hello, Ivano!

how can I help you today?

Hallo Mark!

I have a question about my app. How can I make sure that on older devices with low memory my view models don't get destroyed when the activity calls onDestroy function

is onDestroy() being called as part of a configuration change? or is the activity being finished?

hi everyojne

hello, Eric -- I will be with you shortly!

Well, it happens when I open an Image or File picker. When that activity starts my activity calls onDestroy. It's not a configuration change.

no problem

Ciao Eric

is the image or file picker in another app?

No in my app.

but it opens the Android gallery or Camera

"the Android gallery or Camera" are other apps than yours, though

oh, well, in that case yes.

OK, there are three possibilities that I can think of:

1. you have that Developer options setting for "don't keep activities" turned on

2. your process is being terminated due to low memory conditions

3. you are finishing the activity yourself as part of navigating to the other app

in all three of those cases, your viewmodel is supposed to go away

Ahh that 2nd one can indeed be the problem now that I think of it.

and in case #2, you don't have a choice, as your whole process is going away

let me check

this is common on low-memory devices with the camera, as camera apps tend to consume a lot of memory

you cannot keep your viewmodel around, but you can put information in the saved instance state Bundle

and if you are using Google's ViewModel, there is stuff coming up that will help ViewModel integrate with the saved instance state Bundle

One thanks for the clarification

I go to test

let me take a question from Eric while you are testing, and I'll be back with you shortly

Eric: your turn! how can I help you today?

thank you

I have a button that makes a custom bottom sheet appear. Are bottom sheets supposed to be able to appear by swiping up also? Mine cannot do that

bottom sheets usually can be expanded or collapsed via swipe gestures, though I think that's configurable

I haven't used Google's bottom sheet stuff much, so I am fuzzy on the details

im confused about if that's default behavior or not. I read it is swipeable by default but mine can swipe down only

is it already open to the "expanded" height at the outset?

if I tap outside the bottomsheet, or slide it down, does that dismiss the bottomsheet and is memory reclaimed

if the bottom sheet is a dialog, then yes, that should dismiss the dialog

if the bottom sheet is a view in your layout, then AFAIK it is still there in the view hierarchy

the bottom sheet is in another fragment

if it's dismissed I don't think it's possible to bring it back by swiping up

agreed

AFAIK, a regular view bottom sheet has collapsed and expanded heights, and by default the user can swipe between those states

the only "dismiss" scenario that I know of is for BottomSheetDialog/BottomSheetDialogFragment, where the "dismiss" behavior is tied to it being a dialog, not it being a bottom sheet

cool mine extends from BottomSheetDialogFragment

right, so when the user dismisses it, it's gone forever

that's no different than any other dialog, whether wrapped in a DialogFragment or not

do you need to explicitly call dismiss?

if you are looking for the user to be able to expand and collapse the bottom sheet repeatedly, I think you need a non-dialog bottom sheet

I think by default clicking outside the bottom sheet dialog would dismiss the dialog, though I think that is configurable

it does dismiss it but i was wondering about memory cleanup

once the dialog is gone, memory associated with it should get garbage-collected, barring some bug somewhere

again, that's not unique to bottom sheet dialogs

(interesting indeed the internals of Android)

Eric: let me take another question from Ivano, and I'll be back with you shortly

Ivano: back to you! do you have another question?

uncle bob is right when he says a dev should learn assembly as fast as possible, and let the magic disappear

good to know. i was considered that if you called newInstance for every button click you would leak memory but it sounds like if you can't bring it back it's dismissed and its memory eligible for GC

HI Mark thank you very much is working as a charm

(Eric: correct, though consider Leak Canary or something to confirm you're not accidentally holding onto something that prevents the fragment from being GC'd)

it was the first case, my senior activated the developer option to not keep activities

ah, OK

particularly for a file picker, I would be a bit surprised for your process to be terminated quickly

ok thanks mark. bye

personally, I almost never turn on that "don't keep activities" setting, just because of cases like this where I will forget that I have it enabled

I see managing hold phones can be a pain sometimes

sorry, but I am uncertain what "managing hold phones" means

absolutely understandable your choice, I experienced that on my skin today, was stuck more than 4 hours

well getting a lot of bugs from phones a bit older, in particular motorola

but I guess it depends by the code that was not good written

anyway you have been already too kind

I wish you a pleasant day, thank you are a living lifesaver

I'm happy to be useful!

you definitely are and so are your books

bye