android studio java how to save activity

Android have a pair of methods called onSaveInstanceState and onRestoreInstanceState which are used by Views automatically to save their data.

With stopping and starting an Activity users would be annoyed if input haven been lost. Switching the device from portrait to landscape causes Android to stop and restart the Activity, allowing Activities the opportunity to redraw a screen for the different dimensions.

This diagram presents different states in which an application can be and also methods called in Activity instance by OS when it passes from one state to another. Activity lifecycle is defined by Android OS and it lets you to interact at some specific point via methods. To achieve that in Android, you must be aware about Activity lifecycle. The saved data that the system uses to restore the previous state is called the instance state and is a collection of key-value pairs stored in a Bundle object. And of course, after this pause, the user will want to return to the previous application state before pause. For example, it may me incoming call, or start of any other activity. In an application, it is essential to be able to save user context between pauses. How to save/restore Activity's and Fragment's state Android

Android studio java how to save activity