SherlockListFragment中的ExpandableListView,带有扩展BaseExpandableListAdapter的自定义适配器

时间:2013-02-21 19:14:05

标签: android listview actionbarsherlock expandablelistview

你好!

我有这个设置。

MainActivity - 扩展SherlockFragmentActivity - 使用TabsAdapter显示4个片段

我遇到其中一个需要的标签问题:

FragmentSkills - 扩展SherlockListFragment - 现在显示一些硬编码测试字符串的ExpandableListView

=============================================== =================================== 问题: 我现在得到一个NullPointerException,我似乎无法旋转:

//在FragmentSkills.java中的onActivityCreated()内部 expandList =(ExpandableListView)getActivity()。findViewById(R.id.ExpList);

=============================================== ===================================

我有点卡在这里,我不知道还有什么可以尝试。我在类似的事情上找到了很多例子,但他们都只是在正常的Activity中展示了如何做到这一点。由于我缺乏经验,这可能是我看不到的小东西所以请看看并尝试帮助我解决这个问题。

我是Android新手,所以请耐心等待我。任何帮助表示赞赏。提前谢谢了。这是相关的代码。如果您需要了解更多信息,请与我们联系。 非常感谢!

fragment_skills.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <ExpandableListView android:id="@+id/ExpList"
        android:layout_height="match_parent"
        android:layout_width="match_parent"
       android:groupIndicator="@null" />

</LinearLayout>

list_item_skill_groups.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <TextView android:id="@+id/tvSkillGroup"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginRight="15dp"
        android:textColor="@color/black"
        android:textIsSelectable="false"
        android:textSize="17sp" />

</LinearLayout>

list_item_skills.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingTop="10dp"
    android:paddingLeft="16dp"
    android:paddingRight="16dp"
    android:paddingBottom="10dp"
    android:orientation="vertical" >

    <TextView android:id="@+id/tvSkillTitle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textIsSelectable="false"
        android:textSize="19sp"
        android:textStyle="normal"
        android:paddingBottom="4dp" />

</LinearLayout>

FragmentSkills.java

public class FragmentSkills extends SherlockListFragment {
    private ExpandableListView expandList;
    private ArrayList<ExpandableSkillsGroup> expListItems;
    private SkillsAdapter skillsAdapter;
    ArrayList<ExpandableSkillsChild> list1;
    ArrayList<ExpandableSkillsChild> list2;
    ArrayList<ExpandableSkillsChild> list3;

    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
        expandList = (ExpandableListView) getActivity().findViewById(R.id.ExpList);
        expListItems = getListItems();
        skillsAdapter = new SkillsAdapter(getActivity(), expListItems);
        expandList.setAdapter(skillsAdapter);
    }

    private ArrayList<ExpandableSkillsGroup> getListItems() {
        list1 = new ArrayList<ExpandableSkillsChild>();
        list1.add(new ExpandableSkillsChild("Android", null));
        list1.add(new ExpandableSkillsChild("Java", null));
        list1.add(new ExpandableSkillsChild("Javascript", null));

        ExpandableSkillsGroup group1 = new ExpandableSkillsGroup("Software Development");
        group1.setItems(list1);

        list2 = new ArrayList<ExpandableSkillsChild>();
        list2.add(new ExpandableSkillsChild("MySQL", null));
        list2.add(new ExpandableSkillsChild("PostgreSQL", null));
        list2.add(new ExpandableSkillsChild("SQLite", null));

        ExpandableSkillsGroup group2 = new ExpandableSkillsGroup("Databases");
        group2.setItems(list2);

        list3 = new ArrayList<ExpandableSkillsChild>();
        list3.add(new ExpandableSkillsChild("MySQL", null));
        list3.add(new ExpandableSkillsChild("PostgreSQL", null));
        list3.add(new ExpandableSkillsChild("SQLite", null));

        ExpandableSkillsGroup group3 = new ExpandableSkillsGroup("Operating Systems");
        group3.setItems(list3);

        ArrayList<ExpandableSkillsGroup> groupList  = new ArrayList<ExpandableSkillsGroup>();
        groupList.add(group1);
        groupList.add(group2);
        groupList.add(group3);
        return groupList;
    }
}

1 个答案:

答案 0 :(得分:0)

首先将FragmentSkills extends SherlockListFragment替换为FragmentSkills extends SherlockFragment,此处不需要SherlockListFragment。现在在FragmentSkills

中添加此方法
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    return inflater.inflate(R.layout.fragment_skills, container, false);
}

也在您的public void onActivityCreated(Bundle savedInstanceState)而不是

    expandList = (ExpandableListView) getActivity().findViewById(R.id.ExpList);

这样做

    expandList = (ExpandableListView) getView().findViewById(R.id.ExpList);