使用ExpandableListView实现一个时光轴

在许多App上都能看到时光轴的效果，比如携程等等，那么我们今天就利用ExpandableListView来实现一个时光轴效果，先来看看效果图：

效果还是挺简单的，这里我们主要是采用ExpandableListView来实现，关于ExpandableListView的详细使用参见(android开发之ExpandableListView的使用，实现类似QQ好友列表)，我们这里主要介绍这个效果的实现：

先来看看主布局文件：

 <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" >

     <TextView
         android:id="@+id/title_p"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_centerHorizontal="true"
         android:layout_margin="12dp"
         android:gravity="center"
         android:text="2015年11月"
         android:textSize="18sp" />

     <View
         android:id="@+id/hor_div"
         android:layout_width="match_parent"
         android:layout_height="1dp"
         android:layout_below="@id/title_p"
         android:background="#9F79EE" />

     <View
         android:id="@+id/ver_div"
         android:layout_width="1dp"
         android:layout_height="match_parent"
         android:layout_below="@id/hor_div"
         android:layout_marginLeft="70dp"
         android:background="#9F79EE" />

     <TextView
         android:id="@+id/title_c"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_below="@id/hor_div"
         android:layout_marginLeft="60dp"
         android:paddingBottom="12dp"
         android:paddingLeft="18dp"
         android:paddingTop="12dp"
         android:text="时光轴"
         android:textSize="24sp" />

     <ExpandableListView
         android:id="@+id/lv"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:layout_below="@id/title_c"
         android:layout_marginLeft="60dp"
         android:background="@null"
         android:clickable="false"
         android:divider="@null" >
     </ExpandableListView>

 </RelativeLayout>

两条分割线用View来做，整体不难，不多说，看看MainActivity

 public class MainActivity extends Activity {

     private List<TimeLineBean> list;
     private ExpandableListView lv;

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         requestWindowFeature(Window.FEATURE_NO_TITLE);
         setContentView(R.layout.activity_main);
         initData();
         initView();
     }

     private void initView() {
         lv = (ExpandableListView) this.findViewById(R.id.lv);
         lv.setAdapter(new MyAdapter(MainActivity.this, list));
         for (int i = 0; i < list.size(); i++) {
             lv.expandGroup(i);
         }
         lv.setGroupIndicator(null);
         lv.setOnGroupClickListener(new OnGroupClickListener() {

             @Override
             public boolean onGroupClick(ExpandableListView parent, View v, int groupPosition, long id) {
                 return true;
             }
         });
     }

     private void initData() {
         list = new ArrayList<TimeLineBean>();
         List<String> things = new ArrayList<String>();
         things.add("六王毕，四海一；");
         things.add("蜀山兀，阿房出。");
         things.add("覆压三百余里，隔离天日。");
         list.add(new TimeLineBean("11月24日", things));
         things = new ArrayList<String>();
         things.add("骊山北构而西折，");
         things.add("直走咸阳。");
         things.add("二川溶溶，流入宫墙。");
         list.add(new TimeLineBean("11月23日", things));
         things = new ArrayList<String>();
         things.add("五步一楼，十步一阁；");
         things.add("廊腰缦回，");
         list.add(new TimeLineBean("11月22日", things));
         things = new ArrayList<String>();
         things.add("檐牙高啄；");
         things.add("各抱地势，钩心斗角。");
         things.add("盘盘焉，囷囷焉，蜂房水涡，");
         things.add("矗不知乎几千万落！");
         list.add(new TimeLineBean("11月21日", things));
         things = new ArrayList<String>();
         things.add("长桥卧波，未云何龙？");
         things.add("複道行空，不霁何虹？");
         things.add("高低冥迷，不知西东。");
         list.add(new TimeLineBean("11月20日", things));
         things = new ArrayList<String>();
         things.add("歌台暖响，");
         things.add("春光融融；");
         list.add(new TimeLineBean("11月19日", things));
         things = new ArrayList<String>();
         things.add("舞殿冷袖，");
         things.add("风雨凄凄。");
         things.add("一日之内，一宫之间，");
         things.add("而气候不齐。");
         list.add(new TimeLineBean("11月18日", things));
     }
 }

在MainActivity中我们先初始化模拟数据，然后初始化View，初始化View的过程中，通过一个for循环让所有的group展开，然后再屏蔽掉group的点击事件，好了，再来看看Adapter：

 public class MyAdapter extends BaseExpandableListAdapter {

     private Context context;
     private List<TimeLineBean> list;

     public MyAdapter(Context context, List<TimeLineBean> list) {
         this.context = context;
         this.list = list;
     }

     @Override
     public Object getChild(int groupPosition, int childPosition) {
         return list.get(groupPosition).getThings();
     }

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

     @Override
     public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView,
             ViewGroup parent) {
         ChildHolder holder = null;
         if (convertView == null) {
             convertView = LayoutInflater.from(context).inflate(R.layout.child_item, null);
             holder = new ChildHolder();
             holder.tv = (TextView) convertView.findViewById(R.id.ci_thing);
             convertView.setTag(holder);
         } else {
             holder = (ChildHolder) convertView.getTag();
         }
         holder.tv.setText(list.get(groupPosition).getThings().get(childPosition));
         return convertView;
     }

     @Override
     public int getChildrenCount(int groupPosition) {
         return list.get(groupPosition).getThings().size();
     }

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

     @Override
     public int getGroupCount() {
         return list.size();
     }

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

     @Override
     public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
         GroupHolder holder = null;
         if (convertView == null) {
             convertView = LayoutInflater.from(context).inflate(R.layout.group_item, null);
             holder = new GroupHolder();
             holder.tv = (TextView) convertView.findViewById(R.id.gi_date);
             convertView.setTag(holder);
         } else {
             holder = (GroupHolder) convertView.getTag();
         }
         holder.tv.setText(list.get(groupPosition).getDate());
         return convertView;
     }

     @Override
     public boolean hasStableIds() {
         return false;
     }

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

     class GroupHolder {
         TextView tv;
     }

     class ChildHolder {
         TextView tv;
     }

 }

这个Adapter也没啥讲的，大家如果有疑问可以参见 android开发之ExpandableListView的使用，实现类似QQ好友列表 ，这里有ExpandableListView的详细介绍。最后就是两个item文件：

group_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" >

     <View
         android:layout_width="20dp"
         android:layout_height="20dp"
         android:layout_marginTop="22dp"
         android:background="@drawable/circle" />

     <TextView
         android:id="@+id/gi_date"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:paddingBottom="16dp"
         android:paddingLeft="12dp"
         android:paddingTop="18dp"
         android:text="11月24号"
         android:textSize="22sp" />

 </LinearLayout>

child_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="vertical" >

     <TextView
         android:id="@+id/ci_thing"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:paddingLeft="22dp"
         android:paddingTop="8dp"
         android:text="11月24号"
         android:textColor="#999999"
         android:textSize="16sp" />

 </LinearLayout>

每个group_item的前面有一个红色的实心球，这个球我们用shape来绘制，关于shape的使用参见 android开发之shape详解 ：

circle.xml

 <?xml version="1.0" encoding="utf-8"?>
 <shape xmlns:android="http://schemas.android.com/apk/res/android"
     android:shape="oval" >

     <corners android:radius="10dp" />

     <size
         android:height="10dp"
         android:width="10dp" />

     <solid android:color="#FF6A6A" />

 </shape>

好了，这个东西貌似没难度，其实就是ExpandableListView的使用。

Demo下载http://download.csdn.net/detail/u012702547/9297507