ExpandableListview的三级列表的数据加载及刷新

来源：互联网发布：复杂网络节点介数编辑：程序博客网时间：2024/05/20 03:44

一、ExpandableListView初识

之前对于ExpandableListView的理解并不是很了解，由于最近的项目需要用到才开始认真的去查看下相关的知识，其实 ExpandableListView类似于listview，它同样也有自己的布局适配器，也同样有getView和getConunt方法,可以这么理解，ExpandableListView两个listview的结合，嵌套而已

二、ExpandableListView的初步使用
ExpandableListView有一级适配器和二级适配器，我们来看看一级适配器的代码：

public class ParentAdapter extends BaseExpandableListAdapter{    private Realm realm;    private Context mContext;    private List<ParentEntity> parents;    private List<ParentAdapterEntity> childAdapterLists;    public ParentAdapter(Context mContext, List<ParentEntity> parents, Realm realm, List<ParentAdapterEntity> childAdapterLists) {        this.mContext = mContext;        this.parents = parents;        this.realm = realm;        this.childAdapterLists = childAdapterLists;    }    public void setData(List<ParentEntity> parents, List<ParentAdapterEntity> childAdapterLists) {        this.parents = parents;        this.childAdapterLists = childAdapterLists;        notifyDataSetChanged();    }    public List<ParentEntity> getData(){        return parents;    }    public List<ParentAdapterEntity> getAdapterList(){        return childAdapterLists;    }    @Override    public int getGroupCount() {        return parents != null ? parents.size() : 0;    }    @Override    public int getChildrenCount(int groupPosition) {        return parents.get(groupPosition).getChilds() != null ? parents                .get(groupPosition).getChilds().size() : 0;    }    @Override    public ParentEntity getGroup(int groupPosition) {        return parents.get(groupPosition);    }    @Override    public ChildEntity getChild(int groupPosition, int childPosition) {        return parents.get(groupPosition).getChilds().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;    }    /**     * 根布局     * @param groupPosition     * @param isExpanded     * @param convertView     * @param parent     * @return     */    @Override    public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {        GroupHolder holder = null;        if (convertView == null) {            convertView = LayoutInflater.from(mContext).inflate(R.layout.parent_group_item, null);            holder = new GroupHolder(convertView);            convertView.setTag(holder);        } else {            holder = (GroupHolder) convertView.getTag();        }        if(!isExpanded){            holder.parentGroup_iv.setBackgroundResource(R.mipmap.img_fangda);        }else{            holder.parentGroup_iv.setBackgroundResource(R.mipmap.img_suoxiao);        }       holder.update(parents.get(groupPosition),groupPosition);        return convertView;    }    /**     * 子列表的布局     * @param groupPosition     * @param childPosition     * @param isLastChild     * @param convertView     * @param parent     * @return     */    @Override    public View getChildView(final int groupPosition, final int childPosition, final boolean isLastChild, View convertView, ViewGroup parent) {        final ExpandableListView eListView = getExpandableListView();        final ArrayList<ChildEntity> childs = new ArrayList<ChildEntity>();        final ChildEntity child = getChild(groupPosition, childPosition);        childs.add(child);        final ChildAdapter childAdapter = new ChildAdapter(this.mContext,                childs);        childAdapterLists.get(groupPosition).getChildAdapterEntitys().get(childPosition).setChildAdapter(childAdapter);        //存储每一个adapter用来刷新        eListView.setAdapter(childAdapter);        eListView.setOnGroupClickListener(new ExpandableListView.OnGroupClickListener() {            @Override            public boolean onGroupClick(ExpandableListView parent, View v, int groupPos, long id) {            }        });        /**         * 设置子列表的条目点击事件         * 点击子列表时，调用回调接口         */        eListView.setOnChildClickListener(new ExpandableListView.OnChildClickListener() {            @Override            public boolean onChildClick(ExpandableListView parent, View v, int groupIdex, int childIdex, long id) {            }        });        childAdapterLists.get(groupPosition).getChildAdapterEntitys().get(childPosition).seteListView(eListView);        return eListView;    }    @Override    public boolean isChildSelectable(int groupPosition, int childPosition) {        return false;    }    /**     * getchildview中动态创建子ExpandableListView     * @return     */    public ExpandableListView getExpandableListView() {        final CustomExpandableListView mExpandableListView = new CustomExpandableListView(mContext);        mExpandableListView.setPadding(20,0,0,0);        mExpandableListView.setGroupIndicator(null);// 取消展开折叠的指示图标        return mExpandableListView;    }    /**     * 根布局的viewholder     */    class GroupHolder {        private TextView parentGroupTV;        private ImageView parentGroup_iv;        private ImageView iv_parent_run;        public GroupHolder(View v) {            parentGroupTV = (TextView)v.findViewById(R.id.parentGroupTV);            parentGroup_iv = (ImageView)v.findViewById(R.id.parentGroup_iv);            iv_parent_run = (ImageView)v.findViewById(R.id.iv_parent_run);        }        public void update(ParentEntity model, int groupPosition) {            parentGroupTV.setText(model.getGroupName());           parentGroupTV.setTextColor(Color.parseColor("#6F6F6F"));            if (null != model.getChilds() && model.getChilds().size()>0){                if (model.getChilds().get(0).getChildTaskBean().get(0).isParentRun()){                    iv_parent_run.setVisibility(View.VISIBLE);                }else{                    iv_parent_run.setVisibility(View.INVISIBLE);                }            }else{                RealmResults<ParentEntity> where = realm.where(ParentEntity.class).findAll();                for (ParentEntity parentEntity:where) {                    if (model.getGroupName().equals(parentEntity.getGroupName())){                        if (parentEntity.getChilds().get(0).getChildTaskBean().get(0).isParentRun()){                            iv_parent_run.setVisibility(View.VISIBLE);                        }else{                            iv_parent_run.setVisibility(View.INVISIBLE);                        }                        break;                    }                }            }        }    }

核心代码在于getGroupView和getChildView,三级列表的话在getchildVie中在取创建新的ExpandableListView,然后给当前这个二级条目的ExpandableListView设置他的adpter,这样childadapter的使用就在这里了，我们看下面的核心代码：

/**     * 第二层布局     * @param groupPosition     * @param isExpanded     * @param convertView     * @param parent     * @return     */    @Override    public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {        GroupHolder holder = null;        if (convertView == null) {            convertView = LayoutInflater.from(mContext).inflate(R.layout.child_group_item, null);            holder = new GroupHolder(convertView);            convertView.setTag(holder);        } else {            holder = (GroupHolder) convertView.getTag();        }        if(!isExpanded){            holder.childGroup_iv.setBackgroundResource(R.mipmap.img_fangda);        }else{            holder.childGroup_iv.setBackgroundResource(R.mipmap.img_suoxiao);        }        holder.update(mChilds.get(groupPosition));        return convertView;    }    /**     * 第三层布局     * @param groupPosition     * @param childPosition     * @param isLastChild     * @param convertView     * @param parent     * @return     */    @Override    public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {        ChildHolder holder = null;        if (convertView == null) {            convertView =LayoutInflater.from(mContext).inflate(R.layout.child_child_item, null);            holder = new ChildHolder(convertView);            convertView.setTag(holder);        } else {            holder = (ChildHolder) convertView.getTag();        }        TaskBean taskBean = mChilds.get(groupPosition).getChildTaskBean().get(childPosition);        holder.update(taskBean);        return convertView;    }

在三级列表的实现过程中,项目的需求是要求点击条目后，将当前条目的颜色改变，当时思考这个问题后，考虑定义一个专门用来存放adpter三级集合，分别对应数据集合的每一条数据，这样一来当我们想要刷新某一个条目的时候，我们通过记录当前点击的条目的position，（一级，二级，三级的position）adpter集合找出点击的适配器后，改变对象的颜色，然后调用刷新，还要将上一个点击的颜色修改回来，这里同样也要记录上一个点击的条目，也是调用adpter刷新；还有一个重点就是ExpandableListView调用setOnGroupClickListener的时候，方法会有一个返回boolean值,如果返回true,那么条目将不可展开，这个我们要是想动态的不想展开，可以自己在代码中动态输入后改变；

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