android - 再次按返回退出 android studio

Question

如何实现再次按下以退出 android studio，请。在这里查看我的编码。我已经检查了这里有关此的所有讨论，但没有使用我的代码。我必须确保在后按时，始终在关闭前返回主页片段。非常感谢您！

 /**
     * On back pressed, always go to home fragment before closing
     */
    @Override
    public void onBackPressed() {
        //if stack has items left
        if (getSupportFragmentManager().getBackStackEntryCount() == 0) {
            //get current fragment
            Fragment fragment = getSupportFragmentManager().findFragmentById(R.id.mainFragment);

            //only close if in CategoryFragment else go to CategoryFragment
            if (fragment instanceof SearchFragment) {
                finish();
            } else {
                changeFragment(new SearchFragment());
            }
        } else {
            super.onBackPressed();
        }
    }

标签： androidandroid-studioonbackpressed

Answer 1

如果你想再次让 onBackPressed 退出活动，你可以使用这个

public void onBackPressed() {
    count++;
    if (count > 1) {
        moveTaskToBack(true);
    } else {
        showToast("Press back again to Leave!");

        // resetting the counter in 2s
        Handler handler = new Handler();
        handler.postDelayed(new Runnable() {
            @Override
            public void run() {
                count = 0;
            }
        }, 2000);
    }
}