Activity life cycle

Open directly

OnCreate the method to invoke when the activity is to open (starting)

OnStart the method that is called when the UI of the current activity is visible to the user

Onresume Current activity starts responding to user interaction (the activity gets to the focus call method)

Press the back key

OnPause the current activity loses focus call method (becomes background)

OnStop The current Activity interface The user cannot see the calling method

OnDestroy perform some cleanup operations when the activity is being destroyed

minimizing applications

OnPause

OnStop

Activity life cycle can be divided into 3 types according to the range

1. Full life cycle oncreate create OnStart user visible Onresume Get focus onpasue lose focus OnStop user is not visible ondestory destroyed.

2. Visual life cycle interface always visible to users

OnStart () Visible onresume get focus onpasue lose focus OnStop () User not visible

Onrestart ()

3. Foreground life cycle Onresume-onpause

Screen switching is actually the process of activity destruction and reconstruction.

Workaround

1. Fixed screen orientation

<activity

android:screenorientation= "Portrait"//Vertical screen

android:screenorientation= "Landscape"//Horizontal screen

/>

2. Ignore changes in the screen

<activity

Android:configchange= "Orientation|keyboardhidden|screensize"

/>

Activity life cycle