Show PDF in Android

In my onCreate() I do this check:

//
// check if we have a PDF viewer, else bad things happen
//
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setType("application/pdf");

List<ResolveInfo> intents = getPackageManager().queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY);

if (intents == null || intents.size() == 0) {
       // display message then...
       finish();
}

On my HTC Desire, this doesn't return a match, even though I have Adobe's PDF viewer. An answer to this question android: open a pdf from my app using the built in pdf viewer mentions that Adobe may not have any public Intents, so the above check will obviously return nothing.

Can anyone verify whether you should be able launch Acrobat from an intent, or is there some other method or PDF viewer to use.

The actual use case is downloading copies of invoices and storing them on local st开发者_高级运维orage using code such as:

 URL url = new URL(data);
 InputStream myInput = url.openConnection().getInputStream();

 FileOutputStream fos = openFileOutput(fname, Context.MODE_WORLD_READABLE);

 // transfer bytes from the input file to the output file
 byte[] buffer = new byte[8192];
 int length;
 while ((length = myInput.read(buffer)) > 0) {
    fos.write(buffer, 0, length);
    progressDialog.setProgress(i++);
 }
 fos.close();

and then to show

// read from disk, and call intent
openFileInput(fname);   // will throw FileNotFoundException

File dir = getFilesDir();       // where files are stored
File file = new File(dir, fname);   // new file with our name

Intent intent = new Intent(Intent.ACTION_VIEW, Uri.fromFile(file));
intent.setType("application/pdf");

startActivity(intent);

Connect your phone to you PC, start Eclipse and open the LogCat. Then download a PDF file with the browser and open it. You should see a line such as (I used the HTC desire):

09-14 17:45:58.152: INFO/ActivityManager(79): Starting activity: Intent { act=android.intent.action.VIEW dat=file:///sdcard/download/FILENAME.pdf typ=application/pdf flg=0x4000000 cmp=com.htc.pdfreader/.ActPDFReader }

Have a go with an explicit intent using the component information. Docs say here:

> component -- Specifies an explicit name of a component class to use for the intent. Normally this is determined by looking at the other information in the intent (the action, data/type, and categories) and matching that with a component that can handle it. If this attribute is set then none of the evaluation is performed, and this component is used exactly as is. By specifying this attribute, all of the other Intent attributes become optional.

Downside is you will be bound to the htc reader. But you could try an implicit intent first and if that fails try the explicit intent as a fallback.

-Copy the following code in your activity. Call the function CopyReadAssets("File_name.pdf") from onCreate() function. Place the File_name.pdf file in assets folder.

private void CopyReadAssets(String pdfname)
{
    AssetManager assetManager = getAssets();
    InputStream in = null;
    OutputStream out = null;
    File file = new File(getFilesDir(), pdfname);
    try
    {
        in = assetManager.open(pdfname);
        out = openFileOutput(file.getName(), Context.MODE_WORLD_READABLE);
        copyFile(in, out);
        in.close();
        in = null;
        out.flush();
        out.close();
        out = null;
    } catch (Exception e)
    {
        Toast.makeText(getApplicationContext(), "Pdf Viewer not installed", Toast.LENGTH_SHORT).show();
    }
    try
    {
    Intent intent = new Intent(Intent.ACTION_VIEW);
    intent.setDataAndType(
            Uri.parse("file://" + getFilesDir() + "/"+pdfname),
            "application/pdf");

    startActivity(intent);
    }catch (Exception e) {
        // TODO: handle exception
        Toast.makeText(getApplicationContext(), "Pdf Viewer not installed" ,Toast.LENGTH_SHORT).show();
    }
}

private void copyFile(InputStream in, OutputStream out) throws IOException
{
    byte[] buffer = new byte[1024];
    int read;
    while ((read = in.read(buffer)) != -1)
    {
        out.write(buffer, 0, read);
    }
}