Android ExpandableListView getChildView 未触发

Question

我根据许多教程和一些来自 SO 的错误问题制作了 ExpandableListView。 父列表由两个 TextView 和一个具有标准布局的 ImageButton 组成。子列表由单个 TextView 组成。 数据源来自SQLite数据库，从activity生成到ArrayList。

问题：

即使按钮正常工作，父组列表也能正常工作，但是当我尝试展开时，它不会展开。所以我尝试放一些 Toast 消息，但是在打开活动之后，它看起来像 getChildView() 方法根本没有触发，因为 Toast 消息根本没有显示。

ExpandableListAdapter 类是这样的

public class InventoryListExpandableListAdapter extends BaseExpandableListAdapter {

    private Context context;
    private ArrayList<Inventory> data;
    private HashMap<String, ArrayList<String>> list_data;

    public InventoryListExpandableListAdapter(Context context, ArrayList<Inventory> data, HashMap<String, ArrayList<String>> list_data) {
        this.context = context;
        this.data = data;
        this.list_data = list_data;
    }

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

    @Override
    public int getChildrenCount(int groupPosition) {return list_data.get(data.get(groupPosition)).size();}

    @Override
    public Inventory getGroup(int groupPosition) {return data.get(groupPosition);}

    @Override
    public Object getChild(int groupPosition, int childPosition) {return list_data.get(data.get(groupPosition).getCode()).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 true;}

    @Override
    public View getGroupView(final int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
        if (convertView == null) {
            final Inventory inventory = getGroup(groupPosition);

            convertView = View.inflate(context, R.layout.listview_layout_two_row_delete, null);
            ImageButton btnDelete = (ImageButton)convertView.findViewById(R.id.btnDelete);
            TextView text1 = (TextView)convertView.findViewById(R.id.text1);
            TextView text2 = (TextView)convertView.findViewById(R.id.text2);

            text1.setText(inventory.getCode());
            text2.setText(inventory.getItem());

            btnDelete.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    Toast.makeText(context, "DELETED", Toast.LENGTH_SHORT).show();
                }
            });
        }
        return convertView;
    }

    @Override
    public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
        final String childText = (String)getChild(groupPosition, childPosition);
        LayoutInflater infalInflater = (LayoutInflater) this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        if (convertView == null) {
            convertView = infalInflater.inflate(R.layout.listview_layout_single_text, null);
        }
        Toast.makeText(context, "Make Child number "+String.valueOf(childPosition), Toast.LENGTH_SHORT).show();

        TextView text1 = (TextView)convertView.findViewById(R.id.text1);
        text1.setText(childText);
        return convertView;
    }

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

}

感谢您提供的任何帮助。谢谢。

Answer 1

我花了好几个小时试图找到同样的问题，结果发现这对我来说很简单：

1. GroupView 中有一个 ImageButton，它拦截触摸以展开视图。使用它来修复它：

android:focusable="假" android:focusableInTouchMode="false"

1. 由于组视图未展开，因此没有理由浪费 CPU 周期来获取不会显示的视图。
2. 适配器中与孩子相关的所有方法都没有被调用。

尝试调用expandableListView.expandGroup(0...n)手动展开，看看是否调用了适配器中的子相关方法

Answer 2

我找到了一种不同的方法来调用 getChildView()，当它没有在 ExpandedListAdapter 类中自动调用时。这是一个似乎可以解决问题的快捷方式。我有一个扩展列表视图，其中父组项目是复选框列表。单击复选框可显示子项。这是我编写 getGroupView() 函数的方法。

@Override
public View getGroupView(final int groupPosition, final boolean isExpanded, View convertView, final ViewGroup viewGroup)
{
    if (convertView == null)
    {
        LayoutInflater inflater = (LayoutInflater) m_context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = inflater.inflate(R.layout.expandable_list_milk_type,null);
    }
    final CheckBox cbMilkType = (CheckBox) convertView.findViewById(R.id.cb_milk_type);
    cbMilkType.setText(m_listMilktype.get(groupPosition));

    cbMilkType.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            ExpandableListView expandableListView = (ExpandableListView)viewGroup;
            cbMilkType.toggle();
            if (!isExpanded) {
                expandableListView.expandGroup(groupPosition);
            }
            else {
                expandableListView.collapseGroup(groupPosition);
            }
        }
    });
    return convertView;
}

Answer 3

更改 hasStableIds 方法

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

**请更改您的 getGroupView 方法 :: **

 @Override
 public View getGroupView(final int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
        if (convertView == null) {
            final Inventory inventory = getGroup(groupPosition);

            convertView = View.inflate(context, R.layout.listview_layout_two_row_delete, null);
            }
            ImageButton btnDelete = (ImageButton)convertView.findViewById(R.id.btnDelete);
            TextView text1 = (TextView)convertView.findViewById(R.id.text1);
            TextView text2 = (TextView)convertView.findViewById(R.id.text2);

            text1.setText(inventory.getCode());
            text2.setText(inventory.getItem());

            btnDelete.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    Toast.makeText(context, "DELETED", Toast.LENGTH_SHORT).show();
                }
            });

        return convertView;
    }