停止Android应用程序的所有活动和片段

Question

To disconnect from the application i'm developing, i stop all activities and start the LoginActivity. To do so i'm using the code below. the LoginActivity is started but when i click the back button of my phone, i'm connected again without giving the login and password.

NB: I have also fragments in my app!

Can you help me pllz.

// After logout redirect user to Loing Activity
        Intent i = new Intent(_context, LoginActivity.class);
        // Closing all the Activities
        i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

        // Add new Flag to start new Activity
        i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

        // Staring Login Activity
        _context.startActivity(i);

Answer 1

The call i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP) sets the flag Intent.FLAG_ACTIVITY_CLEAR_TOP in the Intent flags. Then you do this:

    i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

This sets the content of the Intent flags to Intent.FLAG_ACTIVITY_NEW_TASK , thereby clearing the flag Intent.FLAG_ACTIVITY_CLEAR_TOP that you had previously set!

You don't need to use Intent.FLAG_ACTIVITY_NEW_TASK , as this won't actually start a new task (because your activities all have the same taskAffinity ).

Setting Intent.FLAG_ACTIVITY_CLEAR_TOP should be enough to do what you want. However, you will need to make sure that your LoginActivity is still active in the task (ie: you shouldn't have called finish() on it). If your LoginActivity isn't present in the activity stack of your task (because you have already called finish() on it), then Android will just create a new instance of LoginActivity and put it on top of the stack.