumb.setImageBitmap(bookThumb.get(pos));
        e.author.setText(bookAuthor.get(pos));
        e.publishDate.setText(bookPublishDate.get(pos));
        e.pages.setText(bookPages.get(pos));

        return view;
    }

    class LayoutField {
        TextView title, author, publishDate, pages;
        ImageView thumb;
    }
}

传递文字效果很好！ 仅图像给出了超出范围的索引。

Answer 1

我在错误的地方调用了notifydatasetchanged（），即在将图像下载到后台线程之前。 由于我的getCount（）返回了图像数..到我调用notifydatasetchanged（）时，尚未填充ArrayList（即，后台线程未完成）。 希望它能在某个时候帮助出现类似错误的人。 谢谢大家的帮助！