Android组件学习之ExpandableListView

一个简单的小例子:

Android组件学习之ExpandableListView

可以展开的ListView,和Listview差不多,只是设置的Adapter不同。常用的Adapter有BaseExpandableListAdapter、SimpleExpandableListAdapter、SimpleCursorTreeAdapter

布局如下:(布局中我设置了android:groupIndicator,不知道为什么不起作用。另外,android:dividerHeight这个属性是组对象和子节点共用的。如果要定义比较复杂的组视图及子节点视图,还是单独设置一个layout文件,再在Adapter中设置相应的返回View视图)

 1 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     xmlns:tools="http://schemas.android.com/tools"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:paddingBottom="@dimen/activity_vertical_margin"
 6     android:paddingLeft="@dimen/activity_horizontal_margin"
 7     android:paddingRight="@dimen/activity_horizontal_margin"
 8     android:paddingTop="@dimen/activity_vertical_margin"
 9     tools:context="com.example.testandroid.ui.MainActivity" >
10 
11     <ExpandableListView
12         android:id="@+id/main_elv1"
13         android:layout_width="match_parent"
14         android:layout_height="wrap_content"
15         android:layout_alignParentLeft="true"
16         android:layout_alignParentTop="true"
17         android:childDivider="@color/white"
18         android:divider="@color/gray"
19         android:dividerHeight="1px"
20         android:groupIndicator="@drawable/arrow_triangle_down"
21         android:indicatorLeft="4dp"
22         android:indicatorRight="4dp" >
23     </ExpandableListView>
24 
25 </RelativeLayout>

主Activity如下:

 1 package com.example.testandroid.ui;
 2 
 3 import android.os.Bundle;
 4 import android.support.v7.app.ActionBarActivity;
 5 import android.view.Menu;
 6 import android.view.MenuItem;
 7 import android.widget.ExpandableListView;
 8 
 9 import com.example.testandroid.R;
10 import com.example.testandroid.adapter.MainActivityExLVAdapter;
11 
12 public class MainActivity extends ActionBarActivity {
13 
14     private ExpandableListView mExpandableListView = null;
15     private MainActivityExLVAdapter mMainActivityExLVAdapter = null;
16 
17     @Override
18     protected void onCreate(Bundle savedInstanceState) {
19         super.onCreate(savedInstanceState);
20         setContentView(R.layout.activity_main);
21         init();
22     }
23 
24     private void init() {
25         mExpandableListView = (ExpandableListView) findViewById(R.id.main_elv1);
26         mMainActivityExLVAdapter = new MainActivityExLVAdapter(this);
27         mExpandableListView.setAdapter(mMainActivityExLVAdapter);
28     }
29 
30     @Override
31     public boolean onCreateOptionsMenu(Menu menu) {
32         getMenuInflater().inflate(R.menu.main, menu);
33         return true;
34     }
35 
36     @Override
37     public boolean onOptionsItemSelected(MenuItem item) {
38         int id = item.getItemId();
39         if (id == R.id.action_settings) {
40             return true;
41         }
42         return super.onOptionsItemSelected(item);
43     }
44 }

Adapter我写到另外一个类文件中:

  1 package com.example.testandroid.adapter;
  2 
  3 import android.content.Context;
  4 import android.view.View;
  5 import android.view.ViewGroup;
  6 import android.widget.BaseExpandableListAdapter;
  7 import android.widget.TextView;
  8 
  9 public class MainActivityExLVAdapter extends BaseExpandableListAdapter {
 10 
 11     private Context mContext = null;
 12 
 13     private String[] mGroup = { "FirstOne", "SecondTwo", "ThirdThress" };
 14     private String[][] mChildren = {
 15             { "2014-year-01-month-01", "2014-year-01-month-02",
 16                     "2014-year-01-month-03", "2014-year-01-month-04",
 17                     "2014-year-01-month-05" },
 18             { "2014-year-02-month-01", "2014-year-02-month-02",
 19                     "2014-year-02-month-03", "2014-year-02-month-04" },
 20             { "2014-year-03-month-01", "2014-year-03-month-02", } };
 21 
 22     public MainActivityExLVAdapter(Context mContext) {
 23         this.mContext = mContext;
 24     }
 25 
 26     /**
 27      * 获取组的数量
 28      */
 29     @Override
 30     public int getGroupCount() {
 31         return mGroup.length;
 32     }
 33 
 34     /**
 35      * 获取组下的节点数量
 36      */
 37     @Override
 38     public int getChildrenCount(int groupPosition) {
 39         return mChildren[groupPosition].length;
 40     }
 41 
 42     /**
 43      * 获取组对象(这个方法可以返回任意对象,或者null都行,给自己调用的)
 44      */
 45     @Override
 46     public Object getGroup(int groupPosition) {
 47         return mGroup[groupPosition];
 48     }
 49 
 50     /**
 51      * 获取子节点对象(这个方法可以返回任意对象,或者null都行,给自己调用的)
 52      */
 53     @Override
 54     public Object getChild(int groupPosition, int childPosition) {
 55         return mChildren[groupPosition][childPosition];
 56     }
 57 
 58     /**
 59      * 给自己调用的
 60      */
 61     @Override
 62     public long getGroupId(int groupPosition) {
 63         return groupPosition;
 64     }
 65 
 66     /**
 67      * 给自己调用的
 68      */
 69     @Override
 70     public long getChildId(int groupPosition, int childPosition) {
 71         return childPosition;
 72     }
 73 
 74     /**
 75      * TODO 不知道有什么用
 76      */
 77     @Override
 78     public boolean hasStableIds() {
 79         return true;
 80     }
 81 
 82     /**
 83      * 返回组对象的视图
 84      */
 85     @Override
 86     public View getGroupView(int groupPosition, boolean isExpanded,
 87             View convertView, ViewGroup parent) {
 88         TextView mTextView = new TextView(mContext);
 89         mTextView.setText(getGroup(groupPosition).toString());
 90         return mTextView;
 91     }
 92 
 93     /**
 94      * 返回子节点的视图
 95      */
 96     @Override
 97     public View getChildView(int groupPosition, int childPosition,
 98             boolean isLastChild, View convertView, ViewGroup parent) {
 99         TextView mTextView = new TextView(mContext);
100         mTextView.setText(getChild(groupPosition, childPosition).toString());
101         return mTextView;
102     }
103 
104     @Override
105     public boolean isChildSelectable(int groupPosition, int childPosition) {
106         return false;
107     }
108 
109 }

 

Android组件学习之ExpandableListView,布布扣,bubuko.com

Android组件学习之ExpandableListView

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