Question

我正在动态创建Imageview并显示它。但是我在滚动时遇到了重载问题所以我决定使用NetworkImageView但是在这里我无法设置位图。它没有显示任何错误，但它没有显示任何图像。在我的代码下面......

final NetworkImageView imageView = new NetworkImageView(context);
    LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(150,
            200);
    params.weight = 1;
    //imageView.setImageBitmap(null);
    imageView.setLayoutParams(params);
    imageView.setMaxHeight(200);
    imageView.setMaxWidth(150);
    // bitmap =//
    // BitmapFactory.decodeResource(context.getResources(),R.drawable.ic_menu_folder);
    // Log.i("Bitmaps Counts", String.valueOf(pos));
    /*    comment all this...
    new Thread() {
        public void run() {


                bitmap = downloadImage(tempValues.getItemAbsolutePath());


            ((Activity) context).runOnUiThread(new Runnable() {
                @Override
                public void run() {

                    imageView.setImageBitmap(bitmap);

                }
            });

        }
    }.start();*/
    RequestQueue requestQueue = Volley.newRequestQueue(getApplicationContext());
    ImageLoader mImageLoader = new ImageLoader(requestQueue,new LruBitmapCache(1000000));
     mImageLoader.get(tempValues.getItemAbsolutePath(),
            ImageLoader.getImageListener(imageView,
                   R.android.defaultimg,
                   R.android.errorimg));

    layout.addView(imageView);

downloadImage code ..

/* unused method
      private Bitmap downloadImage(String url) {
        Bitmap bitmap = null;
        InputStream stream = null;
        BitmapFactory.Options bmOptions = new BitmapFactory.Options();
        bmOptions.inSampleSize = 1;

        try {
            stream = getHttpConnection(url);
            bitmap = BitmapFactory.decodeStream(stream, null, bmOptions);
            stream.close();

        } catch (IOException e1) {
            e1.printStackTrace();
        }
        return bitmap;
    }

    private InputStream getHttpConnection(String urlString) throws IOException {
        InputStream stream = null;
        URL url = new URL(urlString);
        URLConnection connection = url.openConnection();

        try {
            HttpURLConnection httpConnection = (HttpURLConnection) connection;
            httpConnection.setRequestMethod("GET");
            httpConnection.connect();

            if (httpConnection.getResponseCode() == HttpURLConnection.HTTP_OK) {
                stream = httpConnection.getInputStream();
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        }
        return stream;
    }*/

错误日志

05-12 19：11：13.971：E / AndroidRuntime（11177）：致命异常：Thread-7325 05-12 19：11：13.971：E / AndroidRuntime（11177）：进程：com.dar.app，PID：11177 05-12 19：11：13.971：E / AndroidRuntime（11177）：java.lang.NegativeArraySizeException：-350 05-12 19：11：13.971：E / AndroidRuntime（11177）：at com.android.volley.toolbox.DiskBasedCache.streamToBytes（DiskBasedCache.java:316） 05-12 19：11：13.971：E / AndroidRuntime（11177）：at com.android.volley.toolbox.DiskBasedCache.get（DiskBasedCache.java:117） 05-12 19：11：13.971：E / AndroidRuntime（11177）：at com.android.volley.CacheDispatcher.run（CacheDispatcher.java:100）

Answer 1

最终代码

public class DownloadImageTask extends AsyncTask<String, Void, Bitmap> {
    private ImageView imageView;
    private Bitmap image;
    private LinearLayout linear;

    public DownloadImageTask(ImageView imageView, LinearLayout linear) {
       this.imageView = imageView;
       this.linear = linear;
    }

    protected Bitmap doInBackground(String... urls) {
        String urldisplay = urls[0];
        try {
            InputStream in = new java.net.URL(urldisplay).openStream();
            image = BitmapFactory.decodeStream(in);
        } catch (Exception e) {
            image = null;
        }
        return image;
    }

    @SuppressLint("NewApi")
    protected void onPostExecute(Bitmap result) {
        if (result != null) {
            imageView.setImageBitmap(result);
            linear.addView(imageView);
        }
    }
}

现在请致电您的代码：

final ImageView imageView = new ImageView(context);
final LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(150, 200);
params.weight = 1;
imageView.setLayoutParams(params);
imageView.setMaxHeight(200);
imageView.setMaxWidth(150);

new DownloadImageTask(imageView, layout).execute(tempValues.getItemAbsolutePath());

Answer 2

你可以使用凌空图像下载

很容易默认img设置...图像的加载器请求.. 如果图像使用url找到它将设置..或如果错误它将设置错误图像..这样你将告知有关加载img的错误

 RequestQueue requestQueue = Volley.newRequestQueue(getApplicationContext());
 ImageLoader mImageLoader = new ImageLoader(requestQueue,new LruBitmapCache(1000000));
 mImageLoader.get(<img-url>,
                ImageLoader.getImageListener(<imageview-object>,
                       R.drawable.defaultimg,
                       R.drawable.errorimg));

将位图设置为NetworkImageView

2 个答案: