Android-Tasks and Back Stack

界面焦点和用户焦点

When the current activity starts another, the new activity is pushed on the top of the stack and takes focus.

Activity栈："last in, first out"

When all
activities are removed from the stack, the task no longer exists.

a
new instance of that activity and activity instance.

In this regard, the principal

<activity>

attributes you can use are:

taskAffinity

launchMode

allowTaskReparenting

clearTaskOnLaunch

alwaysRetainTaskState

finishOnTaskLaunch

And the principal intent flags you can use are:

FLAG_ACTIVITY_NEW_TASK

FLAG_ACTIVITY_CLEAR_TOP

FLAG_ACTIVITY_SINGLE_TOP

Activity启动模式：standard，singleTop，singleTask，singleInstance