Android导航抽屉显示低级碎片指示器

Question

我有一些问题切换导航抽屉功能到较低级别片段上的功能。我读了这个线程来显示向上的指示器。但当按下按钮时，它将打开导航抽屉，而不是回到以前的片段。并且我不能将EditUserFragment中的操作栏标题设置为“编辑配置文件”。我正在使用Android Studio中提供的导航抽屉模板。

我有三个层次：

1. 包含主页和配置文件项的导航抽屉的主活动
2. 标题为“配置文件”的UserFragment
3. EditUserFragment（较低级别片段）由UserFragment触发

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
    drawerToggle = new ActionBarDrawerToggle(this, drawerLayout,
            R.drawable.ic_launcher, R.string.navigation_drawer_open,
            R.string.navigation_drawer_close);
}

@Override
public void onBackPressed() {
    super.onBackPressed();
    // this won't change the drawer indicator back
    drawerToggle.setDrawerIndicatorEnabled(true);
    // this works
    drawerLayout.setDrawerLockMode(DrawerLayout.LOCK_MODE_UNLOCKED);
}

public void onSectionAttached(int number) {
    // Show the corresponding title on the action bar when clicked and open corresponding
    // fragments.
    Fragment fragment = null;

    switch (number) {
        case 1:
            mTitle = getString(R.string.title_home);
            break;
        case 2:
            mTitle = getString(R.string.title_profile);
            fragment = new UserFragment();
            break;
    }

    if (fragment != null) {
        FragmentManager fragmentManager = getFragmentManager();
        fragmentManager.beginTransaction().replace(R.id.container, fragment).commit();
    }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    if (!mNavigationDrawerFragment.isDrawerOpen()) {
        // Only show items in the action bar relevant to this screen
        // if the drawer is not showing. Otherwise, let the drawer
        // decide what to show in the action bar.
        getMenuInflater().inflate(R.menu.main, menu);
        restoreActionBar();
        return true;
    }
    return super.onCreateOptionsMenu(menu);
}

public void restoreActionBar() {
    ActionBar actionBar = getActionBar();
    actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
    actionBar.setTitle(mTitle);
}

public void setActionBarTitle(String title){
    getActionBar().setTitle(title);
    Log.d("Title 2", getActionBar().getTitle().toString());
}

当我按下电话上的“后退”按钮（而不是操作栏上的“向上”按钮）时，onbackpressed正在部分工作（在代码中注释）。

用户碎片

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    setHasOptionsMenu(true);

    // Inflate the layout for this fragment
    View view = inflater.inflate(R.layout.fragment_profile, container, false);

    drawerLayout = (DrawerLayout) getActivity().findViewById(R.id.drawer_layout);
    drawerToggle = new ActionBarDrawerToggle(getActivity(), drawerLayout,
            R.drawable.ic_launcher, R.string.navigation_drawer_open,
            R.string.navigation_drawer_close);

    return view;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    int id = item.getItemId();
    switch (id) {
        case R.id.action_edit:
            drawerToggle.setDrawerIndicatorEnabled(false);
            // Disable sliding from edge to open drawer
            drawerLayout.setDrawerLockMode(DrawerLayout.LOCK_MODE_LOCKED_CLOSED);
            getFragmentManager().beginTransaction()
                    .replace(R.id.container, new EditUserFragment())
                    .setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE)
                    .addToBackStack(null)
                    .commit();
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}

EditUserFragment

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setHasOptionsMenu(true);
    getActivity().getActionBar().setDisplayHomeAsUpEnabled(true);
    ((MainActivity) getActivity()).setActionBarTitle("Edit Profile");
    Log.d("Title", getActivity().getActionBar().getTitle().toString());
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Get item selected and deal with it
    Log.d("KEY: ", String.valueOf(item.getItemId()));
    switch (item.getItemId()) {
        case android.R.id.home:
            Log.d("EditUserFragment", "I'm here");
            getActivity().onBackPressed();
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}

我想要实现的是能够通过点击向上指示器（现在向上指示器打开了导航抽屉）从edituserfragment返回到userfragment。并在edituserfragment中显示正确的标题。

非常感谢任何帮助！！

Answer 1

经过几天的分析，我发现问题是我在创建时使用了内置的导航抽屉活动。内置将任务分成两个。MainActivity和NavigationDrawerFragment。因此，我在mainactivity中的drawertoggle与在navigationdrawerfragment中的真正的drawertoggle不同。

通常，mainactivy调用navigationdrawerfragment来设置导航抽屉所需的所有内容。我通过在我的mainactivity中实现导航抽屉来解决这一问题，因此我只有一个drawertoggle。但是，如果在navigationdrawerfragment而不是mainactivity中包含所有内容（导航抽屉变量），我仍然无法找到使其工作的方法。如果有人知道答案，欢迎留言！