在android中更改的选项卡上没有重新启动活动

Question

I am making a activity using Tab-Host. I have two tabs. When I start the tab-Host activity, the tab-Host opens the activity and the life-cycle of the activity is calling but when I changed the tab and again open that previous tab the activity is not getting its callback methods like resume.

Answer 1

I don't think there is any specific reason it should restart. For changing configuration (like rotating the device or sliding out a keyboard) there is a specific trigger because the app needs to deal with the change. But any other process should go according to the Activitvy lifeCycle

When your app goes to the background (looses focus) for any reason you get onPause() called, and when it goes back, your onResume() will be called. This is the same for when you go home and then back to your app, or when you switch activities like that. No new intent or something like that, just going back to the activity.

You should put your code that needs to run in the onResume() .

Answer 2

Do what you need to do in the activity in onResume() instead. That will get called everytime, not just the first time it is created.

http://developer.android.com/reference/android/app/Activity.html#ActivityLifecycle

Answer 3

When you switch from one tab to the other and back, the first tab only gets its onResume method called since it has already had its onCreate called the first time.

You can run the code you like in your onResume method if you want anything specific to happen when it gets focus again.