问题
I'm working on large project, so there is some logic for saving application state, and then opening correct activity(fragment) when it comes from background. But anyway, I've found that if user navigates through my app and then minimize it - android opens it from background in different ways in following cases:
- User taps on app icon (behavior: user see home activity, doesn't matter where he was, when application was minimized)
- User select app from android "recent apps" (behavior: user see exactly what he saw, when the application was minimized)
So, what is the difference between launching application from background by this two ways? I always thought, that it is the same mechanism, but, obviously, I was wrong.
Thanks for any answers
回答1:
You should pay atention on the folowing docs Activity and Tasks. In short words: if user start app from recents you will receive onRestart before onStart (without onCreate it means that your app was just "suspended"). You able to save screen state using onSaveInstanceState(). But in general starting from icon and from recents - different application behaviors and you should provide proper code for this ways.
UPD
As described below root cause of unexpected behaviour was additional lunchmode attribute.
回答2:
From what I experience as an Android user, both are same.
The difference we usually see is how we close the app
Press back button until app close /
finish()On this state no matter how we open the apps it will go to the main screen
Press Home button
On this state depend on the app. If the app does not handle any
Activitythe app will same with the first state. But if the app handle something like whenonPause()theActivitythenfinish()the apps, then whatever you open with app icon or recent apps will provide the same result.
Correct me if I am wrong
来源：https://stackoverflow.com/questions/18759047/what-is-the-difference-between-launch-app-from-recent-apps-and-tapping-app-ico