android DrawerLayout导航片段重载不点击DrawerLayout项目

Question

我正在创建具有DrawerLayout导航的简单应用程序。其中一个菜单项是My Profile。在我的个人资料屏幕有按钮打开更改密码屏幕在相同的片段。如果我打开drawlayout的菜单并关闭它而不单击，那么我的个人资料屏幕再次加载。

下面是我的代码

public class HomeActivity extends ActionBarActivity {
private DrawerLayout mDrawerLayout;
private ListView mDrawerList;
private ActionBarDrawerToggle mDrawerToggle;
private CharSequence mDrawerTitle;
private CharSequence mTitle;
private ArrayList<SideMenuEntity> listSideMenuItems;
private SideMenuAdapter adapterSideMenu;
Menu menu;
Fragment fragment;
AsyncTaskHelper loadFragmentTask;
int position, old_position;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_home);
    mTitle = mDrawerTitle = getTitle();
    mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
    mDrawerList = (ListView) findViewById(R.id.list_slidermenu);
    listSideMenuItems = new ArrayList<>();
    for(String str : Constant.SIDE_MENU_ITEMS)
    {
        listSideMenuItems.add(new SideMenuEntity(str));
    }
    // setting the nav drawer list adapter
    adapterSideMenu = new SideMenuAdapter(getApplicationContext(),listSideMenuItems);
    mDrawerList.setAdapter(adapterSideMenu);
    mDrawerList.setOnItemClickListener(new ListView.OnItemClickListener()
    {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id)
        {
            displayView(position);
        }
    });
    ActionBar actionbar = getSupportActionBar();
    actionbar.setDisplayHomeAsUpEnabled(true);
    actionbar.setHomeButtonEnabled(true);
    mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout, R.mipmap.ic_launcher,R.string.app_name, R.string.app_name)
    {
        public void onDrawerClosed(View view) {
            getSupportActionBar().setTitle(mTitle);
            invalidateOptionsMenu();
            if (fragment != null) {
                _setFragmentContainer(fragment, listSideMenuItems.get(position).title);
            }
        }
        public void onDrawerOpened(View drawerView) {
            getSupportActionBar().setTitle(mDrawerTitle);
            // calling onPrepareOptionsMenu() to hide action bar icons
            invalidateOptionsMenu();
        }
    };
    mDrawerLayout.setDrawerListener(mDrawerToggle);
    if (savedInstanceState == null)
    {
        old_position = -1;
        displayView(-1);
        _setFragmentContainer(fragment, listSideMenuItems.get(position).title);
    }
}
@Override
public boolean onCreateOptionsMenu(Menu menu)
{
    this.menu = menu;
    getMenuInflater().inflate(R.menu.menu_home_setting, menu);
    _setActionBarHomeVisible(false);
    return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // toggle nav drawer on selecting action bar app icon/title
    if (mDrawerToggle.onOptionsItemSelected(item)) {
        return true;
    }
    // Handle action bar actions click
    switch (item.getItemId())
    {
        case R.id.title_bar_home:
            displayView(0);
            return true;
        case R.id.title_bar_setting:
            _setFragmentContainer(new SettingFragment(), "Setting");               
        return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}
/***
 * Called when invalidateOptionsMenu() is triggered
 */
@Override
public boolean onPrepareOptionsMenu(Menu menu)
{
    return super.onPrepareOptionsMenu(menu);
}
/**
 * Diplaying fragment view for selected nav drawer list item
 *
 */
protected void displayView(int p)
{
    position = p >= 0 ? p : 0;
    fragment = null;
    switch (position)
    {
        case Constant.SIDE_MENU_ITEM_DAHSHBOARD:
            fragment = new DashboardFragment();               
            break;
        case Constant.SIDE_MENU_ITEM_MY_PROFILE:              
            fragment = new MyProfileFragment();
            break;
    }
    mDrawerList.setItemChecked(position, true);
    mDrawerList.setSelection(position);
    mDrawerLayout.closeDrawer(mDrawerList);
}
@Override
public void setTitle(CharSequence title) {
    mTitle = title;
    getSupportActionBar().setTitle(mTitle);
}
@Override
protected void onPostCreate(Bundle savedInstanceState) {
    super.onPostCreate(savedInstanceState);
    mDrawerToggle.syncState();
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
    super.onConfigurationChanged(newConfig);
    mDrawerToggle.onConfigurationChanged(newConfig);
}
/**-------------- private functions ---------------------*/
public void _setFragmentContainer(Fragment fragment, String title)
{
    FragmentManager fragmentManager = getSupportFragmentManager();
    fragmentManager.beginTransaction().replace(R.id.frame_container, fragment).commit();
    setTitle(title);
}

}

Answer 1

尝试添加超级构造函数:

public void onDrawerClosed(View view) {
    super.onDrawerClosed(view);
    getSupportActionBar().setTitle(mTitle);
    invalidateOptionsMenu();
    if (fragment != null) {
        _setFragmentContainer(fragment, listSideMenuItems.get(position).title);
    }
}
public void onDrawerOpened(View drawerView) {
    super.onDrawerOpened(drawerView);
    getSupportActionBar().setTitle(mDrawerTitle);
    // calling onPrepareOptionsMenu() to hide action bar icons
    invalidateOptionsMenu();
}

Answer 2

我自己解决这个问题。实际上，每当DrawerLayout关闭时，onDrawerClosed事件触发，然后我就在_setFragmentContainer()函数后为fragment变量null

if (fragment != null) 
{
   _setFragmentContainer(fragment, listSideMenuItems.get(position).title);
   fragment = null;
}

现在drawlayout菜单关闭，由于fragment为null，它不会再次加载fragment