Brief Introduction to Adapter in Android

The Adapter in Android is very useful for customizing the display list, such as SimpleAdapter. Its constructor is:
Public SimpleAdapter (Context context, List> data, int resource, String [] from, int [])
The meanings of its parameters:
1. context, context, SimpleAdapter associated view, which is generally the current Activity, this
2. data: generic List, such as ArrayList, Map, or HashMap
3. resource, resource file, an R. layout, is the layout to be displayed.
4. from, an array, key-value pairs in Map.
5. to, the unique int type identifier formed by the name id in the xml file of layout
For example:
Define a List in a ListActivity:
List> people = new ArrayList> ();
Map m = new HashMap ();
M. put ("name", "tom ");
M. put ("age", "20 ");
People. add (m );
...
SimpleAdapter adapter = new SimpleAdapter (this,
(List>) feets, R. layout. main,
New String [] {"name", "age"}, new int [] {R. id. name, R. id. age });
SetListAdapter (adapter );
Where:
R. id. name, R. id. age are two textviews defined in an XML layout file used to display name and age. The layout file must have a ListView. Or it can be defined in a program.
In addition, you do not need to set setContentView in ListActivity. The system is automatically loaded.