Question

I need to implement progress bar in an android project when an intent is passed through one activity another, and some a fair bit of data from the internet is being downloaded in second activity and as such there is a noticeable delay between when the user clicks on an item and when the Activity displays.

I’ve tried a few different approaches for this but nothing seems to work as desired. I am using the following code for it. And the progress dialog is going inside infinite loop.

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

          int myProgress;

          @Override

          protected void onPostExecute(Bitmap result) {
              iv.setVisibility(View.VISIBLE);
              iv.setImageBitmap(result);
              dialog.cancel();
              dialog.dismiss();
          }

          @Override
          protected void onPreExecute() {
            dialog = ProgressDialog.show(ProfileNormalUserPhotos.this, "Loading...", "Please wait...");

          }

          @Override
          protected Bitmap doInBackground(String...paths) {
             return DownloadFile(imageUrl);

         }
          @Override
          protected void onProgressUpdate(Integer... values) {
           // TODO Auto-generated method stub
           progressBar.setProgress(values[0]);
          }

         }

    public Bitmap DownloadFile(String url){
        URL myFileUrl;
         Bitmap bitmap=null;
        try {

            myFileUrl = new URL(imageUrl);
         HttpURLConnection conn= (HttpURLConnection)myFileUrl.openConnection();
         conn.setDoInput(true);
         conn.setConnectTimeout(10000);
         conn.setReadTimeout(10000);
         conn.connect();
         InputStream is = conn.getInputStream();
         bmImg = BitmapFactory.decodeStream(is);
         bitmap = BitmapFactory.decodeStream((InputStream) new URL(  
         imageUrl).getContent()); 
        bitmap = Bitmap.createScaledBitmap(bitmap,70 , 70, true);
        System.out.println("name of bitmap"+bitmap.toString());

        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            System.out.println(e);
        }
        return bitmap;

    }

And following is my adapter class

             public class ImageAdapter extends BaseAdapter {  
                Context mContext;
    private String[] stringOnTextView;

     public ImageAdapter(Context c) {  
      mContext = c;  
     }  
    // BitmapManager.INSTANCE. setPlaceholder(BitmapFactory.decodeResource(  
     //           context.getResources(), R.drawable.icon));  


    public ImageAdapter(Context Context,
            String[] stringOnTextView) {
        this.mContext=Context;
        this.stringOnTextView=stringOnTextView;
    }

    public int getCount() {  
      return stringOnTextView.length;  
     }  


    public Object getItem(int position) {  
      return null;  
     }  

     public long getItemId(int position) {  
      return position;  
     }  


     public View getView(int position, View convertView, ViewGroup parent) {

        System.out.println("**************"+position);

         View v = null;
        if(convertView==null){


            try{

            {
                  System.gc();
                // dialog = ProgressDialog.show(ProfileNormalUserPhotos.this, "Loading...", "Please wait...");
                  imageUrl = "http://ondamove.it/English/images/users/";
                  imageUrl=imageUrl+stringOnTextView[position];
                  System.out.println(imageUrl);

                  LayoutInflater li = getLayoutInflater();
                  v = li.inflate(R.layout.icon, null);
                  TextView tv = (TextView)v.findViewById(R.id.text);
                  tv.setText("Profile Image "+(position+1));
                  /* URL myFileUrl = new URL(imageUrl);
                   HttpURLConnection conn= (HttpURLConnection)myFileUrl.openConnection();
                   conn.setDoInput(true);
                   conn.setConnectTimeout(10000);
                   conn.setReadTimeout(10000);
                   conn.connect();
                   InputStream is = conn.getInputStream();

                   bmImg = BitmapFactory.decodeStream(is);
                   Bitmap bitmap = BitmapFactory.decodeStream((InputStream) new URL(  
                         imageUrl).getContent()); 

                    bitmap = Bitmap.createScaledBitmap(bitmap, 80, 80, true);*/

                    // new ImageView(mContext);
                   iv= (ImageView)v.findViewById(R.id.image);
                    new BackgroundAsyncTask().execute(imageUrl);
                    //iv.setImageBitmap(bitmap);
                    //dialog.cancel();

                    // System.out.println(bitmap.getHeight());

                     System.out.println("++++++++"+R.id.image);


                   }
           }catch (Exception e) {
            e.printStackTrace();
            System.out.println(e);
        }
        }
        else
        {
            try{
            v = convertView;}
            catch(Exception e){
                System.out.println(e);
            }
        }
        return v;
    }
}

Can anyone help me over this?

Answer 1

Try AsyncTask,

 private class myAsyncTask extends AsyncTask<String, Void, Void>
    {
        ProgressDialog mProgressDialog;
        @Override
        protected void onPreExecute() {
            mProgressDialog = ProgressDialog.show(Activity_name.this, "Loading...", "Please wait...");
        }
        @Override
        protected Void doInBackground(String... params) {

                    String url = params[0];
            //  you can do download from internet here
            return null;
        }
        @Override
        protected void onPostExecute(Void result) {
            mProgressDialog.dismiss();
        }
    }