Opening a pdf using google docs is a bad idea in terms of user experience. It is really slow and unresponsive.
Solution after API 21
Since api 21, we have PdfRenderer which helps converting a pdf to Bitmap.
I've never used it but is seems easy enough.
Solution for any api level
Other solution is to download the PDF and pass it via Intent to a dedicated PDF app which will do a banger job displaying it. Fast and nice user experience, especially if this feature is not central in your app.
Use this code to download and open the PDF
public class PdfOpenHelper {
public static void openPdfFromUrl(final String pdfUrl, final Activity activity){
Observable.fromCallable(new Callable<File>() {
@Override
public File call() throws Exception {
try{
URL url = new URL(pdfUrl);
URLConnection connection = url.openConnection();
connection.connect();
// download the file
InputStream input = new BufferedInputStream(connection.getInputStream());
File dir = new File(activity.getFilesDir(), "/shared_pdf");
dir.mkdir();
File file = new File(dir, "temp.pdf");
OutputStream output = new FileOutputStream(file);
byte data[] = new byte[1024];
long total = 0;
int count;
while ((count = input.read(data)) != -1) {
total += count;
output.write(data, 0, count);
}
output.flush();
output.close();
input.close();
return file;
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
})
.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(new Subscriber<File>() {
@Override
public void onCompleted() {
}
@Override
public void onError(Throwable e) {
}
@Override
public void onNext(File file) {
String authority = activity.getApplicationContext().getPackageName() + ".fileprovider";
Uri uriToFile = FileProvider.getUriForFile(activity, authority, file);
Intent shareIntent = new Intent(Intent.ACTION_VIEW);
shareIntent.setDataAndType(uriToFile, "application/pdf");
shareIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
if (shareIntent.resolveActivity(activity.getPackageManager()) != null) {
activity.startActivity(shareIntent);
}
}
});
}
}
For the Intent to work, you need to create a FileProvider to grant permission to the receiving app to open the file.
Here is how you implement it:
In your Manifest:
<provider
android:name="android.support.v4.content.FileProvider"
android:authorities="${applicationId}.fileprovider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/file_paths" />
</provider>
Finally create a file_paths.xml file in the resources foler
<?xml version="1.0" encoding="utf-8"?>
<paths>
<files-path name="shared_pdf" path="shared_pdf"/>
</paths>
Hope this helps =)