How to render PDF in Android

Question

In my application I will receive a byte stream and convert it to a pdf file in the phone memory. How do I render that to a pdf? And show it on an activity?

Answer 1

Android-Lollipop (api 21) introduce a new API : PdfRenderer

This API allows you to create a Bitmap from a page in a PDF document.

Shortly :

• get a seekable file descriptor from your pdf document :

    ParcelFileDescriptor fd = ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY)
  

• create the PdfRenderer

    PdfRenderer renderer = new PdfRenderer(fd);
  

• prepare the Bitmap

    Bitmap bitmap = Bitmap.createBitmap(WIDTH, HEIGHT, Bitmap.Config.ARGB_4444);
  

• get the PdfRenderer.Page to render

    PdfRenderer.Page page = renderer.openPage(pageIndex);
  

• render the page on the prepared bitmap

    page.render(bitmap, null, null, PdfRenderer.Page.RENDER_MODE_FOR_DISPLAY);
  

• now you can do what you want with the bitmap.

• note that the 2 null args may allow you to clip some portion in the page and perform a transformation (using a Matrix) of the clip

• there is another rendering mode : RENDER_MODE_FOR_PRINT. If you need this mode there are some guidelines to use it properly : here are the details.