22.Android之ExpandableListView树形列表学习

时间：2016-01-05 22:17:11 阅读：343 评论：0 收藏：0 [点我收藏+]

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Android经常用到树形菜单，一般ExpandableListView可以满足这个需要，今天学习下。

XML代码：

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:orientation="vertical" >
 6 
 7     <LinearLayout
 8         android:layout_width="match_parent"
 9         android:layout_height="wrap_content" >
10 
11         <Button
12             android:id="@+id/btn_tree"
13             android:layout_width="wrap_content"
14             android:layout_height="wrap_content"
15             android:layout_weight="1"
16             android:text="两层结构" />
17 
18      
19         <Button
20             android:id="@+id/btn_supertree"
21             android:layout_width="wrap_content"
22             android:layout_height="wrap_content"
23             android:layout_weight="1"
24             android:text="三层结构" />
25 
26     </LinearLayout>
27 
28     <ExpandableListView
29         android:id="@+id/expandlist1"
30         android:layout_width="match_parent"
31         android:layout_height="wrap_content" >
32     </ExpandableListView>
33 
34 </LinearLayout>

接下来增加两个类TreeViewAdapter，SuperTreeViewAdaper继承BaseExpandableListAdapter，实现两层结构和三层结构效果：

TreeViewAdapter代码：

  1 package com.example.expandlistdemo;
  2 
  3 import java.util.ArrayList;
  4 import java.util.List;
  5 import android.content.Context;
  6 import android.util.Log;
  7 import android.view.Gravity;
  8 import android.view.View;
  9 import android.view.ViewGroup;
 10 import android.widget.AbsListView;
 11 import android.widget.BaseExpandableListAdapter;
 12 import android.widget.TextView;
 13 
 14 public class TreeViewAdapter extends BaseExpandableListAdapter {
 15 
 16     public static final int ItemHeight = 48;
 17     public static final int PaddingLeft = 36;
 18     private int myPaddingLeft = 0;
 19 
 20     static public class TreeNode {
 21         Object parent;
 22         List childs = new ArrayList();
 23     }
 24 
 25     List<TreeNode> treeNodes = new ArrayList<TreeNode>();
 26     Context parentContext;
 27 
 28     public TreeViewAdapter(Context view, int myPaddingLeft) {
 29         parentContext = view;
 30         this.myPaddingLeft = myPaddingLeft;
 31     }
 32 
 33     public List<TreeNode> GetTreeNode() {
 34         return treeNodes;
 35     }
 36 
 37     public void UpdateTreeNode(List<TreeNode> nodes) {
 38         treeNodes = nodes;
 39     }
 40 
 41     public void RemoveAll() {
 42         treeNodes.clear();
 43     }
 44 
 45     public Object getChild(int groupPosition, int childPosition) {
 46         return treeNodes.get(groupPosition).childs.get(childPosition);
 47     }
 48 
 49     public int getChildrenCount(int groupPosition) {
 50         return treeNodes.get(groupPosition).childs.size();
 51     }
 52 
 53     static public TextView getTextView(Context context) {
 54         AbsListView.LayoutParams lp = new AbsListView.LayoutParams(
 55                 ViewGroup.LayoutParams.FILL_PARENT, ItemHeight);
 56 
 57         TextView textView = new TextView(context);
 58         textView.setLayoutParams(lp);
 59         textView.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);
 60         return textView;
 61     }
 62 
 63     public View getChildView(int groupPosition, int childPosition,
 64             boolean isLastChild, View convertView, ViewGroup parent) {
 65         TextView textView = getTextView(this.parentContext);
 66         textView.setText(getChild(groupPosition, childPosition).toString());
 67         textView.setPadding(myPaddingLeft + PaddingLeft, 0, 0, 0);
 68         return textView;
 69     }
 70 
 71     public View getGroupView(int groupPosition, boolean isExpanded,
 72             View convertView, ViewGroup parent) {
 73         TextView textView = getTextView(this.parentContext);
 74         textView.setText(getGroup(groupPosition).toString());
 75         textView.setPadding(myPaddingLeft + (PaddingLeft >> 1), 0, 0, 0);
 76         return textView;
 77     }
 78 
 79     public long getChildId(int groupPosition, int childPosition) {
 80         return childPosition;
 81     }
 82 
 83     public Object getGroup(int groupPosition) {
 84         return treeNodes.get(groupPosition).parent;
 85     }
 86 
 87     public int getGroupCount() {
 88         return treeNodes.size();
 89     }
 90 
 91     public long getGroupId(int groupPosition) {
 92         return groupPosition;
 93     }
 94 
 95     public boolean isChildSelectable(int groupPosition, int childPosition) {
 96         return true;
 97     }
 98 
 99     public boolean hasStableIds() {
100         return true;
101     }
102 
103 }

SuperTreeViewAdaper代码：

  1 package com.example.expandlistdemo;
  2 
  3 import java.util.ArrayList;
  4 import java.util.List;
  5 import com.example.expandlistdemo.TreeViewAdapter.TreeNode;
  6 import android.content.Context;
  7 import android.view.View;
  8 import android.view.ViewGroup;
  9 import android.widget.AbsListView;
 10 import android.widget.BaseExpandableListAdapter;
 11 import android.widget.ExpandableListView;
 12 import android.widget.ExpandableListView.OnChildClickListener;
 13 import android.widget.ExpandableListView.OnGroupCollapseListener;
 14 import android.widget.ExpandableListView.OnGroupExpandListener;
 15 import android.widget.TextView;
 16 
 17 public class SuperTreeViewAdaper extends BaseExpandableListAdapter {
 18 
 19     static public class SuperTreeNode {
 20         Object parent;
 21         // 二级树形菜单的结构体
 22         List<TreeNode> childs = new ArrayList<TreeNode>();
 23     }
 24 
 25     private List<SuperTreeNode> superTreeNodes = new ArrayList<SuperTreeNode>();
 26     private Context parentContext;
 27     private OnChildClickListener stvClickEvent;// 外部回调函数
 28 
 29     public SuperTreeViewAdaper(Context view, OnChildClickListener stvClickEvent) {
 30         parentContext = view;
 31         this.stvClickEvent = stvClickEvent;
 32     }
 33 
 34     public List<SuperTreeNode> GetTreeNode() {
 35         return superTreeNodes;
 36     }
 37 
 38     public void UpdateTreeNode(List<SuperTreeNode> node) {
 39         superTreeNodes = node;
 40     }
 41 
 42     public void RemoveAll() {
 43         superTreeNodes.clear();
 44     }
 45 
 46     public Object getChild(int groupPosition, int childPosition) {
 47         return superTreeNodes.get(groupPosition).childs.get(childPosition);
 48     }
 49 
 50     public int getChildrenCount(int groupPosition) {
 51         return superTreeNodes.get(groupPosition).childs.size();
 52     }
 53 
 54     public ExpandableListView getExpandableListView() {
 55         AbsListView.LayoutParams lp = new AbsListView.LayoutParams(
 56                 ViewGroup.LayoutParams.FILL_PARENT, TreeViewAdapter.ItemHeight);
 57         ExpandableListView superTreeView = new ExpandableListView(parentContext);
 58         superTreeView.setLayoutParams(lp);
 59         return superTreeView;
 60     }
 61 
 62     /**
 63      * 三层树结构中的第二层是一个ExpandableListView
 64      */
 65     public View getChildView(int groupPosition, int childPosition,
 66             boolean isLastChild, View convertView, ViewGroup parent) {
 67         // 是
 68         final ExpandableListView treeView = getExpandableListView();
 69         final TreeViewAdapter treeViewAdapter = new TreeViewAdapter(
 70                 this.parentContext, 0);
 71         List<TreeNode> tmp = treeViewAdapter.GetTreeNode();// 临时变量取得TreeViewAdapter的TreeNode集合，可为空
 72         final TreeNode treeNode = (TreeNode) getChild(groupPosition,
 73                 childPosition);
 74         tmp.add(treeNode);
 75         treeViewAdapter.UpdateTreeNode(tmp);
 76         treeView.setAdapter(treeViewAdapter);
 77 
 78         // 关键点：取得选中的二级树形菜单的父子节点,结果返回给外部回调函数
 79         treeView.setOnChildClickListener(this.stvClickEvent);
 80 
 81         /**
 82          * 关键点：第二级菜单展开时通过取得节点数来设置第三级菜单的大小
 83          */
 84         treeView.setOnGroupExpandListener(new OnGroupExpandListener() {
 85             @Override
 86             public void onGroupExpand(int groupPosition) {
 87 
 88                 AbsListView.LayoutParams lp = new AbsListView.LayoutParams(
 89                         ViewGroup.LayoutParams.FILL_PARENT, (treeNode.childs
 90                                 .size() + 1) * TreeViewAdapter.ItemHeight + 10);
 91                 treeView.setLayoutParams(lp);
 92             }
 93         });
 94 
 95         /**
 96          * 第二级菜单回收时设置为标准Item大小
 97          */
 98         treeView.setOnGroupCollapseListener(new OnGroupCollapseListener() {
 99             @Override
100             public void onGroupCollapse(int groupPosition) {
101 
102                 AbsListView.LayoutParams lp = new AbsListView.LayoutParams(
103                         ViewGroup.LayoutParams.FILL_PARENT,
104                         TreeViewAdapter.ItemHeight);
105                 treeView.setLayoutParams(lp);
106             }
107         });
108         treeView.setPadding(TreeViewAdapter.PaddingLeft, 0, 0, 0);
109         return treeView;
110     }
111 
112     /**
113      * 三级树结构中的首层是TextView,用于作为title
114      */
115     public View getGroupView(int groupPosition, boolean isExpanded,
116             View convertView, ViewGroup parent) {
117         TextView textView = TreeViewAdapter.getTextView(this.parentContext);
118         textView.setText(getGroup(groupPosition).toString());
119         textView.setPadding(TreeViewAdapter.PaddingLeft, 0, 0, 0);
120         return textView;
121     }
122 
123     public long getChildId(int groupPosition, int childPosition) {
124         return childPosition;
125     }
126 
127     public Object getGroup(int groupPosition) {
128         return superTreeNodes.get(groupPosition).parent;
129     }
130 
131     public int getGroupCount() {
132         return superTreeNodes.size();
133     }
134 
135     public long getGroupId(int groupPosition) {
136         return groupPosition;
137     }
138 
139     public boolean isChildSelectable(int groupPosition, int childPosition) {
140         return true;
141     }
142 
143     public boolean hasStableIds() {
144         return true;
145     }
146 }

修改下MainActivity.java：

  1 package com.example.expandlistdemo;
  2 
  3 import java.util.List;
  4 
  5 import android.app.Activity;
  6 import android.os.Bundle;
  7 import android.view.View;
  8 import android.widget.Button;
  9 import android.widget.ExpandableListView;
 10 import android.widget.ExpandableListView.OnChildClickListener;
 11 import android.widget.Toast;
 12 
 13 public class MainActivity extends Activity {
 14 
 15     private Button btnTree;
 16     private Button btnSuperTree;
 17     private ExpandableListView expandlist;
 18     private TreeViewAdapter adapter;
 19     private SuperTreeViewAdaper superAdapter;
 20 
 21     public String[] groupTree = { "老师", "学生", "朋友" };
 22     public String[][] child = { { "王老师", "陈老师", "李老师", "黄老师" },
 23             { "学生甲", "学生乙", "学生丙" }, { "朋友甲", "朋友丁" } };
 24 
 25     public String[] parent = { "老师", "学生" };
 26     public String[][][] child_grandson = { { { "王老师" }, { "AA", "AAA" } },
 27             { { "陈老师" }, { "BBB", "BBBB", "BBBBB" } },
 28             { { "李老师" }, { "CCC", "CCCC" } },
 29             { { "黄老师" }, { "DDD", "DDDD", "DDDDD" } } };
 30 
 31     /**
 32      * 三级树形菜单的事件不再可用，本函数由三级树形菜单的子项（二级菜单）进行回调
 33      */
 34     OnChildClickListener stvClickEvent = new OnChildClickListener() {
 35 
 36         @Override
 37         public boolean onChildClick(ExpandableListView parent, View v,
 38                 int groupPosition, int childPosition, long id) {
 39 
 40             String str = "parent id:" + String.valueOf(groupPosition)
 41                     + ",children id:" + String.valueOf(childPosition);
 42             Toast.makeText(getApplicationContext(), str, 300).show();
 43 
 44             return false;
 45 
 46         }
 47 
 48     };
 49     
 50     @Override
 51     protected void onCreate(Bundle savedInstanceState) {
 52         super.onCreate(savedInstanceState);
 53         setContentView(R.layout.activity_main);
 54 
 55         btnTree = (Button) findViewById(R.id.btn_tree);
 56         btnSuperTree = (Button) findViewById(R.id.btn_supertree);
 57 
 58         adapter = new TreeViewAdapter(this, TreeViewAdapter.PaddingLeft >> 1);
 59 
 60         superAdapter = new SuperTreeViewAdaper(this, stvClickEvent);
 61         expandlist = (ExpandableListView) findViewById(R.id.expandlist1);
 62 
 63         btnTree.setOnClickListener(new View.OnClickListener() {
 64 
 65             @Override
 66             public void onClick(View v) {
 67 
 68                 adapter.RemoveAll();
 69                 adapter.notifyDataSetChanged();
 70                 superAdapter.RemoveAll();
 71                 superAdapter.notifyDataSetChanged();
 72  
 73                 List treeNode = adapter.GetTreeNode();
 74                 for (int i = 0; i < groupTree.length; i++) {
 75                     TreeViewAdapter.TreeNode node = new TreeViewAdapter.TreeNode();
 76                     node.parent = groupTree[i];
 77                     for (int ii = 0; ii < child[i].length; ii++) {
 78                         node.childs.add(child[i][ii]);
 79                     }
 80                     treeNode.add(node);
 81                 }
 82 
 83                 adapter.UpdateTreeNode(treeNode);
 84                 expandlist.setAdapter(adapter);
 85                 expandlist.setOnChildClickListener(new OnChildClickListener() {
 86 
 87                     @Override
 88                     public boolean onChildClick(ExpandableListView arg0,
 89                             View arg1, int parent, int children, long arg4) {
 90 
 91                         String str = "parent id:" + String.valueOf(parent)
 92                                 + ",children id:" + String.valueOf(children);
 93                         Toast.makeText(getApplicationContext(), str, 300)
 94                                 .show();
 95                         return false;
 96                     }
 97                 });
 98 
 99             }
100         });
101 
102         btnSuperTree.setOnClickListener(new View.OnClickListener() {
103 
104             @Override
105             public void onClick(View v) {
106 
107                 adapter.RemoveAll();
108                 adapter.notifyDataSetChanged();
109                 superAdapter.RemoveAll();
110                 superAdapter.notifyDataSetChanged();
111 
112                 List superTreeNode = superAdapter.GetTreeNode();
113                 for (int i = 0; i < parent.length; i++) // 第一层
114                 {
115                     SuperTreeViewAdaper.SuperTreeNode superNode = new SuperTreeViewAdaper.SuperTreeNode();
116                     superNode.parent = parent[i];
117 
118                     // 第二层
119                     for (int ii = 0; ii < child_grandson.length; ii++) {
120                         TreeViewAdapter.TreeNode node = new TreeViewAdapter.TreeNode();
121                         node.parent = child_grandson[ii][0][0];// 第二级菜单的标题
122 
123                         for (int iii = 0; iii < child_grandson[ii][1].length; iii++) // 第三级菜单
124                         {
125                             node.childs.add(child_grandson[ii][1][iii]);
126                         }
127                         superNode.childs.add(node);
128                     }
129                     superTreeNode.add(superNode);
130 
131                 }
132                 superAdapter.UpdateTreeNode(superTreeNode);
133                 expandlist.setAdapter(superAdapter);
134             }
135 
136         });
137     }
138 }