Android ExpandableListActivity 学习笔记

ExpandableListActivity:

   An activity that displays an expandable list of items by binding to a data source implementing the ExpandableListAdapter, and exposes event handlers when the user selects an item.

  即，可扩展的list，单击某个item后，又可显示一个子list。它的数据通过绑定到ExpandableListAdapter或者ExpandableListAdapter的子类上。

示例1—通过SimpelExpandableListAdapter绑定数据：

 

 

注意：android.R.layout.simple_expandable_list_item_1：表示只显示一个TextView的数据，即R.id.text1

          android.R.layout.simple_expandable_list_item_2：表示显示二个TextView的数据，即R.id.text1，R.id,text2

         android.R.layout.simple_expandable_list_item_2.xml(在R.layout中)文件的布局如下：

 

 

示例2—通过SimpleCussorTreeAdapter绑定数据：

 

 

 

示例3—通过BaseExpandableListAdapter绑定数据：

 

view plaincopy to clipboardprint?

1. public class ExpandableList1 extends ExpandableListActivity {  
2.   
3.     ExpandableListAdapter mAdapter;  
4.   
5.     @Override  
6.     public void onCreate(Bundle savedInstanceState) {  
7.         super.onCreate(savedInstanceState);  
8.   
9.         // Set up our adapter  
10.         mAdapter = new MyExpandableListAdapter();  
11.         setListAdapter(mAdapter);  
12.         // register context menu, when long click the item, it will show a dialog  
13.         registerForContextMenu(getExpandableListView());  
14.     }  
15.   
16.     @Override  
17.     public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) {  
18.         menu.setHeaderTitle("Sample menu");  
19.         menu.add(0, 0, 0, R.string.expandable_list_sample_action);  
20.     }  
21.       
22.     @Override  
23.     public boolean onContextItemSelected(MenuItem item) {  
24.         ExpandableListContextMenuInfo info = (ExpandableListContextMenuInfo) item.getMenuInfo();  
25.   
26.         String title = ((TextView) info.targetView).getText().toString();  
27.           
28.         int type = ExpandableListView.getPackedPositionType(info.packedPosition);  
29.         if (type == ExpandableListView.PACKED_POSITION_TYPE_CHILD) {  
30.             int groupPos = ExpandableListView.getPackedPositionGroup(info.packedPosition);   
31.             int childPos = ExpandableListView.getPackedPositionChild(info.packedPosition);   
32.             Toast.makeText(this, title + ": Child " + childPos + " clicked in group " + groupPos,  
33.                     Toast.LENGTH_SHORT).show();  
34.             return true;  
35.         } else if (type == ExpandableListView.PACKED_POSITION_TYPE_GROUP) {  
36.             int groupPos = ExpandableListView.getPackedPositionGroup(info.packedPosition);   
37.             Toast.makeText(this, title + ": Group " + groupPos + " clicked", Toast.LENGTH_SHORT).show();  
38.             return true;  
39.         }  
40.           
41.         return false;  
42.     }  
43.   
44.     /** 
45.      * A simple adapter which maintains an ArrayList of photo resource Ids.  
46.      * Each photo is displayed as an image. This adapter supports clearing the 
47.      * list of photos and adding a new photo. 
48.      * 
49.      */  
50.     public class MyExpandableListAdapter extends BaseExpandableListAdapter {  
51.         // Sample data set.  children[i] contains the children (String[]) for groups[i].  
52.         private String[] groups = { "People Names", "Dog Names", "Cat Names", "Fish Names" };  
53.         private String[][] children = {  
54.                 { "Arnold", "Barry", "Chuck", "David" },  
55.                 { "Ace", "Bandit", "Cha-Cha", "Deuce" },  
56.                 { "Fluffy", "Snuggles" },  
57.                 { "Goldy", "Bubbles" }  
58.         };  
59.           
60.         public Object getChild(int groupPosition, int childPosition) {  
61.             return children[groupPosition][childPosition];  
62.         }  
63.   
64.         public long getChildId(int groupPosition, int childPosition) {  
65.             return childPosition;  
66.         }  
67.   
68.         public int getChildrenCount(int groupPosition) {  
69.             return children[groupPosition].length;  
70.         }  
71.   
72.         public TextView getGenericView() {  
73.             // Layout parameters for the ExpandableListView  
74.             AbsListView.LayoutParams lp = new AbsListView.LayoutParams(  
75.                     ViewGroup.LayoutParams.FILL_PARENT, 64);  
76.   
77.             TextView textView = new TextView(ExpandableList1.this);  
78.             textView.setLayoutParams(lp);  
79.             // Center the text vertically  
80.             textView.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);  
81.             // Set the text starting position  
82.             textView.setPadding(36, 0, 0, 0);  
83.             return textView;  
84.         }  
85.           
86.         public View getChildView(int groupPosition, int childPosition, boolean isLastChild,  
87.                 View convertView, ViewGroup parent) {  
88.             TextView textView = getGenericView();  
89.             textView.setText(getChild(groupPosition, childPosition).toString());  
90.             return textView;  
91.         }  
92.   
93.         public Object getGroup(int groupPosition) {  
94.             return groups[groupPosition];  
95.         }  
96.   
97.         public int getGroupCount() {  
98.             return groups.length;  
99.         }  
100.   
101.         public long getGroupId(int groupPosition) {  
102.             return groupPosition;  
103.         }  
104.   
105.         public View getGroupView(int groupPosition, boolean isExpanded, View convertView,  
106.                 ViewGroup parent) {  
107.             TextView textView = getGenericView();  
108.             textView.setText(getGroup(groupPosition).toString());  
109.             return textView;  
110.         }  
111.   
112.         public boolean isChildSelectable(int groupPosition, int childPosition) {  
113.             return true;  
114.         }  
115.   
116.         public boolean hasStableIds() {  
117.             return true;  
118.         }  
119.   
120.     }  
121. }

view plaincopy to clipboardprint?

1. public class ExpandableList2 extends ExpandableListActivity {  
2.     private int mGroupIdColumnIndex;   
3.       
4.     private String mPhoneNumberProjection[] = new String[] {  
5.             People.Phones._ID, People.Phones.NUMBER  
6.     };  
7.   
8.       
9.     private ExpandableListAdapter mAdapter;  
10.       
11.         /*  
12.          * CursorTreeAdapter's method.  
13.          * Gets the Cursor for the children at the given group  
14.          * /  
15.     @Override  
16.     public void onCreate(Bundle savedInstanceState) {  
17.         super.onCreate(savedInstanceState);  
18.   
19.         // Query for people  
20.         Cursor groupCursor = managedQuery(People.CONTENT_URI,  
21.                 new String[] {People._ID, People.NAME}, null, null, null);  
22.   
23.         // Cache the ID column index  
24.         mGroupIdColumnIndex = groupCursor.getColumnIndexOrThrow(People._ID);  
25.   
26.         // Set up our adapter  
27.         mAdapter = new MyExpandableListAdapter(groupCursor,  
28.                 this,  
29.                 android.R.layout.simple_expandable_list_item_1,  
30.                 android.R.layout.simple_expandable_list_item_1,  
31.                 new String[] {People.NAME}, // Name for group layouts  
32.                 new int[] {android.R.id.text1},  
33.                 new String[] {People.NUMBER}, // Number for child layouts  
34.                 new int[] {android.R.id.text1});  
35.         setListAdapter(mAdapter);  
36.     }  
37.   
38.     public class MyExpandableListAdapter extends SimpleCursorTreeAdapter {  
39.   
40.         public MyExpandableListAdapter(Cursor cursor, Context context, int groupLayout,  
41.                 int childLayout, String[] groupFrom, int[] groupTo, String[] childrenFrom,  
42.                 int[] childrenTo) {  
43.             super(context, cursor, groupLayout, groupFrom, groupTo, childLayout, childrenFrom,  
44.                     childrenTo);  
45.         }  
46.   
47.   
48.         @Override  
49.         protected Cursor getChildrenCursor(Cursor groupCursor) {  
50.             // Given the group, we return a cursor for all the children within that group   
51.   
52.             // Return a cursor that points to this contact's phone numbers  
53.             Uri.Builder builder = People.CONTENT_URI.buildUpon();  
54.             ContentUris.appendId(builder, groupCursor.getLong(mGroupIdColumnIndex));  
55.             builder.appendEncodedPath(People.Phones.CONTENT_DIRECTORY);  
56.             Uri phoneNumbersUri = builder.build();  
57.   
58.             // The returned Cursor MUST be managed by us, so we use Activity's helper  
59.             // functionality to manage it for us.  
60.             return managedQuery(phoneNumbersUri, mPhoneNumberProjection, null, null, null);  
61.         }  
62.   
63.     }  
64. }  

view plaincopy to clipboardprint?

1. <?xml version="1.0" encoding="utf-8"?>  
2.  <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  
3.      android:layout_width="fill_parent"  
4.      android:layout_height="wrap_content"  
5.      android:orientation="vertical">  
6.    
7.      <TextView android:id="@+id/text1"  
8.          android:textSize="16sp"  
9.          android:textStyle="bold"  
10.          android:layout_width="fill_parent"  
11.          android:layout_height="wrap_content"/>  
12.    
13.      <TextView android:id="@+id/text2"  
14.          android:textSize="16sp"  
15.          android:layout_width="fill_parent"  
16.          android:layout_height="wrap_content"/>  
17.  </LinearLayout>  

view plaincopy to clipboardprint?

1. public class ExpandableList3 extends ExpandableListActivity {  
2.     private static final String NAME = "NAME";  
3.     private static final String IS_EVEN = "IS_EVEN";  
4.       
5.     private ExpandableListAdapter mAdapter;  
6.       
7.     @Override  
8.     public void onCreate(Bundle savedInstanceState) {  
9.         super.onCreate(savedInstanceState);  
10.   
11.         List<Map<String, String>> groupData = new ArrayList<Map<String, String>>();  
12.         List<List<Map<String, String>>> childData = new ArrayList<List<Map<String, String>>>();  
13.         for (int i = 0; i < 20; i++) {  
14.             Map<String, String> curGroupMap = new HashMap<String, String>();  
15.             groupData.add(curGroupMap);  
16.             curGroupMap.put(NAME, "Group " + i);  
17.             curGroupMap.put(IS_EVEN, (i % 2 == 0) ? "This group is even" : "This group is odd");  
18.               
19.             List<Map<String, String>> children = new ArrayList<Map<String, String>>();  
20.             for (int j = 0; j < 15; j++) {  
21.                 Map<String, String> curChildMap = new HashMap<String, String>();  
22.                 children.add(curChildMap);  
23.                 curChildMap.put(NAME, "Child " + j);  
24.                 curChildMap.put(IS_EVEN, (j % 2 == 0) ? "This child is even" : "This child is odd");  
25.             }  
26.             childData.add(children);  
27.         }  
28.           
29.         // Set up our adapter  
30.         mAdapter = new SimpleExpandableListAdapter(  
31.                 this,  
32.                 groupData,  // 存储父list的数据  
33.                 android.R.layout.simple_expandable_list_item_2, //父list的现实方式  
34.                 new String[] { NAME,IS_EVEN},                    // 父list需要显示的数据  
35.             new int[] { android.R.id.text1,android.R.id.text2}, // 父list的数据绑定到的view  
36.                 childData,                                      //子list的数据  
37.                 android.R.layout.simple_expandable_list_item_2,  
38.                 new String[] { NAME, IS_EVEN },  
39.                 new int[] { android.R.id.text1, android.R.id.text2 }  
40.                 );  
41.         setListAdapter(mAdapter);  
42.     }  
43.   
44. }