pdfium

Readium Adapter for PdfiumAndroid and AndroidPdfViewer

PdfiumAndroid is an open source library for rendering PDF documents. This adapter provides an implementation of Readium's PdfDocument for parsing a PDF publication, and of PdfDocumentFragment to render a PDF with PdfNavigatorFragment. LCP protected PDFs are supported, although bound to available device memory.

PdfiumAndroid is free and performant, but has a number of downsides:

• It is currently unmaintained.
• LCP protected PDFs are limited by the device memory. In practice, this library seems to fail to render a .lcpdf of ~40 MB.

A better alternative when possible is to use the commercial library PSPDFKit.

Setup

Follow the same setup instructions as the core Readium toolkit, then add this new dependency in your app's build.gradle.

dependencies {
    implementation "com.github.readium.kotlin-toolkit:readium-adapter-pdfium:$readium_version"
    // Or, if you need only the parser but not the navigator:
    implementation "com.github.readium.kotlin-toolkit:readium-adapter-pdfium-document:$readium_version"
}

Parse a PDF into a Readium Publication.

To open a PDF publication with PdfiumAndroid, initialize the Streamer with the adapter factory:

val streamer = Streamer(context,
    pdfFactory = PdfiumDocumentFactory(context)
)

val publication = streamer.open(FileAsset(pdfFile)).getOrThrow()

Render a PDF with Readium's PdfNavigatorFragment.

To render the PDF using Readium's PdfNavigatorFragment, instantiate PdfiumEngineProvider and use the PdfNavigatorFactory to get a FragmentFactory and a PreferencesEditor.

You can configure AndroidPdfViewer's view manually by providing a listener to the constructor of PdfiumEngineProvider:

pdfEngineProvider = PdfiumEngineProvider(
    listener = object : PdfiumDocumentFragment.Listener {
        override fun onConfigurePdfView(configurator: PDFView.Configurator) {
            configurator.spacing(30)
        }
    }
)