Question

我使用了所有标准网络相关代码来获取约45KB to 75KB的图像，但所有这些代码都失败了这些方法适用于大约3-5KB图像大小的文件。如何实现45 - 75KB的下载图像，以便在我的网络操作中在Android上的ImageView上显示它我已经使用过的东西

final URL url = new URL(urlString);

final URLConnection conn = url.openConnection();
HttpURLConnection httpConn = (HttpURLConnection) conn;

httpConn.setAllowUserInteraction(true);

httpConn.setInstanceFollowRedirects(true);

httpConn.setRequestMethod("GET");

httpConn.connect();

和我使用的第二个选项是::

DefaultHttpClient httpClient = new DefaultHttpClient();

HttpGet getRequest = new HttpGet(urlString);

HttpResponse response = httpClient.execute(getRequest);

为什么此代码适用于较小尺寸图像而不适用于较大尺寸图像。？

Answer 1

您下载的图片大小非常无关紧要。它使用BitmapFactory.decodeStream解码的大小是您处理图像所需的内存。因此，重新采样可能很有用。

    Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;

    BitmapFactory.decodeStream(is, null, options);

    Boolean scaleByHeight = Math.abs(options.outHeight - TARGET_HEIGHT) >= Math.abs(options.outWidth - TARGET_WIDTH);

    if(options.outHeight * options.outWidth >= 200*200){
    // Load, scaling to smallest power of 2 if dimensions >= desired dimensions
    double sampleSize = scaleByHeight
            ? options.outHeight / TARGET_HEIGHT
            : options.outWidth / TARGET_WIDTH;
    options.inSampleSize = 
          (int)Math.pow(2d, Math.floor(
          Math.log(sampleSize)/Math.log(2d)));
    }

    // Do the actual decoding
    options.inJustDecodeBounds = false;

    is.close();
    is = getHTTPConnectionInputStream(sUrl);
    Bitmap img = BitmapFactory.decodeStream(is, null, options);
    is.close();

Answer 2

很高兴看到您使用哪种代码将响应解码为位图。无论如何，尝试使用像这样的BufferedInputStream：

public Bitmap getRemoteImage(final URL aURL) { 
  try { 
    final URLConnection conn = aURL.openConnection(); 
    conn.connect(); 
    final BufferedInputStream bis = new BufferedInputStream(conn.getInputStream()); 
    final Bitmap bm = BitmapFactory.decodeStream(bis); 
    return bm; 
  } catch (IOException e) { 
    Log.d("DEBUGTAG", "Oh noooz an error..."); 
  } 
  return null; 
}

适用于较大图像的Android Image Getter

2 个答案: