WIP persist tab state #1168
WIP persist tab state #1168
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This is just some tinkering to resolve #116 and after talking with @bryanstern. Wanna iterate on this more and see if we can make this simpler, and also possibly explore implementing an analogous `RetainedStateHolder`. Another thing this highlights is the fact that we always initially show a progress indicator even when restoring from a loaded state, wonder what we can do to improve that.
| presenter = presenter!!, | ||
| ui = ui!!, | ||
| ) | ||
| } |
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Re: loading. I think the solution here is to do something like having a map of nav items to their presenter state that is instantiated and rememberRetained above this section.
And then have a "presenter facade" which switches state to the presenter state that is currently being shown.
This is effectively what I'm doing in my project.
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It's because we don't retain state for root back stack changes, only back stack additions (effectively).
This has been at the back of my mind for a while (and mildly annoys me every time I use Tivi).
So this change stores the tab index across app starts, but the state of that tab won't be retained if you switch between them.
There is a comment in the code somewhere from when I wrote the retain backstack stuff, let me find it.
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I can't find it now, but I think this might actually be as simple as making buildCircuitContentProviders a bit smarter, and manually retaining any dropped root records.
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Working on this in #1173
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Sadly this did not Just Work when I converted to retained, gonna keep digging |
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I might be missing something here, but all of this is already handled if you put the root screens into the SaveableBackStack, right?
The back stack will automatically save/restore itself, so everything is persisted. I do exactly this in Tivi and it just works™️
Just thinking out loud, as there's a lot of code in this PR. Maybe I'm missing the use case though?
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It doesn't work in this PR's case because content is all swapped inside the tab pager. As far as the backstack's concerned, they're all just one screen ( It actually does work, I just forgot the UI state that we see here is mostly all rememberSaveable from compose UI. |
This is just some tinkering to resolve #116 and after talking with @bryanstern. Wanna iterate on this more and see if we can make this simpler, and also possibly explore implementing an analogous
RetainedStateHolder.Another thing this highlights is the fact that we always initially show a progress indicator even when restoring from a loaded state, wonder what we can do to improve that.
Screen_recording_20240131_182803.mp4