Question

展开式视图不会创建所有标题和子项的列表，只显示一个没有子项的组标题，只显示向下箭头。点击它只是显示箭头而没有别的。

public class CategoryWise extends AppCompatActivity {

ExpandableListAdapter expandableListAdapter;
ExpandableListView expandableListView;
List<String> listDataHeader;
HashMap<String,List<String>> listDataChild;
DataBaseClass db;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_category_wise);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    expandableListView = (ExpandableListView)findViewById(R.id.ExpandableCategory);
    prepareListData();
    expandableListAdapter = new ExpandableListAdapter(this,listDataHeader,listDataChild);
    expandableListView.setAdapter(expandableListAdapter);


}

public void prepareListData()
{
    listDataHeader = new ArrayList<>();
    listDataChild = new HashMap<String, List<String>>();

    // Adding child data
    listDataHeader.add("Top 250");
    listDataHeader.add("Now Showing");
    listDataHeader.add("Coming Soon..");

    // Adding child data
    List<String> top250 = new ArrayList<String>();
    top250.add("The Shawshank Redemption");
    top250.add("The Godfather");
    top250.add("The Godfather: Part II");
    top250.add("Pulp Fiction");
    top250.add("The Good, the Bad and the Ugly");
    top250.add("The Dark Knight");
    top250.add("12 Angry Men");

    List<String> nowShowing = new ArrayList<String>();
    nowShowing.add("The Conjuring");
    nowShowing.add("Despicable Me 2");
    nowShowing.add("Turbo");
    nowShowing.add("Grown Ups 2");
    nowShowing.add("Red 2");
    nowShowing.add("The Wolverine");

    List<String> comingSoon = new ArrayList<String>();
    comingSoon.add("2 Guns");
    comingSoon.add("The Smurfs 2");
    comingSoon.add("The Spectacular Now");
    comingSoon.add("The Canyons");
    comingSoon.add("Europa Report");

    listDataChild.put(listDataHeader.get(0), top250); // Header, Child data
    listDataChild.put(listDataHeader.get(1), nowShowing);
    listDataChild.put(listDataHeader.get(2), comingSoon);
  }
}

这个ExpandableListAdapter类如下

public class ExpandableListAdapter extends BaseExpandableListAdapter{

private Context _context;
private List<String> _listDataHeader;
private HashMap<String,List<String>> _listChildData;

public ExpandableListAdapter(Context context, List<String> listDataHeader,
                             HashMap<String,List<String>> listChildData)
{
    this._context = context;
    this._listDataHeader = listDataHeader;
    this._listChildData  = listChildData;

}

@Override
public int getGroupCount() {
    return this._listDataHeader.size();
}

@Override
public int getChildrenCount(int groupPosition) {
    return this._listChildData.get(this._listDataHeader.get(groupPosition))
            .size();
}

@Override
public Object getGroup(int groupPosition) {
    return this._listDataHeader.get(groupPosition);
}

@Override
public Object getChild(int groupPosition, int childPosition) {
    return this._listChildData.get(this._listDataHeader.get(groupPosition)).get(childPosition);
}

@Override
public long getGroupId(int groupPosition) {
    return groupPosition;
}

@Override
public long getChildId(int groupPosition, int childPosition) {
    return childPosition;
}

@Override
public boolean hasStableIds() {
    return false;
}

@Override
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {

        String headerTitle = (String) getGroup(groupPosition);
        if (convertView == null) {
            LayoutInflater infalInflater = (LayoutInflater) this._context
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = infalInflater.inflate(R.layout.list_group, null);
        }

        TextView lblListHeader = (TextView) convertView
                .findViewById(R.id.lblListHeader);
        lblListHeader.setTypeface(null, Typeface.BOLD);
        lblListHeader.setText(headerTitle);

        return convertView;
}

@Override
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {


        final String childText = (String) getChild(groupPosition,childPosition);

        if (convertView == null) {
            LayoutInflater infalInflater = (LayoutInflater) this._context
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = infalInflater.inflate(R.layout.list_item, null);
        }

        TextView txtListChild = (TextView) convertView
                .findViewById(R.id.lblListItem);

        txtListChild.setText(childText);
        return convertView;
}

@Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
    return true;
}
}

当我无法找到解决方案时，我尝试了here中的代码请帮忙。

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

<TextView
    android:id="@+id/lblListItem"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:textSize="17dip"
    android:paddingTop="5dp"
    android:paddingBottom="5dp"
    android:paddingLeft="?android:attr/expandableListPreferredChildPaddingLeft" />

</LinearLayout>

ExpandableListView未显示所有标题和子标

0 个答案: