ExpandListView实现页面目录并支持点击进行页面跳转

通过折叠expandList实现一个可以实现页面跳转的目录功能

1.设计实体bean，
由于Intent跳转传递的是a.class 类型，故设计了一个属性为Class
2.adapter
扩展BaseExpandableListAdpter实现ExpandableAdapter
注意1：重写isChildSelectable()方法需要返回true，不然不会触发 子Item的点击事件
3.item 中，单层的layout_marginTop实效，需要换成padding_top或者在外边再嵌套一层。
https://blog.csdn.net/achilles12345/article/details/47803233

实体bean结构如下：

public class ExChdBean {
    int icon;
    String name;
    String note;
    Class  nameClass;

    public ExChdBean(int icon, String name, String note, Class nameClass) {
        this.icon = icon;
        this.name = name;
        this.note = note;
        this.nameClass = nameClass;
    }

    public int getIcon() {
        return icon;
    }

    public void setIcon(int icon) {
        this.icon = icon;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getNote() {
        return note;
    }

    public void setNote(String note) {
        this.note = note;
    }

    public Class getNameClass() {
        return nameClass;
    }

    public void setNameClass(Class nameClass) {
        this.nameClass = nameClass;
    }
}

public class ExpandListActivityextends AppCompatActivity {

ArrayListparentList=new ArrayList<>();

    ArrayList>childList =new ArrayList>();

    ExpandableListViewexpandableListView;

    MyExpandAdapteradapter;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_expand_list);

        initData();

        expandableListView=findViewById(R.id.expand_list);

        adapter=new MyExpandAdapter(ExpandListActivity.this,parentList,childList);

        expandableListView.setAdapter(adapter);

        dealManager();

    }

void initData(){

//父级菜单初始化

        parentList.add(new ExParBean(1,"图形"));

        parentList.add(new ExParBean(2,"基本控件"));

        parentList.add(new ExParBean(3,"列表控件")); 

        parentList.add(new ExParBean(4,"自定义控件"));

        //子级菜单初始化

        ArrayList list=new ArrayList<>();

        list.add(new ExChdBean(R.drawable.come_111_se_icon,"图形1","note1",CardViewActivity.class));

        list.add(new ExChdBean(R.drawable.come_111_se_icon,"图形1","note1",CardViewActivity.class));

        list.add(new ExChdBean(R.drawable.come_111_se_icon,"图形1","note1",CardViewActivity.class));

        childList.add(list);

        ArrayList list2=new ArrayList<>();

        list2.add(new ExChdBean(R.drawable.come_112_se_icon,"CardView","android5.0",CardViewActivity.class));

        list2.add(new ExChdBean(R.drawable.come_113_se_icon,"基本控件2","note1",CardViewActivity.class));

        list2.add(new ExChdBean(R.drawable.come_114_se_icon,"基本控件3","note1",CardViewActivity.class));

        childList.add(list2);

        ArrayList list3=new ArrayList<>();

        list3.add(new ExChdBean(R.drawable.come_112_se_icon,"ExpandList","",CardViewActivity.class));

        list3.add(new ExChdBean(R.drawable.come_113_se_icon,"列表控件","note1",CardViewActivity.class));

        list3.add(new ExChdBean(R.drawable.come_114_se_icon,"列表控件","note1",CardViewActivity.class));

        childList.add(list3);

        ArrayList list4=new ArrayList<>();

        list4.add(new ExChdBean(R.drawable.come_112_se_icon,"自定义进度条","",ProgressActivity.class));

        list4.add(new ExChdBean(R.drawable.come_113_se_icon,"自定义圆环","",ViewActivity.class));

        childList.add(list4);

    }

 void dealManager(){

        expandableListView.setOnGroupClickListener(new ExpandableListView.OnGroupClickListener() {
            @Override
            public boolean onGroupClick(ExpandableListView parent, View v, int groupPosition, long id) {
                Toast.makeText(ExpandListActivity.this,parentList.get(groupPosition).getParname(),Toast.LENGTH_SHORT).show();
                Boolean isExpand=expandableListView.isGroupExpanded(groupPosition);
                if (!isExpand){
                    expandableListView.expandGroup(groupPosition);
                    adapter.notifyDataSetChanged();
                }
                return true;
            }
        });
        expandableListView.setOnGroupExpandListener(new ExpandableListView.OnGroupExpandListener() {
            @Override
            public void onGroupExpand(int groupPosition) {
                Boolean isExpand=expandableListView.isGroupExpanded(groupPosition);
                if (!isExpand){
                    expandableListView.expandGroup(groupPosition);
                    adapter.notifyDataSetChanged();
                }
            }
        });
        expandableListView.setOnChildClickListener(new ExpandableListView.OnChildClickListener() {
            @Override
            public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition, long id) {
                Intent intent=new Intent(ExpandListActivity.this,childList.get(groupPosition).get(childPosition).getNameClass());
                startActivity(intent);
                return true;
            }
        });
    }

adapter中的实现：

public class MyExpandAdapter extends BaseExpandableListAdapter {

    Context context;
    ArrayList<ExParBean> parlist;
    ArrayList<ArrayList<ExChdBean>> chdlist;

    public MyExpandAdapter() {
    }


    public MyExpandAdapter(Context context, ArrayList<ExParBean> parlist, ArrayList<ArrayList<ExChdBean>> chdlist) {
        this.context=context;
        this.parlist=parlist;
        this.chdlist=chdlist;
    }


    @Override
    public int getGroupCount() {
        return (parlist!=null)&&parlist.size()>0?parlist.size():0;
    }

    @Override
    public int getChildrenCount(int groupPosition) {
        return (chdlist!=null)&&chdlist.get(groupPosition).size()>0?chdlist.get(groupPosition).size():0;
    }

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

    @Override
    public Object getChild(int groupPosition, int childPosition) {
        return chdlist.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) {
        ParViewHolder parViewHolder;
        if (convertView==null){
            parViewHolder=new ParViewHolder();
            convertView=LayoutInflater.from(context).inflate(R.layout.expend_parant_item,parent,false);
            parViewHolder.tv_index=convertView.findViewById(R.id.tv_par_index);
            parViewHolder.tv_parname=convertView.findViewById(R.id.tv_par_name);
            convertView.setTag(parViewHolder);
        }
        else {
            parViewHolder=(ParViewHolder)convertView.getTag();
        }
        parViewHolder.tv_index.setText(String.valueOf(parlist.get(groupPosition).getParindex()));
        parViewHolder.tv_parname.setText(parlist.get(groupPosition).getParname());
        return convertView;
    }

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

            ChdViewHoider chdViewHoider;
            if (convertView==null){
                chdViewHoider=new ChdViewHoider();
                convertView=LayoutInflater.from(context).inflate(R.layout.expand_child_item,parent,false);
                chdViewHoider.img_icon=convertView.findViewById(R.id.img_icon);
                chdViewHoider.tv_chdname=convertView.findViewById(R.id.tv_child_name);
                chdViewHoider.tv_chdnote=convertView.findViewById(R.id.tv_child_note);
                convertView.setTag(chdViewHoider);
            }
            else {
                chdViewHoider=(ChdViewHoider)convertView.getTag();
            }
            chdViewHoider.img_icon.setImageResource(chdlist.get(groupPosition).get(childPosition).getIcon());
            chdViewHoider.tv_chdname.setText(chdlist.get(groupPosition).get(childPosition).getName());
            if (!TextUtils.isEmpty(chdlist.get(groupPosition).get(childPosition).getNote())){
                chdViewHoider.tv_chdnote.setText(chdlist.get(groupPosition).get(childPosition).getNote());

            }
        return convertView;
    }

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

    class ParViewHolder{
        TextView tv_index;
        TextView tv_parname;
    }

    class ChdViewHoider{
        ImageView img_icon;
        TextView tv_chdname;
        TextView tv_chdnote;//注释
    }
}