安卓二级列表的适配器 带优化的 解决二级列表里添加了自定义view以后不能点击展开的问题

在自定义的item项layout中加入dandroid:descendantFocusability="blocksDescendants"开发中很常见的一个问题，项目中的listview不仅仅是简单的文字，常常需要自己定义listview，自己的Adapter去继承BaseAdapter，在adapter中按照需求进行编写，问题就出现了，可能会发生点击每一个item的时候没有反应，无法获取的焦点。原因多半是由于在你自己定义的Item中存在诸如ImageButton，Button，CheckBox等子控件(也可以说是Button或者Checkable的子类控件)，此时这些子控件会将焦点获取到，所以常常当点击item时变化的是子控件，item本身的点击没有响应。    这时候就可以使用descendantFocusability来解决啦，API描述如下：android:descendantFocusabilityDefines the relationship between the ViewGroup and its descendants when looking for a View to take focus.Must be one of the following constant values. 该属性是当一个为view获取焦点时，定义viewGroup和其子控件两者之间的关系。属性的值有三种：        beforeDescendants：viewgroup会优先其子类控件而获取到焦点        afterDescendants：viewgroup只有当其子类控件不需要获取焦点时才获取焦点        blocksDescendants：viewgroup会覆盖子类控件而直接获得焦点 通常我们用到的是第三种，即在Item布局的根布局加上android:descendantFocusability=”blocksDescendants”的属性就好了下面是适配器:适用于安卓二级列表public class MyElvAdapter extends BaseExpandableListAdapter {private List<Groupbean> grouplist;private List<List<Goodsbean>> childlist;private Context context;public MyElvAdapter(List<Groupbean> grouplist, List<List<Goodsbean>> childlist, Context context) {this.grouplist = grouplist;this.childlist = childlist;this.context = context;}@Overridepublic int getGroupCount() {return grouplist.size();}@Overridepublic int getChildrenCount(int groupPosition) {return childlist.get(groupPosition).size();}@Overridepublic Object getGroup(int groupPosition) {return grouplist.get(groupPosition);}@Overridepublic Object getChild(int groupPosition, int childPosition) {return childlist.get(groupPosition).get(childPosition);}@Overridepublic long getGroupId(int groupPosition) {return groupPosition;}@Overridepublic long getChildId(int groupPosition, int childPosition) {return childPosition;}@Overridepublic boolean hasStableIds() {return false;}@Overridepublic View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {GroupViewholder groupViewholder ;if(convertView == null){groupViewholder = new GroupViewholder();convertView = View.inflate(context, R.layout.groupitem, null);groupViewholder.cb_group = convertView.findViewById(R.id.cb_group);groupViewholder.tv_group = convertView.findViewById(R.id.tv_group);convertView.setTag(groupViewholder);}else{groupViewholder = (GroupViewholder) convertView.getTag();}groupViewholder.cb_group.setChecked(grouplist.get(groupPosition).ischecked);groupViewholder.tv_group.setText(grouplist.get(groupPosition).groupname);return convertView;}@Overridepublic View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {ChildViewholder childviewholder ;if(convertView == null){childviewholder = new ChildViewholder();convertView = View.inflate(context,R.layout.childitem,null);childviewholder.cb_child = convertView.findViewById(R.id.cb_child);childviewholder.tv_child = convertView.findViewById(R.id.tv_child);convertView.setTag(childviewholder);}else {childviewholder = (ChildViewholder) convertView.getTag();}childviewholder.cb_child.setChecked(childlist.get(groupPosition).get(childPosition).ischecked);childviewholder.tv_child.setText(childlist.get(groupPosition).get(childPosition).goodsname);return convertView;}@Overridepublic boolean isChildSelectable(int groupPosition, int childPosition) {return true;}class GroupViewholder{CheckBox cb_group;TextView tv_group;}class ChildViewholder{CheckBox cb_child;TextView tv_child;}}