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如何重写ExpandableListView的子级ListView

[英]How to override the child listview of a ExpandableListView

我希望ExpandableListView的子级在滚动视图中显示。 如果在一个组项目上有10条以上的评论,我希望能够在不滚动主屏幕的情况下滚动浏览孩子。

我曾尝试使用谷歌搜索,但发现的只是关于可扩展列表的标准教程。 我确实读过ExpandableListView对其子元素使用ListView,所以我认为我应该能够覆盖列表的布局,但是我不知道从哪里开始。

你们能指出我正确的方向吗?

为此,您将需要几节课,所以我将重点放在其中,只给您。

import java.util.List;
import java.util.Map;

import android.app.Activity;
import android.content.Context;
import android.graphics.Typeface;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.TextView;

public class ItemsExpandableListAdapter extends BaseExpandableListAdapter {

 private Activity context;
    private Map<String, List<String>> ItemsCategoryCollections;
    private List<String> ItemsCategories;

    public ItemsExpandableListAdapter(Activity context, List<String> Categories,
            Map<String, List<String>> CategoryCollections) {
        this.context = context;
        this.ItemsCategoryCollections = CategoryCollections;
        this.ItemsCategories = Categories;
    }

    public Object getChild(int groupPosition, int childPosition) {
        return ItemsCategoryCollections.get(ItemsCategories.get(groupPosition)).get(childPosition);
    }

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

    public View getChildView(final int groupPosition, final int childPosition,
            boolean isLastChild, View convertView, ViewGroup parent) {
        final String Itemscategory = (String) getChild(groupPosition, childPosition);
        LayoutInflater inflater = context.getLayoutInflater();

        if (convertView == null) {
            convertView = inflater.inflate(R.layout.items_child_item, parent, false);
        }


        return convertView;
    }

    public int getChildrenCount(int groupPosition) {
        return ItemsCategoryCollections.get(ItemsCategories.get(groupPosition)).size();
    }

    public Object getGroup(int groupPosition) {
        return ItemsCategories.get(groupPosition);
    }

    public int getGroupCount() {
        return ItemsCategories.size();
    }

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

    public View getGroupView(final int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
        String ItemsName = (String) getGroup(groupPosition);
        if (convertView == null) {
            LayoutInflater infalInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = infalInflater.inflate(R.layout.items_group_item, parent, false);
        }

        return convertView;
    }

    public boolean hasStableIds() {
        return true;
    }

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

在上面的getChildView方法中,您可以将布局中的视图更改为Listview,然后可以使用Google快速搜索所需的内容来实现所需的Listview类型(我不知道您需要什么,请指定和会进行编辑以满足您的需要)。

在我的ItemsActivity中,我将这样做(我使用的是基于Fragment的系统,而不是Activity类型的类,因此放在正确的OnCreate方法中)

ExpandableListView expListView;
@Override
public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);

    expListView = (ExpandableListView) getActivity().findViewById(R.id.exLstItems);
    final ExpandableListAdapter expListAdapter = new ItemsExpandableListAdapter(getActivity(), groupItemList, ItemCollection);
    expListView.setAdapter(expListAdapter);

    expListView.setOnChildClickListener(new ExpandableListView.OnChildClickListener() {

        @Override
        public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition, long id) {
            if (groupPosition == 0){
                if (childPosition == 0){
                }
            }
         }
    });
}

对于items_child_item.xml,可以轻松实现Listview。

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content" >

<ListView
    android:id="@+id/lstItemsChild"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentLeft="true"
    android:layout_alignParentRight="true"
    android:layout_alignParentTop="true"
    android:gravity="center|left"/>

</RelativeLayout>

如果您感到懒惰/幸运,这里是items.xml文件

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/RelativeLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:paddingLeft="5dp"
android:paddingRight="5dp"
android:paddingTop="5dp" >

<ExpandableListView
    android:id="@+id/exLstItems"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_alignParentLeft="true"
    android:layout_alignParentTop="true"
    android:childDivider="@color/red"
    android:divider="@color/green"
    android:dividerHeight="2dp"
    android:fastScrollEnabled="true"
    android:groupIndicator="@null"
    android:overScrollMode="always"
    android:scrollbars="none"
    android:smoothScrollbar="true" >
</ExpandableListView>

</RelativeLayout>

我假设您知道如何向可扩展视图中添加项目,因此希望对您有所帮助。

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