Flutter PDF & Printing for Mobile and Desktop

Status

Planning and getting approach together with code.

Please feel free to add any tips, info you can see or critique the approach.

NOTE: repo is a mess right now :) Doing experiments.

Pipeline

HTML --> FL Widgets --> PDF Widgets --> PDF --> Printer

Notes

Whats the big deal ?

For Mobile and Desktop.

This is the lib: https://github.com/DavBfr/dart_pdf

Its good but just needs a bit more:

Flutter

• Choose Printer before PDF output.
  • Is the wrong way around currently it seems.
• Parametrics for Flutter Widgets
  • When you make a flutter widget you have to provide the PDF Rendering for that Widget. The Standard Flutter Rendering tree is then used for Screen and Printing - its nice.
  • But Layout needs work. Orientation and Sizes, just like we have different Screen sizes, we have different Paper sizes.
• Make examples
  • Test it out.

Desktop Integration

• Use Google Cloud Connector lib.

  • https://github.com/google/cloud-print-connector
  • It has the code to get a Desktops and RaspberryPI’s printer list, options and print spoolers

• Make a Printer dialogue exactly how Google Chrome does it. They had the same issue actually.

  • https://i.stack.imgur.com/pHFNs.png

• Flow:

  • User selects Printer and then options (paper size, etc).
  • Code asks Flutter PDF to rerender. We display Render as a PDF → Raster (GhostScript golang plug can do this) in the right pane. And round and round it goes.
  • When User clicks Print, We pass the PDF to the local print spooler.

There is a Half way house too

• Spit out the PDF and use local PDF Previewer. This sucks though because its spewing medical data onto disk !! Also its breaks the UX experience.