android Pobierz pdf z adresu url, a następnie otwórz go za pomocą czytnika pdf

Jest to najlepsza metoda pobierania i przeglądania plików PDF.Możesz po prostu nazwać go z dowolnego miejsca jak

PDFTools.showPDFUrl(context, url);

Tutaj wpisz kod. To będzie działać dobrze

public class PDFTools {
private static final String TAG = "PDFTools";
private static final String GOOGLE_DRIVE_PDF_READER_PREFIX = "http://drive.google.com/viewer?url=";
private static final String PDF_MIME_TYPE = "application/pdf";
private static final String HTML_MIME_TYPE = "text/html";


public static void showPDFUrl(final Context context, final String pdfUrl ) {
    if ( isPDFSupported( context ) ) {
        downloadAndOpenPDF(context, pdfUrl);
    } else {
        askToOpenPDFThroughGoogleDrive( context, pdfUrl );
    }
}


@TargetApi(Build.VERSION_CODES.GINGERBREAD)
public static void downloadAndOpenPDF(final Context context, final String pdfUrl) {
    // Get filename
    //final String filename = pdfUrl.substring( pdfUrl.lastIndexOf( "/" ) + 1 );
    String filename = "";
    try {
        filename = new GetFileInfo().execute(pdfUrl).get();
    } catch (InterruptedException e) {
        e.printStackTrace();
    } catch (ExecutionException e) {
        e.printStackTrace();
    }
    // The place where the downloaded PDF file will be put
    final File tempFile = new File( context.getExternalFilesDir( Environment.DIRECTORY_DOWNLOADS ), filename );
    Log.e(TAG,"File Path:"+tempFile);
    if ( tempFile.exists() ) {
        // If we have downloaded the file before, just go ahead and show it.
        openPDF( context, Uri.fromFile( tempFile ) );
        return;
    }

    // Show progress dialog while downloading
    final ProgressDialog progress = ProgressDialog.show( context, context.getString( R.string.pdf_show_local_progress_title ), context.getString( R.string.pdf_show_local_progress_content ), true );

    // Create the download request
    DownloadManager.Request r = new DownloadManager.Request( Uri.parse( pdfUrl ) );
    r.setDestinationInExternalFilesDir( context, Environment.DIRECTORY_DOWNLOADS, filename );
    final DownloadManager dm = (DownloadManager) context.getSystemService( Context.DOWNLOAD_SERVICE );
    BroadcastReceiver onComplete = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            if ( !progress.isShowing() ) {
                return;
            }
            context.unregisterReceiver( this );

            progress.dismiss();
            long downloadId = intent.getLongExtra( DownloadManager.EXTRA_DOWNLOAD_ID, -1 );
            Cursor c = dm.query( new DownloadManager.Query().setFilterById( downloadId ) );

            if ( c.moveToFirst() ) {
                int status = c.getInt( c.getColumnIndex( DownloadManager.COLUMN_STATUS ) );
                if ( status == DownloadManager.STATUS_SUCCESSFUL ) {
                    openPDF( context, Uri.fromFile( tempFile ) );
                }
            }
            c.close();
        }
    };
    context.registerReceiver( onComplete, new IntentFilter( DownloadManager.ACTION_DOWNLOAD_COMPLETE ) );

    // Enqueue the request
    dm.enqueue( r );
}


public static void askToOpenPDFThroughGoogleDrive( final Context context, final String pdfUrl ) {
    new AlertDialog.Builder( context )
            .setTitle( R.string.pdf_show_online_dialog_title )
            .setMessage( R.string.pdf_show_online_dialog_question )
            .setNegativeButton( R.string.pdf_show_online_dialog_button_no, null )
            .setPositiveButton( R.string.pdf_show_online_dialog_button_yes, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    openPDFThroughGoogleDrive(context, pdfUrl);
                }
            })
            .show();
}

public static void openPDFThroughGoogleDrive(final Context context, final String pdfUrl) {
    Intent i = new Intent( Intent.ACTION_VIEW );
    i.setDataAndType(Uri.parse(GOOGLE_DRIVE_PDF_READER_PREFIX + pdfUrl ), HTML_MIME_TYPE );
    context.startActivity( i );
}

public static final void openPDF(Context context, Uri localUri ) {
    Intent i = new Intent( Intent.ACTION_VIEW );
    i.setDataAndType( localUri, PDF_MIME_TYPE );
    context.startActivity( i );
}

public static boolean isPDFSupported( Context context ) {
    Intent i = new Intent( Intent.ACTION_VIEW );
    final File tempFile = new File( context.getExternalFilesDir( Environment.DIRECTORY_DOWNLOADS ), "test.pdf" );
    i.setDataAndType( Uri.fromFile( tempFile ), PDF_MIME_TYPE );
    return context.getPackageManager().queryIntentActivities( i, PackageManager.MATCH_DEFAULT_ONLY ).size() > 0;
}

// get File name from url
static class GetFileInfo extends AsyncTask<String, Integer, String>
{
    protected String doInBackground(String... urls)
    {
        URL url;
        String filename = null;
        try {
            url = new URL(urls[0]);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.connect();
            conn.setInstanceFollowRedirects(false);
            if(conn.getHeaderField("Content-Disposition")!=null){
                String depo = conn.getHeaderField("Content-Disposition");

                String depoSplit[] = depo.split("filename=");
                filename = depoSplit[1].replace("filename=", "").replace("\"", "").trim();
            }else{
                filename = "download.pdf";
            }
        } catch (MalformedURLException e1) {
            e1.printStackTrace();
        } catch (IOException e) {
        }
        return filename;
    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
    }
    @Override
    protected void onPostExecute(String result) {
        super.onPostExecute(result);
        // use result as file name
    }
}

}

Pobierz kod źródłowy stąd ( Otwórz plik Pdf z Url w Androidzie programowo )

Główna aktywność.java

package com.deepshikha.openpdf;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ProgressBar;

public class MainActivity extends AppCompatActivity {
    WebView webview;
    ProgressBar progressbar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        webview = (WebView)findViewById(R.id.webview);
        progressbar = (ProgressBar) findViewById(R.id.progressbar);
        webview.getSettings().setJavaScriptEnabled(true);
        String filename ="http://www3.nd.edu/~cpoellab/teaching/cse40816/android_tutorial.pdf";
        webview.loadUrl("http://docs.google.com/gview?embedded=true&url=" + filename);

        webview.setWebViewClient(new WebViewClient() {

            public void onPageFinished(WebView view, String url) {
                // do your stuff here
                progressbar.setVisibility(View.GONE);
            }
        });

    }
}