ListView paging data loading for Android

1. The effect is as follows:

The example is as follows: The add data button can be changed to a progress bar because there is no data, so I add a button to the database for testing. Generally, it takes some time to pull data from the server, so you can get a progress bar to prompt the user:

When you click the Load button, read the data from the database and append the read data to the original dataset.

Package com. exampleandroid. xiong. listviewpages; public class News {private String title; private int id;/***** @ return News title */public String getTitle () {return title ;} /***** @ param title * set the news title */public void setTtitle (String title) {this. title = title;}/***** @ return news id */public int getId () {return id ;} /***** @ param id * set the news id */public void setId (int id) {this. id = id ;}}

Package com. exampleandroid. xiong. listviewpages; import java. util. arrayList; import java. util. list; import android. database. cursor; import android. database. sqlite. SQLiteDatabase; public class GetNews {/***** @ param page * Number of pages to be loaded 5 records per page * @ param dbnews * SQLiteOpenHelper subclass * @ return returned news loaded data */public list
 
  
GetListNews (int page, DbSqliteNews dbnews) {List
  
   
List = new ArrayList
   
    
(); String SQL = "select * from tb_newstile where news_id not in (select news_id from tb_newstile LIMIT" + 5 * (page-1) + ") LIMIT" + 5 * page; cursor cursor = dbnews. getReadableDatabase (). rawQuery (SQL, null); while (cursor. moveToNext () {News news = new News (); news. setTtitle (cursor. getString (1); news. setId (cursor. getInt (0); list. add (news);} cursor. close (); return list;}/*** insert 100 pieces of data for testing ** @ param d Bnews * SQLiteOpenHelper subclass */public void insertData (DbSqliteNews dbnews) {SQLiteDatabase datas = dbnews. getWritableDatabase (); datas. beginTransaction (); try {for (int I = 0; I <100; I ++) Export datas.exe cSQL ("insert into tb_newstile values (?,?) ", New Object [] {I," news title "+ I});} datas. setTransactionSuccessful ();} catch (Exception e) {System. out. println ("data insertion failed! "); E. printStackTrace () ;}finally {datas. endTransaction ();}}}
   
  
 

Package com. exampleandroid. xiong. listviewpages; import android. content. context; import android. database. sqlite. SQLiteDatabase; import android. database. sqlite. SQLiteDatabase. cursorFactory; import android. database. sqlite. SQLiteOpenHelper; public class DbSqliteNews extends SQLiteOpenHelper {public DbSqliteNews (Context context, String name, CursorFactory factory, int version) {super (context, name, factory, version );} // create a database table @ Overridepublic void onCreate (SQLiteDatabase db) mongodb.exe cSQL ("create table tb_newstile (news_id integer, news_title varchar (100 ))");} @ Overridepublic void onUpgrade (SQLiteDatabase db, int oldVersion, int newVersion ){}}

Package com. exampleandroid. xiong. listviewpages; import java. util. list; import android. app. activity; import android. OS. bundle; import android. view. layoutInflater; import android. view. menu; import android. view. view; import android. view. view. onClickListener; import android. view. viewGroup; import android. widget. baseAdapter; import android. widget. button; import android. widget. imageView; import android. widget. listView; import android. widget. textView; public class MainActivity extends Activity {private ListView newShow_list; private Button loadmore, adddata; // private List of data loaded by ListView
 
  
Shownews; private GetNews getnews; private DbSqliteNews dbnews; // The number of loaded pages private int pagecount = 1; @ Overrideprotected void onCreate (Bundle savedInstanceState) {super. onCreate (savedInstanceState); setContentView (R. layout. activity_main); newShow_list = (ListView) findViewById (R. id. newsShow_list); loadmore = (Button) findViewById (R. id. loadmore_bt); adddata = (Button) findViewById (R. id. adddata); dbnews = new DbSqliteNews (this, "new. db ", null, 1); getnews = new GetNews (); final ListAdpaterNews listadpter = new ListAdpaterNews (); // This button only adds test data to adddata. setOnClickListener (new OnClickListener () {@ Overridepublic void onClick (View v) {// insert data getnews. insertData (dbnews); // obtain the data shownews = getnews. getListNews (pagecount, dbnews); // display data newShow_list.setAdapter (listadpter) ;}}); loadmore. setOnClickListener (new OnClickListener () {@ Overridepublic void onClick (View v) {pagecount ++; // append data to the original set shownews. addAll (getnews. getListNews (pagecount, dbnews); // refresh the data listadpter. notifyDataSetInvalidated () ;}}); // shownews = getnews. getListNews (pagecount, dbnews); newShow_list.setAdapter (listadpter);} class ListAdpaterNews extends BaseAdapter {@ Overridepublic int getCount () {return pagecount * 5;} @ Overridepublic Object getItem (position) {return position ;}@ Overridepublic long getItemId (int position) {return position ;}@ Overridepublic View getView (int position, View convertView, ViewGroup parent) {View view = LayoutInflater. from (MainActivity. this ). inflate (R. layout. news_title, null); TextView txttitle = (TextView) view.findViewById(R.id.txt _ title); ImageView images = (ImageView) view. findViewById (R. id. showimage_title); images. setBackgroundResource (R. drawable. n_me_l); txttitle. setText (shownews. get (position ). getTitle (); return view; }}@ Overridepublic boolean onCreateOptionsMenu (Menu menu) {getMenuInflater (). inflate (R. menu. main, menu); return true ;}}
 

Source code download: http://download.csdn.net/detail/x605940745/6800461

Reprinted please indicate the source: http://blog.csdn.net/x605940745