How to download file/image from url to your android app

Question

I need my android app to make request to url to download an image from this url so I have built this class to help me, BUT it didn\'t work ???

public class M         


        

Answer 1

The problem with your code is you have not read the InputStream. You should try this

Bitmap bitmap = BitmapFactory.decodeStream(is); 
return bitmap;

and make the Asynctask return type as Bitmap. Or, As you have used that is in postExecute() your doInBackground() should return that InputStream object is. But you are returning void.

Okey.Try this edited Asynctask.

    private  class MyAsnyc extends  AsyncTask  {
    File file;
    @Override 
    protected File doInBackground( Void... params ) { 
        InputStream is = null;
        File path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
        file = new File( path , "Demo Picture.jpg" ) ;  
        try { // Make sure the Pictures directory exists.path.mkdirs() ; URL url = new URL ( "http: / /androidsaveitem .appspot.com/download.jpg") ; URLConnection ucon = url.openConnection ( ) ; 
            path.mkdirs();

            OutputStream os = new FileOutputStream(file) ; 
            byte [ ] data = new byte [ is.available ( ) ] ;
            is.read ( data ) ; os.write (data );is.close ( ) ; os.close ( ) ; 
            return file;
        }
        catch (Exception e){ 
            Log .d ( "ImageManager " , " Error: " + e ) ;
        }           

        return null;
    }
    protected void onPostExecute (File file) {
        try{
            MediaScannerConnection.scanFile( null , new String [] {file.toString( ) } , null , new MediaScannerConnection.OnScanCompletedListener ( ) { public void onScanCompleted (String path, Uri uri) { 
                Log.i ( " External Storage" , " Scanned " + path + " : " ) ; Log.i ( " E x t e r n a l S t o r a g e " , " - > u r i = " + uri ) ; } } ) ;
        }catch (Exception e) {
            // TODO: handle exception
        }
    }}