You can use flutter_downloader – to download and open the file, path_provider – to access device paths and permission_handler – to handle the device storage permissions . Please customize the following example to download the PDF file and open it in your project. It’s taken from flutter_downloader example.
Read moreHow do I download files from assets folder in flutter?
assetsDir – Path to the files unzipped.
Read moreHow do I download a file from a URL?
Steps to download the file:
Read moreHow do I download an image from URL flutter?
Flutter : Download File/Image From URL In Flutter
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