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  • Android studio ExpandableListView(可折叠列表)的基本使用

    1.相关属性

    • android:childDivider:指定各组内子类表项之间的分隔条,图片不会完全显示, 分离子列表项的是一条直线
    • android:childIndicator:显示在子列表旁边的Drawable对象,可以是一个图像
    • android:childIndicatorEnd:子列表项指示符的结束约束位置
    • android:childIndicatorLeft:子列表项指示符的左边约束位置
    • android:childIndicatorRight:子列表项指示符的右边约束位置
    • android:childIndicatorStart:子列表项指示符的开始约束位置
    • android:groupIndicator:显示在组列表旁边的Drawable对象,可以是一个图像
    • android:indicatorEnd:组列表项指示器的结束约束位置
    • android:indicatorLeft:组列表项指示器的左边约束位置
    • android:indicatorRight:组列表项指示器的右边约束位置
    • android:indicatorStart:组列表项指示器的开始约束位置

    2.实现ExpandableAdapter的三种方式

    1. 扩展BaseExpandableListAdpter实现ExpandableAdapter。

    2. 使用SimpleExpandableListAdpater将两个List集合包装成ExpandableAdapter

    3. 使用simpleCursorTreeAdapter将Cursor中的数据包装成SimpleCuroTreeAdapter 本节示例使用的是第一个,扩展BaseExpandableListAdpter,我们需要重写该类中的相关方法, 下面我们通过一个代码示例来体验下!


    3.代码示例

    我们来看下实现的效果图

    下面我们就来实现上图的这个效果:

    核心是重写BaseExpandableListAdpter,其实和之前写的普通的BaseAdapter是类似的, 但是BaseExpandableListAdpter则分成了两部分:组和子列表,具体看代码你就知道了!

    另外,有一点要注意的是,重写isChildSelectable()方法需要返回true,不然不会触发 子Item的点击事件!下面我们来写写:

    首先是组和子列表的布局:

    item_exlist_group.xml

    <?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="horizontal"
        android:padding="5dp">
    
        <TextView
            android:id="@+id/tv_group_name"
            android:layout_width="match_parent"
            android:layout_height="56dp"
            android:gravity="center_vertical"
            android:paddingLeft="30dp"
            android:text="AP"
            android:textStyle="bold"
            android:textSize="20sp" />
    
    </LinearLayout>

    item_exlist_item.xml

    <?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="horizontal"
        android:padding="5dp"
        android:background="#6BBA79">
    
        <ImageView
            android:id="@+id/img_icon"
            android:layout_width="48dp"
            android:layout_height="48dp"
            android:src="@mipmap/iv_lol_icon1"
            android:focusable="false"/>
    
        <TextView
            android:id="@+id/tv_name"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="15dp"
            android:layout_marginTop="15dp"
            android:focusable="false"
            android:text="提莫"
            android:textSize="18sp" />
    
    </LinearLayout>

    然后是自定义的Adapter类:

    MyBaseExpandableListAdapter.java

    /**
     * Created by Jay on 2015/9/25 0025.
     */
    public class MyBaseExpandableListAdapter extends BaseExpandableListAdapter {
    
        private ArrayList<Group> gData;
        private ArrayList<ArrayList<Item>> iData;
        private Context mContext;
    
        public MyBaseExpandableListAdapter(ArrayList<Group> gData,ArrayList<ArrayList<Item>> iData, Context mContext) {
            this.gData = gData;
            this.iData = iData;
            this.mContext = mContext;
        }
    
        @Override
        public int getGroupCount() {
            return gData.size();
        }
    
        @Override
        public int getChildrenCount(int groupPosition) {
            return iData.get(groupPosition).size();
        }
    
        @Override
        public Group getGroup(int groupPosition) {
            return gData.get(groupPosition);
        }
    
        @Override
        public Item getChild(int groupPosition, int childPosition) {
            return iData.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;
        }
    
        //取得用于显示给定分组的视图. 这个方法仅返回分组的视图对象
        @Override
        public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
    
            ViewHolderGroup groupHolder;
            if(convertView == null){
                convertView = LayoutInflater.from(mContext).inflate(
                        R.layout.item_exlist_group, parent, false);
                groupHolder = new ViewHolderGroup();
                groupHolder.tv_group_name = (TextView) convertView.findViewById(R.id.tv_group_name);
                convertView.setTag(groupHolder);
            }else{
                groupHolder = (ViewHolderGroup) convertView.getTag();
            }
            groupHolder.tv_group_name.setText(gData.get(groupPosition).getgName());
            return convertView;
        }
    
        //取得显示给定分组给定子位置的数据用的视图
        @Override
        public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
            ViewHolderItem itemHolder;
            if(convertView == null){
                convertView = LayoutInflater.from(mContext).inflate(
                        R.layout.item_exlist_item, parent, false);
                itemHolder = new ViewHolderItem();
                itemHolder.img_icon = (ImageView) convertView.findViewById(R.id.img_icon);
                itemHolder.tv_name = (TextView) convertView.findViewById(R.id.tv_name);
                convertView.setTag(itemHolder);
            }else{
                itemHolder = (ViewHolderItem) convertView.getTag();
            }
            itemHolder.img_icon.setImageResource(iData.get(groupPosition).get(childPosition).getiId());
            itemHolder.tv_name.setText(iData.get(groupPosition).get(childPosition).getiName());return convertView;}//设置子列表是否可选中@Overridepublicboolean isChildSelectable(int groupPosition,int childPosition){returntrue;}privatestaticclassViewHolderGroup{privateTextView tv_group_name;}privatestaticclassViewHolderItem{privateImageView img_icon;privateTextView tv_name;}}

    PS:存储子列表的数据不一定要用ArrayList<ArrayList>这种,根据自己的需求 定义~

    最后是MainActivity的布局以及Java代码:

    布局文件:activity_main.xml

    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:padding="5dp"
        tools:context=".MainActivity">
    
        <ExpandableListView
            android:id="@+id/exlist_lol"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:childDivider="#E02D2F"/>
    
    </RelativeLayout>

    MainActivity.java

    public class MainActivity extends AppCompatActivity {
    
        private ArrayList<Group> gData = null;
        private ArrayList<ArrayList<Item>> iData = null;
        private ArrayList<Item> lData = null;
        private Context mContext;
        private ExpandableListView exlist_lol;
        private MyBaseExpandableListAdapter myAdapter = null;
    
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            mContext = MainActivity.this;
            exlist_lol = (ExpandableListView) findViewById(R.id.exlist_lol);
    
    
            //数据准备
            gData = new ArrayList<Group>();
            iData = new ArrayList<ArrayList<Item>>();
            gData.add(new Group("AD"));
            gData.add(new Group("AP"));
            gData.add(new Group("TANK"));
    
            lData = new ArrayList<Item>();
    
            //AD组
            lData.add(new Item(R.mipmap.iv_lol_icon3,"剑圣"));
            lData.add(new Item(R.mipmap.iv_lol_icon4,"德莱文"));
            lData.add(new Item(R.mipmap.iv_lol_icon13,"男枪"));
            lData.add(new Item(R.mipmap.iv_lol_icon14,"韦鲁斯"));
            iData.add(lData);
            //AP组
            lData = new ArrayList<Item>();
            lData.add(new Item(R.mipmap.iv_lol_icon1, "提莫"));
            lData.add(new Item(R.mipmap.iv_lol_icon7, "安妮"));
            lData.add(new Item(R.mipmap.iv_lol_icon8, "天使"));
            lData.add(new Item(R.mipmap.iv_lol_icon9, "泽拉斯"));
            lData.add(new Item(R.mipmap.iv_lol_icon11, "狐狸"));
            iData.add(lData);
            //TANK组
            lData = new ArrayList<Item>();
            lData.add(new Item(R.mipmap.iv_lol_icon2, "诺手"));
            lData.add(new Item(R.mipmap.iv_lol_icon5, "德邦"));
            lData.add(new Item(R.mipmap.iv_lol_icon6, "奥拉夫"));
            lData.add(new Item(R.mipmap.iv_lol_icon10, "龙女"));
            lData.add(new Item(R.mipmap.iv_lol_icon12, "狗熊"));
            iData.add(lData);
    
            myAdapter = new MyBaseExpandableListAdapter(gData,iData,mContext);
            exlist_lol.setAdapter(myAdapter);
    
            //为列表设置点击事件
            exlist_lol.setOnChildClickListener(new ExpandableListView.OnChildClickListener() {
                @Override
                public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition,long id){Toast.makeText(mContext,"你点击了:"+ iData.get(groupPosition).get(childPosition).getiName(),Toast.LENGTH_SHORT).show();returntrue;}});}}

     

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  • 原文地址:https://www.cnblogs.com/mjhjl/p/14902199.html
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