如何将pdf缩略图设置为自定义适配器列表视图的图像视图？

Question

我的代码大部分工作正常。我不知道如何将文件预览位图图像传递给构造函数。如何将位图图像设置为自定义ListView适配器的图像视图？

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

    fileNameList=(ArrayList<File_Explorer>)getLastNonConfigurationInstance();

    if(fileNameList==null) {

        ListView lv = (ListView)findViewById(R.id.listView);
        lv.setItemsCanFocus(false);
        lv.setChoiceMode(lv.CHOICE_MODE_MULTIPLE);
        fileNameList = new ArrayList<File_Explorer>();
        arrayAdapter = new ArrayAdapter<File_Explorer>(this,
                android.R.layout.simple_list_item_1, fileNameList);

        lv.setAdapter(arrayAdapter);

        File file =new File(Environment.getExternalStorageDirectory().getAbsolutePath(),"Every_Day");
        list = file.listFiles();
        byte[] bytes;
        try {
            FileInputStream is = new FileInputStream(file);

            // Get the size of the file
            long length = file.length();
            bytes = new byte[(int) length];
            int offset = 0;
            int numRead = 0;
            while (offset < bytes.length && (numRead=is.read(bytes, offset, bytes.length-offset)) >= 0) {
                offset += numRead;
            }
            ByteBuffer buffer = ByteBuffer.NEW(bytes);
            String data = Base64.encodeToString(bytes, Base64.DEFAULT);
            PDFFile pdf_file = new PDFFile(buffer);
            PDFPage page = pdf_file.getPage(2, true);

            RectF rect = new RectF(0, 0, (int) page.getBBox().width(),
                    (int) page.getBBox().height());

            Bitmap image = page.getImage((int)rect.width(), (int)rect.height(), rect);
            FileOutputStream os = new FileOutputStream("/storage/extSdCard/pdf.jpg");
            image.compress(Bitmap.CompressFormat.PNG, 80, os);
             ImageView i = ((ImageView) findViewById(R.id.fileimage));
            BitmapDrawable ob = new BitmapDrawable(getResources(), image);
            i.setBackgroundDrawable(ob);

            if(list!=null) {
                for (int i = 0; i < list.length; i++) {
                    // *** problem below -- how to pass the image to File_Explorer? 
                    fileNameList.add(new File_Explorer(list[i].getName(),???));

                }
            }

        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        arrayList = new ArrayList<File_Explorer>();
        arrayList.addAll(fileNameList);
        arrayAdapter = new FileExplorerArrayAdapter(this,arrayList);
        lv.setAdapter(arrayAdapter);
        lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                String file = list[(int)id].getName();
                openPdfIntent(file);
            }
        });
    }
}
}