Finish old activity and start a new one or vice versa
I know, that I get the same result with both code snippets
I’d like to know your opinion, if there is a big difference between them. Is one better than the other? If so, why?
6 Solutions collect form web for “Finish old activity and start a new one or vice versa”
When you do startActivity(), all that does is post your intent in a queue of events. The actual starting of the activity happens asynchronously in the near future. So I don’t see a big difference between the two.
The animation is clearly different (at least on 4.1 onwards). Calling
finish() first starts to fade away the first activity earlier and you can briefly see a black background before the new activity fades in. Calling
startActivity() first fades in the new activity on top of the old one and the black background is not visible.
I would do the second choice, I’m not backing this on anything that I have looked up from official sources, but, it makes more sense to launch the new activity before you call finish, that way the new activity pops up via an intent, and the now background activity can call all its cleaning up methods.
If you were to do it the other way around, maybe the intent wont have time to fire before the cleaning up is done. I.e. will the activity call startActivity() after the finish() call?
I hope you understand what I’m trying to state, I would do the second option just to be safe.
In addition to the Emmanuels answer:
finish will be scheduled after the end of the invoking method, since both are processed by the UI thread.
I had the similar issue:
Activity A: singleInstance Activity B: singleInstance Activity C: singleInstance A starts B B starts C C wants to start A:
here if I use:
something wired happens: Activity B comes to foreground instead of A!
but if I change the code like this:
everything seems ok and Activity A comes visible.
I don’t know what’s the problem, but it seems that in the first case, C is finished before executing the startActivity command so that the back stack handles the situation and shows its top activity which is B!
but in the second case, everything happens normally.
I usually do
finish() as I think that’d make sure the new screen comes out before the previous goes out.
I have a login page in my app. After user login successfully, the login activity is gone and main activity is up. It works fine in the Android 4.
Today I wanted to rewrite it in Material design. However, I got a big problem. New Android studio creates blank activity with material design which I think takes many resources. The same process, but I got the error
11-26 18:20:44.450 18397-18397/? I/Choreographer: Skipped 42 frames! The application may be doing too much work on its main thread. 11-26 18:20:44.485 18397-18408/? I/art: Background partial concurrent mark sweep GC freed 2864(191KB) AllocSpace objects, 4(43MB) LOS objects, 13% free, 100MB/116MB, paused 8.056ms total 39.767ms
It said my apps takes many resources when
mainActivity starts in my phone logcat. I have nothing in
mainActivity just that it is the default Material Design layout.
I reversed the order and now it works without error on my phone.