Question

我总是在调用此方法时得到响应NULL但是如果假设我在浏览器中运行它会显示图像.public Bitmap getBitmapFromURL（String src）{ 位图bmImg; URL myFileUrl = null;

    try {
        myFileUrl = new URL("http://www.russiawear.com/components/com_virtuemart/shop_image/product/youth_russia_usa_4e2f7f78b543c.jpg");

        HttpURLConnection conn = (HttpURLConnection) myFileUrl
                .openConnection();
        conn.setDoInput(true);
        conn.connect();
        InputStream is = conn.getInputStream();

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

        bmImg = BitmapFactory.decodeStream(is, null, options);
        return bmImg;
    } catch (Exception e) {
        e.printStackTrace();
        return null;
    }
}`

什么可能有问题？

Answer 1

我只是使用它，在我的情况下它的工作正常。

URL newurl;
try
{
newurl = new URL("http://www.russiawear.com/components/com_virtuemart/shop_image/product/youth_russia_usa_4e2f7f78b543c.jpg");  
bitmap = BitmapFactory.decodeStream(newurl.openConnection().getInputStream());
}
catch (IOException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}

<强>更新

来自网址的下载文件代码，

    try
    {
        URL url = new URL("http://www.russiawear.com/components/com_virtuemart/shop_image/product/youth_russia_usa_4e2f7f78b543c.jpg"); //you can write here any link
        File file = new File("/sdcard/temp.jpg");
        /* Open a connection to that URL. */
        URLConnection ucon = url.openConnection();

        /*
         * Define InputStreams to read from the URLConnection.
         */
        InputStream is = ucon.getInputStream();
        BufferedInputStream bis = new BufferedInputStream(is);
        /*
         * Read bytes to the Buffer until there is nothing more to read(-1).
         */
        ByteArrayBuffer baf = new ByteArrayBuffer(50);
        int current = 0;
        while ((current = bis.read()) != -1)
        {
            baf.append((byte) current);
        }

        /* Convert the Bytes read to a String. */
        FileOutputStream fos = new FileOutputStream(file);
        fos.write(baf.toByteArray());
        fos.close();
    }
    catch (IOException e)
    {
        Log.d("ImageManager", "Error: " + e);
    }

然后使用文件

创建位图

bitmap = BitmapFactory.decodeFile("/sdcard/temp.jpg");

Answer 2

private Bitmap loadBitmap() {
    Bitmap bmQR = null;
    InputStream inputStream = null;

    try {
        inputStream = OpenHttpConnection(url);
        bmQR = BitmapFactory.decodeStream(inputStream);
        inputStream.close();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    return bmQR;
}

private InputStream OpenHttpConnection(String strURL) throws IOException {
    InputStream is = null;
    URL url = new URL(strURL);
    URLConnection urlConnection = url.openConnection();

    try {
        HttpURLConnection httpConn = (HttpURLConnection) urlConnection;
        httpConn.setRequestMethod("GET");
        httpConn.connect();

        if (httpConn.getResponseCode() == HttpURLConnection.HTTP_OK) {
            is = httpConn.getInputStream();
        }
    } catch (Exception ex) {
    }
    return is;
}

无法在Android中下载图像

2 个答案: