Calling finish() removes the activity from activity stack?

问题

I have made an application where I

1. start activity 'Pin' after I start activity A(activity A has noHistory= true, so it will not stay on stack).
2. If no pin has been set up; PinActivity also starts an activity NewPinActivity.
3. After setting pin, NewPinActivity calls finish() and goes back to PinActivity. Where you will give appropriate pin, it will call finish() on it and it will move again to activity A(Since activity A had noHistory=true, so I have to start a new instance of activity A). My problem is, if I press back from activity A, sometimes my NewPinActivity shows up again even if I called finish() on it.

回答1:

No, you should use in a second activity:

        Intent exitIntent = new Intent(this,MainActivity.class);
        exitIntent.setFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP|Intent.FLAG_ACTIVITY_CLEAR_TOP);
        startActivity(exitIntent);
        MainActivity.exitHandler.sendEmptyMessage(0);

and in MainActivity:

    exitHandler = new Handler() {
    public void handleMessage(Message msg) {
        super.handleMessage(msg);
        switch (msg.what) {
        case 0:
            // clear any informations you like here
            MainActivity.this.finish();
            break;
        }
    }
};

回答2:

Sounds like you should be starting NewPinActivity using startActivityForResult. On a successful result PinActivity should launch ActivityA with Intent.FLAG_NEW_INTENT and finish(); itself? Curiously why are you starting your ActivityA with noHistory?

来源：https://stackoverflow.com/questions/25057003/calling-finish-removes-the-activity-from-activity-stack