PDFs

To add PDF support, import the extension library:

implementation("com.github.CalamityDeadshot:coil-pdf:v0.0.5")

settings.gradle.kts:

dependencyResolutionManagement {
    repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
    repositories {
        google()
        mavenCentral()
        maven { url = URI("https://jitpack.io") }
    }
}

And add the decoder to your component registry when constructing your ImageLoader:

ImageLoader.Builder(context)
  .components {
      add(PdfDecoder.Factory())
  }
  .build()

The ImageLoader will automatically detect and decode any PDFs. This library detects PDFs by looking for the %PDF magic bytes of the file or application/pdf content type. This may not be enough, see Limitations.

This library uses PdfRenderer under the hood.

Customizations

Document page

PDFs generally consist of several pages, and you can specify which page to decode by its index:

ImageRequest.Builder(this@MainActivity)
  .data(<your data>)
  .pdfPage(1)
  .build()

If page index is out of bounds, PdfDecoder throws an IllegalArgumentException. Default is 0.

Document background color

You can specify a background color for a page like this:

ImageRequest.Builder(this@MainActivity)
  .data(<your data>)
  .pdfBackground(Color.White.toArgb())
  .build()

Default is White (0xFFFFFFFF)

Render mode

PdfRenderer allows for two rendering modes: for display and for printing. You can specify which mode to use:

ImageRequest.Builder(this@MainActivity)
  .data(<your data>)
  .pdfRenderMode(PdfRenderMode.FOR_PRINT)
  .build()

Default is PdfRenderMode.FOR_DISPLAY

Limitations

• In the real world a lot of PDF processors used to produce PDF files that break the Adobe PDF specification by not including %PDF bytes in the beginning of the file. This library does not perform error correction of any kind, so if you are loading a PDF from network, and application/pdf content type is not specified, and it is malformed in previously descibed way, PdfDecoder will decide that it is not applicable for this Source.

• Decoded PDF pages are not interactive. This library is intended to be used for simple preview use-cases.

License

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.