java - 包含 ListView 的选项卡 fragment 在第二次被选中时为空白

Question

我的应用程序有一个实现 TabListener 类的主要 Activity 。在其中，我可以在 5 个选项卡之间切换。以下是我在主要 Activity 中的管理方式:

@Override
protected void onCreate(Bundle p_SavedInstanceState) 
{
    super.onCreate(p_SavedInstanceState);
    setContentView(R.layout.main_fragment_activity);
    m_User = (User) getIntent().getExtras().getSerializable("User");

    if(m_ActionBar == null)
        m_ActionBar = getSupportActionBar();

    if(m_ActionBar.getTabCount() == 0) 
    {
        m_ActionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

        ActionBar.Tab v_TabModules = m_ActionBar.newTab();
        v_TabModules.setText(" Modulos");
        v_TabModules.setIcon(getResources().getDrawable(R.drawable.ic_menu_copy));
        v_TabModules.setTabListener(this);//new NavigationTab(v_FragmentContainer, v_FragmentManager, new ModulesListFragment()));
        m_ActionBar.addTab(v_TabModules);

        ActionBar.Tab v_TabLocations = m_ActionBar.newTab();
        v_TabLocations.setText(" Comodos");
        v_TabLocations.setIcon(getResources().getDrawable(R.drawable.ic_menu_home));
        v_TabLocations.setTabListener(this);//new NavigationTab(v_FragmentContainer, v_FragmentManager, new LocationsListFragment()));
        m_ActionBar.addTab(v_TabLocations);

        ActionBar.Tab v_TabScenes = m_ActionBar.newTab();
        v_TabScenes.setText("Cenas");
        v_TabScenes.setIcon(getResources().getDrawable(R.drawable.ic_menu_crop));
        v_TabScenes.setTabListener(this);//new NavigationTab(v_FragmentContainer, v_FragmentManager, new ScenesListFragment()));
        m_ActionBar.addTab(v_TabScenes);

        ActionBar.Tab v_TabSchedules = m_ActionBar.newTab();
        v_TabSchedules.setText("Agendamentos");
        v_TabSchedules.setIcon(getResources().getDrawable(R.drawable.ic_menu_schedule));
        v_TabSchedules.setTabListener(this);//new NavigationTab(v_FragmentContainer, v_FragmentManager, new ScheduleListFragment()));
        m_ActionBar.addTab(v_TabSchedules);

        ActionBar.Tab v_TabUser = m_ActionBar.newTab();
        v_TabUser.setText("Usuario");
        v_TabUser.setIcon(getResources().getDrawable(R.drawable.ic_menu_user));
        v_TabUser.setTabListener(this);//new NavigationTab(v_FragmentContainer, v_FragmentManager, new UserFragment()));
        m_ActionBar.addTab(v_TabUser);
    }

    if(p_SavedInstanceState != null) 
    {
        int v_IndexTab = p_SavedInstanceState.getInt("tabIndex");
        m_ActionBar.setSelectedNavigationItem(v_IndexTab);
    }
    else
    {
        m_ActionBar.setSelectedNavigationItem(0);
    }
}

@Override
public void onTabSelected(Tab p_Tab, FragmentTransaction arg1) 
{
    BaseClassGafitFragment v_Fragment = null;
    if(p_Tab.getPosition() == 0) 
        v_Fragment = new ModulesListFragment();
    else if(p_Tab.getPosition() == 1) 
        v_Fragment = new LocationsListFragment();
    else if(p_Tab.getPosition() == 2) 
        v_Fragment = new ScenesListFragment();
    else if(p_Tab.getPosition() == 3) 
        v_Fragment = new ScheduleListFragment();
    else if(p_Tab.getPosition() == 4) 
        v_Fragment = new UserFragment();
    if(v_Fragment != null)
        getSupportFragmentManager().beginTransaction().replace(R.id.main_fragment_activity, v_Fragment).commit();
}

ModulesListFragment、LocationsListFragment、ScenesListFragment 和 ScheduleListFragment 类扩展了 Fragment 类并在内部有一个 ListView。以下是 ModulesListFragment 如何管理此列表的示例:

@Override
public View onCreateView(LayoutInflater p_Inflater, ViewGroup p_Container,
        Bundle p_SavedInstanceState) 
{

    View v_View = p_Inflater.inflate(R.layout.moduleslist_activity, p_Container);
    m_ListView = (ListView) v_View.findViewById(R.id.modules_list_id_list_view);
    m_ListView.setOnItemClickListener(onItemClick());

    return super.onCreateView(p_Inflater, p_Container, p_SavedInstanceState);
}

@Override
public void onResume() 
{
    super.onResume();
    loadModulesFromCache();
}

private void loadModulesFromCache()
{
    ArrayList<AbstractAction> v_ModulesList = new ArrayList<AbstractAction>();
    for (Module v_Module : SocketHandlerService.m_Cache.getModulesList())
        v_ModulesList.add(v_Module);
    for (Waiting v_Waiting : SocketHandlerService.m_Cache.getWaitingList())
        v_ModulesList.add(v_Waiting);
    ActionListAdapter v_Adapter = new ActionListAdapter(getActivity().getLayoutInflater(), v_ModulesList);
    m_ListView.setAdapter(v_Adapter);
}

下面是我的 ActionListAdapter，它扩展了 BaseAdapter 类，如何覆盖 getView 方法:

@Override
public View getView(int p_Position, View p_ConvertView, ViewGroup p_Parent)
{
    ViewHolder v_Holder = new ViewHolder();
    if (p_ConvertView == null)
    {
        p_ConvertView = m_Inflater.inflate(R.layout.module_list_item_module_view, p_Parent, false);
        AbstractAction v_Action = m_ActionList.get(p_Position);
        v_Holder.m_Name = (TextView) p_ConvertView.findViewById(R.id.module_list_item_view_name);
        v_Holder.m_Name.setText(v_Action.getDescription());
        v_Holder.m_Name.setTextColor(Color.WHITE);
        v_Holder.m_Image = (ImageView) p_ConvertView.findViewById(R.id.module_list_item_view_photo);
        v_Holder.m_Image.setImageResource(isRed(p_Position) ? ((AbstractModule)v_Action).getImageDrawableRed() : v_Action.getImageDrawable());
        if (v_Action instanceof Module)
        {
            v_Holder.m_Location = (TextView) p_ConvertView.findViewById(R.id.module_list_item_view_location);
            Location v_Location = SocketHandlerService.m_Cache.getSpecificLocation(((Module) v_Action).getLocationId());
            if (v_Location != null)
            {
                v_Holder.m_Location.setText(v_Location.m_Description);
                v_Holder.m_Location.setTextColor(Color.WHITE);
            }
        }
        p_ConvertView.setTag(v_Holder);
    }
    else 
    {
        v_Holder = (ViewHolder) p_ConvertView.getTag();
    }
    return p_ConvertView;
}

该应用程序最初是为现在是 fragment 的五个类中的每一个使用一个 Activity 构建的，现在为了使用选项卡，我将其迁移到 fragment 实现。该应用程序运行正常，但是当我从一个选项卡更改为另一个选项卡然后返回到前一个选项卡时，listView 就消失了!最后一个没有 listView 的选项卡工作正常，但其他 4 个选项卡仅在第一次被选中时有效。有没有人知道可能会发生什么？我发现有人有类似的问题here和 here但是他们的实现似乎与我的不同，并且由于我现在开始处理 fragment ，所以我无法在他们的代码中解决问题的方法与我的问题之间建立联系......非常感谢任何帮助，我们将及时提供所需的任何进一步信息!提前感谢所有阅读本文的人!

Answer 1

改变

@Override
public View onCreateView(LayoutInflater p_Inflater, ViewGroup p_Container,
        Bundle p_SavedInstanceState) 
{

    View v_View = p_Inflater.inflate(R.layout.moduleslist_activity, p_Container);
    m_ListView = (ListView) v_View.findViewById(R.id.modules_list_id_list_view);
    m_ListView.setOnItemClickListener(onItemClick());

    return super.onCreateView(p_Inflater, p_Container, p_SavedInstanceState);
}

对于

@Override
public View onCreateView(LayoutInflater p_Inflater, ViewGroup p_Container,
        Bundle p_SavedInstanceState) 
{

    View v_View = p_Inflater.inflate(R.layout.moduleslist_activity, p_Container);
    m_ListView = (ListView) v_View.findViewById(R.id.modules_list_id_list_view);
    m_ListView.setOnItemClickListener(onItemClick());

    return v_View;
}

和

@Override
public void onTabSelected(Tab p_Tab, FragmentTransaction arg1) 
{
    BaseClassGafitFragment v_Fragment = null;
    if(p_Tab.getPosition() == 0) 
        v_Fragment = new ModulesListFragment();
    else if(p_Tab.getPosition() == 1) 
        v_Fragment = new LocationsListFragment();
    else if(p_Tab.getPosition() == 2) 
        v_Fragment = new ScenesListFragment();
    else if(p_Tab.getPosition() == 3) 
        v_Fragment = new ScheduleListFragment();
    else if(p_Tab.getPosition() == 4) 
        v_Fragment = new UserFragment();
    if(v_Fragment != null)
        getSupportFragmentManager().beginTransaction().replace(R.id.main_fragment_activity, v_Fragment).commit();
}

对于

public void onTabSelected(Tab p_Tab, FragmentTransaction p_FragmentTransaction) 
{
    BaseClassGafitFragment v_Fragment = null;
    if(p_Tab.getPosition() == 0) 
        v_Fragment = new ModulesListFragment();
    else if(p_Tab.getPosition() == 1) 
        v_Fragment = new LocationsListFragment();
    else if(p_Tab.getPosition() == 2) 
        v_Fragment = new ScenesListFragment();
    else if(p_Tab.getPosition() == 3) 
        v_Fragment = new ScheduleListFragment();
    else if(p_Tab.getPosition() == 4) 
        v_Fragment = new UserFragment();
    if(v_Fragment != null)
        p_FragmentTransaction.replace(R.id.main_fragment_activity, v_Fragment);
}

让我们的代码工作。非常感谢@Luksprog!