title: Opening PDF from external URL says "Open File: No apps can perform this action"
body: <p>I am trying to open PDF files from external URL. The code is the next:</p>
  
  <pre><code>private void cargaPdf(Uri url){
      //File file = new File(Environment.getExternalStorageDirectory().getAbsolutePath() +"/"+ filename);
      Intent target = new Intent(Intent.ACTION_VIEW);
      target.setDataAndType(url,"application/pdf");
      target.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
  
      Intent intent = Intent.createChooser(target, "Open File");
      try {
          startActivity(intent);
      } catch (ActivityNotFoundException e) {
          // Instruct the user to install a PDF reader here, or something
      }
  }
  </code></pre>
  
  <p>I have installed adobe and google PDF viewer but when i push the buttom that calls "cargaPdf(Uri url)" function with this url(as you can see is a pdf file):</p>
  
  <pre><code>Uri.parse(https://dl.dropboxusercontent.com/s/oulzgpgnq2ca1ly/KorfbalSpa.pdf?dl=0);
  </code></pre>
  
  <p>It appears in the screen in spanish "Open File Ninguna aplicacion puede realizar esta accion" or english "Open file No apps can perform this action". What happen?</p>
  
  <p><strong>Edit 1:</strong> Ok, now i know that i have to download the file to see it, so, i did this code in the activity:</p>
  
  <pre><code>public void cargaDescripcion(View view){
      Log.d("CargaDescripcion", "Antes del directorio");
      String extStorageDirectory = Environment.getExternalStorageDirectory()
              .toString();
      File folder = new File(extStorageDirectory, "Mypdf");
      folder.mkdir();
      File file = new File(folder, "Read.pdf");
      try {
          file.createNewFile();
          Log.d("CargaDescripcion", "File creado");
      } catch (IOException e1) {
          e1.printStackTrace();
      }
      Downloader.DownloadFile(deporte.getUrlDescEs(), file);
      Log.d("CargaDescripcion", "Despues de descargarlo");
      showPdf();
      //folder.delete();
  }
  
  public void showPdf()
  {
      Log.d("showPdf", "Entramos en show pdf");
      File file = new File(Environment.getExternalStorageDirectory()+"/Mypdf/Read.pdf");
      PackageManager packageManager = getPackageManager();
      Intent testIntent = new Intent(Intent.ACTION_VIEW);
      testIntent.setType("application/pdf");
      List list = packageManager.queryIntentActivities(testIntent, PackageManager.MATCH_DEFAULT_ONLY);
      Intent intent = new Intent();
      intent.setAction(Intent.ACTION_VIEW);
      Uri uri = Uri.fromFile(file);
      intent.setDataAndType(uri, "application/pdf");
      startActivity(intent);
      //file.delete();
  }
  </code></pre>
  
  <p>And this class for download the pdf:</p>
  
  <pre><code>public class Downloader {
  public static void DownloadFile(String fileURL, File directory) {
      try {
          FileOutputStream f = new FileOutputStream(directory);
          URL u = new URL(fileURL);
          HttpURLConnection c = (HttpURLConnection) u.openConnection();
          c.setRequestMethod("GET");
          c.setDoOutput(true);
          c.connect();
          InputStream in = c.getInputStream();
          byte[] buffer = new byte[1024];
          int len1 = 0;
          while ((len1 = in.read(buffer)) &gt; 0) {
              f.write(buffer, 0, len1);
          }
          f.close();
      } catch (Exception e) {
          e.printStackTrace();
      }
  }
  </code></pre>
  
  <p>}</p>
  
  <p>I got it from here <a href="https://stackoverflow.com/questions/20603713/opening-pdf-file-from-server-using-android-intent">Opening pdf file from server using android intent</a></p>
  
  <p>Edit 2: Now this is the code which download and shows the file:</p>
  
  <pre><code>public void cargaDescripcion(View view){
      download(deporte.getUrlDescEs());
      showPdf();
      //folder.delete();
  }
  
  public void download(String url)
  {
      new DownloadFile().execute(url, "read.pdf");
  }
  
  public void showPdf()
  {
      File pdfFile = new File(Environment.getExternalStorageDirectory() + "/Mypdf/" + "read.pdf");  // -&gt; filename = maven.pdf
      Uri path = Uri.fromFile(pdfFile);
      Intent pdfIntent = new Intent(Intent.ACTION_VIEW);
      pdfIntent.setDataAndType(path, "application/pdf");
      pdfIntent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
  
      try{
          startActivity(pdfIntent);
      }catch(ActivityNotFoundException e){
          Toast.makeText(SelectedSportActivity.this, "No Application available to view PDF", Toast.LENGTH_SHORT).show();
      }
  }
  private class DownloadFile extends AsyncTask&lt;String, Void, Void&gt; {
  
      @Override
      protected Void doInBackground(String... strings) {
          String fileUrl = strings[0];   // -&gt; url del archivo
          String fileName = strings[1];  // -&gt; nombre del archivo.pdf
          String extStorageDirectory = Environment.getExternalStorageDirectory().toString();
          File folder = new File(extStorageDirectory, "Mypdf");
          folder.mkdir();
  
          File pdfFile = new File(folder, fileName);
  
          try{
              pdfFile.createNewFile();
          }catch (IOException e){
              e.printStackTrace();
          }
          Downloader.downloadFile(fileUrl, pdfFile);
          return null;
      }
  }
  </code></pre>
  
  <p>However, the file system is not created by app and file is not downloaded before the app arrives to the next point, that it is "show". So, the file does not exists when the app looks for it.</p>
  
  <p>Edit 3: to SOLVE the show problem i used onPostExecute of asynctask method:</p>
  
  <pre><code>@Override
      protected void onPostExecute(Void aVoid) {
          super.onPostExecute(aVoid);
          showPdf();
      }
  </code></pre>