Android Network Download pictures

1  Packagenet.learn2develop.Networking;2 3 Importandroid.app.Activity;4 ImportAndroid.os.Bundle;5 6 Importjava.io.IOException;7 ImportJava.io.InputStream;8 9 Importjava.net.HttpURLConnection;Ten ImportJava.net.URL; One Importjava.net.URLConnection; A ImportAndroid.util.Log; -  - ImportAndroid.widget.ImageView; the ImportAndroid.widget.Toast; - ImportAndroid.graphics.Bitmap; - Importandroid.graphics.BitmapFactory; - ImportAndroid.os.AsyncTask; +  Public classNetworkingactivityextendsActivity { -          + ImageView img;  A      at     PrivateInputStream openhttpconnection (String urlstring)throwsIOException -     { -InputStream in =NULL; -         intResponse =-1; -                 -URL url =NewURL (urlstring); inURLConnection conn =url.openconnection (); -                   to         if(! (Conninstanceofhttpurlconnection))  +             Throw NewIOException ("Not an HTTP connection");  -         Try{ theHttpURLConnection Httpconn =(httpurlconnection) conn; *Httpconn.setallowuserinteraction (false); $Httpconn.setinstancefollowredirects (true);Panax NotoginsengHttpconn.setrequestmethod ("GET"); - Httpconn.connect (); theResponse =Httpconn.getresponsecode ();  +             if(Response = =HTTPURLCONNECTION.HTTP_OK) { Ain =Httpconn.getinputstream ();  the             }                      +         } -         Catch(Exception ex) $         { $LOG.D ("Networking", Ex.getlocalizedmessage ()); -             Throw NewIOException ("Error connecting"); -         } the         returnIn ;  -     }Wuyi      the     PrivateBitmap downloadimage (String URL) -     {         WuBitmap Bitmap =NULL; -InputStream in =NULL;  About         Try { $in =openhttpconnection (URL); -Bitmap =Bitmapfactory.decodestream (in); - in.close (); -}Catch(IOException E1) { ALOG.D ("Networkingactivity", E1.getlocalizedmessage ());  +         } the         returnbitmap;  -     } $          the  the     Private classDownloadimagetaskextendsAsynctask<string, Void, bitmap> { the         protectedBitmap doinbackground (String ... urls) { the             returnDownloadimage (urls[0]); -         } in          the         protected voidOnPostExecute (Bitmap result) { theImageView img =(ImageView) Findviewbyid (r.id.img); About Img.setimagebitmap (result); the         } the     } the  + @Override -      Public voidonCreate (Bundle savedinstancestate) { the         Super. OnCreate (savedinstancestate);Bayi Setcontentview (r.layout.main); the          the         NewDownloadimagetask (). Execute ("Http://www.mayoff.com/5-01cablecarDCP01934.jpg"); - } -}

Because the Downloadimage () method is synchronous-this means that no control is returned until the picture is downloaded-so calling it directly causes the active UI to freeze, using Asynctask to allow background tasks to be performed in a separate thread, and then returning the results in the UI thread.

Android Network Download pictures