【Android基础入门〖19〗】ExpandableListView酷我音乐界面的下拉菜单

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 *  本博客为CSDN博主【MK】原创，博客地址：http://blog.csdn.net/mkrcpp/article/details/13170649

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研究了一夜，终于完毕，有一种成就感，虽然没什么成就......

• 本以为那种下拉菜单方式是通过嵌套 ExpandableListView 搞定，甚是麻烦，最后因为子 ExpandableListView  的布局总是莫名其妙的多一点而止步。无奈之下，突然意识到我钻了牛角尖，这是好事 :)
• 非常珍惜这些自己研究出来的东西，但是想想这点不过沧海一粟，重在分享，避免后来人再慢慢的研究，熬夜。

点睛之笔：

• 用一个 ExpandableListView ，在其 Child 布局中设置好功能布局，事先隐藏，当我点击右侧的更多按钮时，在显示出来。
• 事实证明这是多么正确，省事，省时的思想，哈哈。

靓照：

• 
• 
  

详细步骤：

这里就已上面第二张图为例吧，PlayList（播放列表）

功能描述：

• 点击播放列表时，出现该列表下的所有歌曲
• 每一首歌曲都可以点击右侧的“更多”按钮，出现下面的功能菜单（有“喜欢”，“添加到”...的那一个）

NO.1 主布局文件

playlist_fragment.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:orientation="vertical"    android:layout_width="match_parent"    android:layout_height="match_parent"     android:background="#191c1f"    xmlns:tools="http://schemas.android.com/tools" >        <ExpandableListView    android:id="@+id/playlist_list"    android:layout_width="match_parent"    android:layout_height="wrap_content"    android:cacheColorHint="#00000000"    android:childDivider="#00000000"    android:dividerHeight="1dp"    android:groupIndicator="@null"    android:fastScrollEnabled="true"/></LinearLayout>

NO.2  ExpandableListView的父布局文件

playlist_listitem_parent.xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="40dp"    android:background="@drawable/playlist_listitem_selector"    tools:ignore="HardcodedText" ><TextView    android:id="@+id/playlist_parent_text"    android:layout_width="match_parent"    android:layout_height="40dp"    android:paddingLeft="3dp"    android:gravity="left|center_vertical"    android:layout_gravity="left|center_vertical"    android:text="M"    android:textColor="@color/whitesmoke"    android:textSize="15sp"    android:textStyle="bold"    tools:ignore="HardcodedText" /></LinearLayout>

NO.3  ExpandableListView的子布局文件

default_listitem_child.xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="50dp"android:orientation="vertical"android:background="#00000000"android:paddingLeft="3dp"    tools:ignore="HardcodedText" >    <LinearLayout        android:layout_width="match_parent"    android:layout_height="wrap_content"    android:orientation="horizontal"    android:background="@drawable/default_listitem_selector"android:paddingLeft="10dp"android:paddingTop="10dp"android:paddingBottom="10dp">    <LinearLayout        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:orientation="vertical" >        <TextView            android:id="@+id/default_music_name"            android:layout_width="match_parent"            android:layout_height="wrap_content"            android:layout_weight="1"            android:text="大城小爱"            android:textSize="15sp"            android:textStyle="bold"            android:gravity="center_vertical|left"            android:textColor="@color/whitesmoke" />                <TextView            android:id="@+id/default_singer_name"            android:layout_width="match_parent"            android:layout_height="wrap_content"            android:layout_weight="1"            android:text="王力宏"            android:textSize="12sp"            android:gravity="center_vertical|left"            android:textColor="#8d8d8d" />    </LinearLayout>    <View android:layout_height="match_parent" android:layout_width="0dp" android:layout_weight="1"/>    <ImageView        android:id="@+id/default_more"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_gravity="right|center_vertical"        android:contentDescription="rightbtn"        android:scaleType="fitCenter"        android:focusable="false"        android:clickable="true"        android:src="@drawable/default_item_more_selector"/>    </LinearLayout><LinearLayout    android:id="@+id/settings_layout"android:layout_width="match_parent"  android:layout_height="wrap_content"  android:visibility="gone"  android:background="@color/black"  android:orientation="horizontal">    <TextView        android:drawableTop="@drawable/settings_love_selector"android:layout_width="wrap_content"  android:layout_height="wrap_content"  android:layout_weight="1"  android:clickable="true"  android:focusable="false"  android:textColor="@color/whitesmoke"  android:gravity="center"  android:text="喜欢"/>    <TextView        android:layout_marginLeft="10dp"        android:drawableTop="@drawable/settings_add_selector"android:layout_width="wrap_content"  android:layout_height="wrap_content"  android:clickable="true"  android:focusable="false"  android:layout_weight="1"  android:textColor="@color/whitesmoke"  android:gravity="center"  android:text="添加到"/>    <TextView        android:layout_marginLeft="10dp"        android:drawableTop="@drawable/settings_del_selector"android:layout_width="wrap_content"  android:layout_height="wrap_content"  android:layout_weight="1"  android:clickable="true"  android:focusable="false"  android:textColor="@color/whitesmoke"  android:gravity="center"  android:text="删除"/>    <TextView        android:layout_marginLeft="10dp"        android:drawableTop="@drawable/settings_info_selector"android:layout_width="wrap_content"  android:layout_height="wrap_content"  android:layout_weight="1"  android:textColor="@color/whitesmoke"  android:clickable="true"  android:focusable="false"  android:gravity="center"  android:text="信息"/>    <TextView        android:layout_marginLeft="10dp"        android:drawableTop="@drawable/settings_set_selector"android:layout_width="wrap_content"  android:layout_height="wrap_content"  android:layout_weight="1"  android:textColor="@color/whitesmoke"  android:gravity="center"  android:clickable="true"  android:focusable="false"  android:text="设置"/></LinearLayout></LinearLayout>

NO.4  自定义BaseExpandableListAdapter

package com.supermusic.adapter;import java.util.ArrayList;import java.util.HashMap;import com.supermusic.R;import com.supermusic.util.Music;import android.content.Context;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.view.View.OnClickListener;import android.widget.BaseExpandableListAdapter;import android.widget.ImageView;import android.widget.LinearLayout;import android.widget.TextView;@SuppressWarnings("unchecked")public class Playlist_ExListAdapter extends BaseExpandableListAdapter {private Context context=null;private ArrayList<HashMap<String,Object>>allData=null;public Playlist_ExListAdapter(Context context, ArrayList<HashMap<String,Object>>allData){this.context=context;this.allData=allData;}@Overridepublic int getGroupCount() {// 返回组的数量return allData.size();}@Overridepublic int getChildrenCount(int groupPosition) {// 返回指定组的 Child 数量HashMap<String,Object>oneData=(HashMap<String,Object>)allData.get(groupPosition);ArrayList<Music>childData=(ArrayList<Music>)oneData.get("childData");return childData.size();}@Overridepublic Object getGroup(int groupPosition) {// 返回指定组的数据HashMap<String,Object>oneData=(HashMap<String,Object>)allData.get(groupPosition);String parentData=(String)oneData.get("parentData");return parentData;}@Overridepublic Object getChild(int groupPosition, int childPosition) {// 返回指定组之指定 Child 的数据HashMap<String,Object>oneData=(HashMap<String,Object>)allData.get(groupPosition);ArrayList<Music>childData=(ArrayList<Music>)oneData.get("childData");return childData.get(childPosition);}@Overridepublic long getGroupId(int groupPosition) {// 返回指定组的IDreturn groupPosition;}@Overridepublic long getChildId(int groupPosition, int childPosition) {// 返回指定组之指定 Child 的IDreturn childPosition;}@Overridepublic boolean hasStableIds() {// 组以及 Child 的ID是否是固定不变的？return false;}@Overridepublic View getGroupView(int groupPosition, boolean isExpanded,View convertView, ViewGroup parent) {// 返回组的布局convertView=LayoutInflater.from(context).inflate(R.layout.playlist_listitem_parent, null);HashMap<String,Object>oneData=(HashMap<String,Object>)allData.get(groupPosition);String parentData=(String)oneData.get("parentData");TextView textview=(TextView)convertView.findViewById(R.id.playlist_parent_text);textview.setText(parentData);return convertView;}@Overridepublic View getChildView(int groupPosition, final int childPosition,boolean isLastChild, View convertView, ViewGroup parent) {// 返回 Child 的布局convertView=LayoutInflater.from(context).inflate(R.layout.default_listitem_child, null);HashMap<String,Object>oneData=(HashMap<String,Object>)allData.get(groupPosition);ArrayList<Music>childData=(ArrayList<Music>)oneData.get("childData");Music music = childData.get(childPosition);TextView music_name=(TextView)convertView.findViewById(R.id.default_music_name);TextView singer_name=(TextView)convertView.findViewById(R.id.default_singer_name);ImageView btn_more=(ImageView)convertView.findViewById(R.id.default_more);final LinearLayout settings_layout=(LinearLayout)convertView.findViewById(R.id.settings_layout);music_name.setText(music.music_name);singer_name.setText(music.singer_name);btn_more.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View v) {settings_layout.setVisibility(settings_layout.getVisibility()==View.GONE ? View.VISIBLE : View.GONE );}});return convertView;}@Overridepublic boolean isChildSelectable(int groupPosition, int childPosition) {// 指定的 Child 是否是可选择的return true;}}

NO.5  绑定数据

ExpandableListView listview=(ExpandableListView)view.findViewById(R.id.playlist_list);ArrayList<HashMap<String,Object>>allData = new ArrayList<HashMap<String,Object>>();//所有数据HashMap<String,Object>oneData = new HashMap<String,Object>();ArrayList<Music>childData= new ArrayList<Music>();//模拟数据 startoneData = new HashMap<String,Object>();childData= new ArrayList<Music>();oneData.put("parentData", "夜的钢琴曲");for(int j=0;j<4;j++){Music music=new Music();music.music_name="夜的钢琴曲第"+String.valueOf(j)+"首";music.singer_name="石进";childData.add(music);}oneData.put("childData", childData);allData.add(oneData);for(int i=1;i<7;i++){oneData = new HashMap<String,Object>();childData= new ArrayList<Music>();oneData.put("parentData", "playlist:"+String.valueOf(i));for(int j=0;j<4;j++){Music music=new Music();music.music_name="music:"+String.valueOf(j);music.singer_name="singer:"+String.valueOf(j);childData.add(music);}oneData.put("childData", childData);allData.add(oneData);}//模拟数据 endPlaylist_ExListAdapter adapter =new Playlist_ExListAdapter(getActivity(),allData);listview.setAdapter(adapter);for (int i = 0; i < adapter.getGroupCount(); i++)//关闭所有listview.collapseGroup(i);//listview.collapseGroup(i);//展开所有

/**************************************************************************************************

 *  本博客为CSDN博主【MK】原创，博客地址：http://blog.csdn.net/mkrcpp/article/details/13170649

 **********************************************************************************************************************/