Case:
In android i use
import {openFile} from "tns-core-modules/utils/utils"
openFile(path)
to open a *.pdf file from downloads folder. This works like charm with one problem.

Problem: a list of all apps which can open a pdf file is opened. If i select google pdf viewer, the file opens correctly. If I close and reopen, again I first have to select the google pdf viewer before the file opens. That is, it doesn't remember my choice.

If I open the same file with the android downloads app, I get an option to to always select google pdf viewer as the app to open this file. This works as intended. Trying openFile again after this option is set still opens the app list and does not open the file at once.
I tried also with other apps which were set as default app in the android settings. Also in that case openFile does not use the setting for the default app: in all cases you must select the app to use first. Only if there is only one app, then it opens at once.

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