最小化和还原应用程序后如何还原正确的视图状态？

Question

I try to use Mosby. But I have one problem.

I have Activity (view), presenter, model, and viewState. On activity I have button. When I click on button I call the method from presenter to load data:

presenter.loadData()

Method that load data call 2 methods:

1. view.showProgress

2. model.getData()

Method model.getData() create ASYNC http request (Retrofit). After request finish than presenter call method from view, view.hideProgress() .

OK. This scheme works fine.

But I have one problem. Steps:

1.Click button on view

2. presenter.loadData()

3.In presenter call view.showProgress() and start async http request

4.Minimize application

5.Activity is destroy

6.As result on viewState call method saveInstanceState() to save current state of view (progress is show)

7.After 5 seconds the network request was finished and presenter try to call view.hideProgress()

8.But Activity does not exist and as result, nothing happened.

9.User return to application

10. As result call method in viewState restoreInstanceState()

11. And as result progress show again, because this state saved on viewState (see item 6).

The problem is that the progress must be hidden because network request was successfully finished when application was minimized (not visible for the user).

How can I fix problem?

Answer 1

When you receive HTTP response you should store it somewhere, for example, it can be repository which stores in memory, or maybe some local storage. Then when you call model.getData() you should check if data is already saved, return this data from the model (and if needed send one more HTTP request to get fresher data) if there is no saved data - send HTTP request. So now, when activity opens you invoke presenter.getData() , it calls view.showProgress() inside and model.getData() , model returns some cached data (if available) and presented calls view.hideProgress()