android - 从服务器下载图像时如何在android中显示图像

Question

可能重复：
图像未显示在图像视图上

如何在从服务器下载图像时在 android 中显示图像 请任何人都可以与我分享有关此的代码

Answer 1

Drawable drawable = LoadImage(ImageURL);
PhotoImageView.setImageDrawable(drawable);    
//PhotoImageView is the ImageView in which you want to load your image from server

public Drawable LoadImage(String url)
{
    try
    {
        InputStream is = (InputStream) new URL(url).getContent();
        Drawable d = Drawable.createFromStream(is, "src name");
        return d;
    }
    catch (Exception e)
    {
        System.out.println("Exc=" + e);
        return null;
    }
}

Answer 2

请使用以下代码从 url 获取图像并显示到 imageview 中。

public class image extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        Bitmap bitmap = DownloadImage("http://www.gophoto.it/view.php?i=http://1.bp.blogspot.com/-2LTvCCufBKc/T3L3KgcTj2I/AAAAAAAABbQ/Ki60e1LU9sE/s1600/Sachin%2BTendulkar.png");

        RelativeLayout mRlayout1 = (RelativeLayout) findViewById(R.id.mRlayout1);
        Drawable d=new BitmapDrawable(bitmap);
        mRlayoutLogin.setBackgroundDrawable(d);
    }

    private InputStream OpenHttpConnection(String urlString) throws IOException {
        InputStream in = null;
        int response = -1;

        URL url = new URL(urlString);
        URLConnection conn = url.openConnection();

        if (!(conn instanceof HttpURLConnection))
            throw new IOException("Not an HTTP connection");

        try {
            HttpURLConnection httpConn = (HttpURLConnection) conn;
            httpConn.setAllowUserInteraction(false);
            httpConn.setInstanceFollowRedirects(true);
            httpConn.setRequestMethod("GET");
            httpConn.connect();
            response = httpConn.getResponseCode();
            if (response == HttpURLConnection.HTTP_OK) {
                in = httpConn.getInputStream();
            }
        } catch (Exception ex) {
            throw new IOException("Error connecting");
        }
        return in;
    }

    private Bitmap DownloadImage(String URL) {
        Bitmap bitmap = null;
        InputStream in = null;
        try {
            in = OpenHttpConnection(URL);
            bitmap = BitmapFactory.decodeStream(in);
            in.close();
        } catch (IOException e1) {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }
        return bitmap;
    }
}

Answer 3

通常，您在使用 AsycTask 下载时会显示旋转的 ProgressBar：

public class Downloader extends AsyncTask<String,Integer,Bitmap> {

    @Override
    protected void onPreExecute() {
        // show spinning progress bar
    }

    @Override
    protected Bitmap doInBackground(String... arg0) {
        // download the image
        return null;
    }

    @Override
    protected void onPostExecute(Bitmap downloadedImage) {
        // hide spinning progress bar
        // show downloaded image
    }

}

Answer 4

试试这个可能对你有帮助。

class DownloadImage extends AsyncTask<Void, Void, Void> {

    private ProgressDialog bar;

    @Override
    protected void onPostExecute(Void result) {
        super.onPostExecute(result);
        bar.dismiss();
    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        bar =  new ProgressDialog(context);
        bar.setIndeterminate(true);
        bar.setTitle(context.getString(R.string.app_name));
        bar.setMessage(context.getString(R.string.please_wait));
        bar.show();
    }

    @Override
    protected Void doInBackground(Void... arg0) {
        downloadImage();
        return null;
    }

    void downloadImage() {
        //Put the logic for download image from url
    }
}

或请在此处查看。