Cómo renderizar un archivo PDF en Android

Android no tiene soporte para PDF en sus bibliotecas. ¿Hay alguna forma de representar archivos PDF en las aplicaciones de Android?

Desde API Level 21 (Lollipop), Android proporciona una clase PdfRenderer :

// create a new renderer
 PdfRenderer renderer = new PdfRenderer(getSeekableFileDescriptor());

 // let us just render all pages
 final int pageCount = renderer.getPageCount();
 for (int i = 0; i < pageCount; i++) {
     Page page = renderer.openPage(i);

     // say we render for showing on the screen
     page.render(mBitmap, null, null, Page.RENDER_MODE_FOR_DISPLAY);

     // do stuff with the bitmap

     // close the page
     page.close();
 }

 // close the renderer
 renderer.close();

Para obtener más información, consulte la aplicación de muestra .

Para las API más antiguas, recomiendo la biblioteca Android PdfViewer , es muy rápida y fácil de usar, con licencia de Apache License 2.0:

pdfView.fromAsset(String)
  .pages(0, 2, 1, 3, 3, 3) // all pages are displayed by default
  .enableSwipe(true)
  .swipeHorizontal(false)
  .enableDoubletap(true)
  .defaultPage(0)
  .onDraw(onDrawListener)
  .onLoad(onLoadCompleteListener)
  .onPageChange(onPageChangeListener)
  .onPageScroll(onPageScrollListener)
  .onError(onErrorListener)
  .enableAnnotationRendering(false)
  .password(null)
  .scrollHandle(null)
  .load();

Tomado de mi blog:

public class MyPdfViewActivity extends Activity {

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    WebView mWebView=new WebView(MyPdfViewActivity.this);
    mWebView.getSettings().setJavaScriptEnabled(true);
    mWebView.getSettings().setPluginsEnabled(true);
    mWebView.loadUrl("https://docs.google.com/gview?embedded=true&url="+LinkTo);
    setContentView(mWebView);
  }
}

He hecho un enfoque híbrido a partir de algunas de las respuestas dadas a esta y otras publicaciones similares:

Esta solución verifica si hay instalada una aplicación de lector de PDF y hace lo siguiente: - Si hay un lector instalado, descargue el archivo PDF en el dispositivo e inicie una aplicación de lector de PDF - Si no hay ningún lector instalado, pregúntele al usuario si desea ver el archivo PDF en línea a través de Google Drive

¡NOTA! Esta solución utiliza la DownloadManagerclase de Android , que se introdujo en API9 (Android 2.3 o Gingerbread). Esto significa que no funciona en Android 2.2 o anterior.

Escribí una publicación de blog al respecto aquí , pero proporcioné el código completo a continuación para completar:

public class 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";

    /**
     * If a PDF reader is installed, download the PDF file and open it in a reader. 
     * Otherwise ask the user if he/she wants to view it in the Google Drive online PDF reader.<br />
     * <br />
     * <b>BEWARE:</b> This method
     * @param context
     * @param pdfUrl
     * @return
     */
    public static void showPDFUrl( final Context context, final String pdfUrl ) {
        if ( isPDFSupported( context ) ) {
            downloadAndOpenPDF(context, pdfUrl);
        } else {
            askToOpenPDFThroughGoogleDrive( context, pdfUrl );
        }
    }

    /**
     * Downloads a PDF with the Android DownloadManager and opens it with an installed PDF reader app.
     * @param context
     * @param 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 );
        // The place where the downloaded PDF file will be put
        final File tempFile = new File( context.getExternalFilesDir( Environment.DIRECTORY_DOWNLOADS ), filename );
        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 );
    }

    /**
     * Show a dialog asking the user if he wants to open the PDF through Google Drive
     * @param context
     * @param pdfUrl
     */
    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 OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    openPDFThroughGoogleDrive(context, pdfUrl); 
                }
            })
            .show();
    }

    /**
     * Launches a browser to view the PDF through Google Drive
     * @param context
     * @param pdfUrl
     */
    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 );
    }
    /**
     * Open a local PDF file with an installed reader
     * @param context
     * @param localUri
     */
    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 );
    }
    /**
     * Checks if any apps are installed that supports reading of PDF files.
     * @param context
     * @return
     */
    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;
    }

}

Descargue el código fuente aquí ( Mostrar archivo PDF dentro de mi aplicación de Android )

Agregue esta dependencia en su Grado: compile 'com.github.barteksc: android-pdf-viewer: 2.0.3'

activity_main.xml

<RelativeLayout android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#ffffff"
    xmlns:android="http://schemas.android.com/apk/res/android" >

    <TextView
        android:layout_width="match_parent"
        android:layout_height="40dp"
        android:background="@color/colorPrimaryDark"
        android:text="View PDF"
        android:textColor="#ffffff"
        android:id="@+id/tv_header"
        android:textSize="18dp"
        android:gravity="center"></TextView>

    <com.github.barteksc.pdfviewer.PDFView
        android:id="@+id/pdfView"
        android:layout_below="@+id/tv_header"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>


    </RelativeLayout>

MainActivity.java

import android.app.Activity;
import android.database.Cursor;
import android.net.Uri;
import android.provider.OpenableColumns;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ImageView;
import android.widget.RelativeLayout;

import com.github.barteksc.pdfviewer.PDFView;
import com.github.barteksc.pdfviewer.listener.OnLoadCompleteListener;
import com.github.barteksc.pdfviewer.listener.OnPageChangeListener;
import com.github.barteksc.pdfviewer.scroll.DefaultScrollHandle;
import com.shockwave.pdfium.PdfDocument;

import java.util.List;

public class MainActivity extends Activity implements OnPageChangeListener,OnLoadCompleteListener{
    private static final String TAG = MainActivity.class.getSimpleName();
    public static final String SAMPLE_FILE = "android_tutorial.pdf";
    PDFView pdfView;
    Integer pageNumber = 0;
    String pdfFileName;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


        pdfView= (PDFView)findViewById(R.id.pdfView);
        displayFromAsset(SAMPLE_FILE);
    }

    private void displayFromAsset(String assetFileName) {
        pdfFileName = assetFileName;

        pdfView.fromAsset(SAMPLE_FILE)
                .defaultPage(pageNumber)
                .enableSwipe(true)

                .swipeHorizontal(false)
                .onPageChange(this)
                .enableAnnotationRendering(true)
                .onLoad(this)
                .scrollHandle(new DefaultScrollHandle(this))
                .load();
    }


    @Override
    public void onPageChanged(int page, int pageCount) {
        pageNumber = page;
        setTitle(String.format("%s %s / %s", pdfFileName, page + 1, pageCount));
    }


    @Override
    public void loadComplete(int nbPages) {
        PdfDocument.Meta meta = pdfView.getDocumentMeta();
        printBookmarksTree(pdfView.getTableOfContents(), "-");

    }

    public void printBookmarksTree(List<PdfDocument.Bookmark> tree, String sep) {
        for (PdfDocument.Bookmark b : tree) {

            Log.e(TAG, String.format("%s %s, p %d", sep, b.getTitle(), b.getPageIdx()));

            if (b.hasChildren()) {
                printBookmarksTree(b.getChildren(), sep + "-");
            }
        }
    }

}

Finalmente pude modificar el código de butelo para abrir cualquier archivo PDF en el sistema de archivos de Android usando pdf.js. El código se puede encontrar en mi GitHub

Lo que hice fue modificar el pdffile.jsargumento HTML para leer fileasí:

var url = getURLParameter('file');

function getURLParameter(name) {
return decodeURIComponent((new RegExp('[?|&]' + name + '=' + '([^&;]+?)(&|#|;|$)').exec(location.search)||[,""])[1].replace(/\+/g, '%20'))||null}

Entonces, lo que debe hacer es agregar la ruta del archivo después de index.htmlesto:

Uri path = Uri.parse(Environment.getExternalStorageDirectory().toString() + "/data/test.pdf");
webView.loadUrl("file:///android_asset/pdfviewer/index.html?file=" + path);

Actualice la pathvariable para que apunte a un PDF válido en el sistema de archivos Adroid.

puedes usar un método simple importando

implementation 'com.github.barteksc:android-pdf-viewer:2.8.2'

y el código XML es

<com.github.barteksc.pdfviewer.PDFView
        android:id="@+id/pdfv"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
    </com.github.barteksc.pdfviewer.PDFView>

y simplemente declara y agrega un archivo a una carpeta de activos y simplemente asigna el nombre

   PDFView  pdfView=findViewById(R.id.pdfv);       
    pdfView.fromAsset("agl.pdf").load();

Para agregar un poco de luz a esto, tendría que ir con la solución pdf.js de Mozilla. Aquí está el enlace a una implementación bien escrita de esto: https://bitbucket.org/butelo/pdfviewer/ .

Estas son las ediciones que agregué en mi Actividad de Android:

private String getInternalPDFURL(String interalPDFName){
    return "file:///android_asset/pdfviewer/index.html?pdf=" + interalPDFName + ".pdf";
}

Aquí están las ediciones que hice pdffile.js:

var url = '../' + getPDFURL();

function getPDFURL(){
    var query = window.location.search.substring(1);
    var vars = query.split("=");
    var pdfPage = vars[1];
    return pdfPage;
}

Utilicé el siguiente código para abrir e imprimir el PDF usando Wi-Fi. Estoy enviando todo mi código, y espero que sea útil.

public class MainActivity extends Activity {

    int Result_code = 1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button mButton = (Button)findViewById(R.id.button1);

        mButton.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub

                 PrintManager printManager = (PrintManager)getSystemService(Context.PRINT_SERVICE);
                String jobName =  " Document";
                printManager.print(jobName, pda, null);
            }
        });
    }


    public void openDocument(String name) {

        Intent intent = new Intent(android.content.Intent.ACTION_VIEW);
        File file = new File(name);
        String extension = android.webkit.MimeTypeMap.getFileExtensionFromUrl(Uri.fromFile(file).toString());
        String mimetype = android.webkit.MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension);
        intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

        if (extension.equalsIgnoreCase("") || mimetype == null) {
            // if there is no extension or there is no definite mimetype, still try to open the file
            intent.setDataAndType(Uri.fromFile(file), "text/*");
        }
        else {
            intent.setDataAndType(Uri.fromFile(file), mimetype);
        }

        // custom message for the intent
        startActivityForResult((Intent.createChooser(intent, "Choose an Application:")), Result_code);
        //startActivityForResult(intent, Result_code);
        //Toast.makeText(getApplicationContext(),"There are no email clients installed.", Toast.LENGTH_SHORT).show();
    }


    @SuppressLint("NewApi")
    PrintDocumentAdapter pda = new PrintDocumentAdapter(){

        @Override
        public void onWrite(PageRange[] pages, ParcelFileDescriptor destination, CancellationSignal cancellationSignal, WriteResultCallback callback){
            InputStream input = null;
            OutputStream output = null;

            try {
                String filename = Environment.getExternalStorageDirectory()    + "/" + "Holiday.pdf";
                File file = new File(filename);
                input = new FileInputStream(file);
                output = new FileOutputStream(destination.getFileDescriptor());

                byte[] buf = new byte[1024];
                int bytesRead;

                while ((bytesRead = input.read(buf)) > 0) {
                     output.write(buf, 0, bytesRead);
                }

                callback.onWriteFinished(new PageRange[]{PageRange.ALL_PAGES});
            }
            catch (FileNotFoundException ee){
                //Catch exception
            }
            catch (Exception e) {
                //Catch exception
            }
            finally {
                try {
                    input.close();
                    output.close();
                }
                catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

        @Override
        public void onLayout(PrintAttributes oldAttributes, PrintAttributes newAttributes, CancellationSignal cancellationSignal, LayoutResultCallback callback, Bundle extras){

            if (cancellationSignal.isCanceled()) {
                callback.onLayoutCancelled();
                return;
            }

           // int pages = computePageCount(newAttributes);

            PrintDocumentInfo pdi = new PrintDocumentInfo.Builder("Name of file").setContentType(PrintDocumentInfo.CONTENT_TYPE_DOCUMENT).build();

            callback.onLayoutFinished(pdi, true);
        }
    };
}

De todos modos, no hay una vista previa del documento PDF en la vista web de Android. Si desea obtener una vista previa de base64 pdf. Se requiere una biblioteca de terceros.

construir.

compile 'com.github.barteksc:android-pdf-viewer:2.7.0'

dialog_pdf_viewer

<?xml version="1.0" encoding="utf-8"?>

<!--
  ~ Copyright (c) 2017.
  ~ Samet Öztoprak
  ~ All rights reserved.
  -->

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center_horizontal"
    android:orientation="vertical">

    <ImageView
        android:id="@+id/dialog_pdf_viewer_close"
        style="@style/ExitButtonImageViewStyle"
        android:src="@drawable/popup_exit" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        android:background="@color/white"
        android:orientation="vertical">

        <com.github.barteksc.pdfviewer.PDFView
            android:id="@+id/pdfView"
            android:layout_width="match_parent"
            android:layout_height="match_parent" />

    </LinearLayout>

    <View style="@style/HorizontalLine" />

    <com.pozitron.commons.customviews.ButtonFont
        android:id="@+id/dialog_pdf_viewer_button"
        style="@style/ButtonPrimary2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:padding="15dp"
        android:text="@string/agreed" />

</LinearLayout>

DailogPDFViewer.java

public class DialogPdfViewer extends Dialog {
    PDFView pdfView;
    byte[] decodedString;

    public interface OnDialogPdfViewerListener {
        void onAgreeClick(DialogPdfViewer dialogFullEula);

        void onCloseClick(DialogPdfViewer dialogFullEula);
    }

    public DialogPdfViewer(Context context, String base64, final DialogPdfViewer.OnDialogPdfViewerListener onDialogPdfViewerListener) {
        super(context);

        setContentView(R.layout.dialog_pdf_viewer);
        findViewById(R.id.dialog_pdf_viewer_close).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                onDialogPdfViewerListener.onCloseClick(DialogPdfViewer.this);
            }
        });

        findViewById(R.id.dialog_pdf_viewer_button).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                onDialogPdfViewerListener.onAgreeClick(DialogPdfViewer.this);
            }
        });

        decodedString = Base64.decode(base64.toString(), Base64.DEFAULT);

        pdfView = ((PDFView) findViewById(R.id.pdfView));
        pdfView.fromBytes(decodedString).load();

        setOnKeyListener(new OnKeyListener() {
            @Override
            public boolean onKey(DialogInterface dialog, int keyCode, KeyEvent event) {
                if (keyCode == KeyEvent.KEYCODE_BACK && event.getAction() == KeyEvent.ACTION_DOWN) {
                    onDialogPdfViewerListener.onCloseClick(DialogPdfViewer.this);
                }
                return true;
            }
        });

    }
}