Use of listview

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 Package  Com. Yarin. Android. examples_04_04;  Import  Android. App. activity;  Import  Android. database. cursor;  Import  Android. Graphics. color;  Import  Android. OS. Bundle;  Import  Android. provider. contactscontract; Import  Android. provider. contactscontract. phonelookup;  Import  Android. View. view;  Import  Android. widget. adapterview;  Import  Android. widget. linearlayout;  Import  Android. widget. listadapter;  Import  Android. widget. listview;  Import  Android. widget. simplecursoradapter; Import  Android. widget. Toast;  Public   Class Activity01 Extends  Activity {linearlayout m_linearlayout; listview m_listview;  /**  Called when the activity is first created.  */  @ Override  Public   Void  Oncreate (bundle savedinstancestate ){  Super . Oncreate (savedinstancestate );  /*  Create a linearlayout layout object  */  M_linearlayout = New Linearlayout ( This  );  /*  Set the properties of the layout linearlayout  */  M_linearlayout.setorientation (linearlayout. Vertical); m_linearlayout.setbackgroundcolor (Android. Graphics. color. Black );  /* Create a listview object  */  M_listview = New Listview ( This  ); Linearlayout. layoutparams Param = New  Linearlayout. layoutparams (linearlayout. layoutparams. fill_parent, linearlayout. layoutparams. wrap_content); m_listview.setbackgroundcolor (color. Black );  /*  Add m_listview to m_linearlayout Layout  */ M_linearlayout.addview (m_listview, Param );  /*  Set the display m_linearlayout Layout  */  Setcontentview (m_linearlayout );  //  Obtain the database phones cursor Cursor cur = getcontentresolver (). Query (contactscontract. Contacts. content_uri, Null , Null , Null , Null  ); Startmanagingcursor (cur ); //  Listadapter is a bridge between listview and background data Listadapter adapter = New Simplecursoradapter ( This  ,  //  Define a display template for each row in the list  //  Indicates that each row contains two data items.  Android. R. layout. simple_list_item_2,  //  Database cursor object  Cur,  // Retrieve data from the name and number columns of the database  //  New String [] {phonelookup. display_name, phonelookup. Number}              New  String [] {phonelookup. display_name, phonelookup. _ id },  //  Views corresponding to name and number              New   Int  [] {Android. R. Id. text1, Android. R. Id. text2 });  /*  Add the adapter to m_listview  */ M_listview.setadapter (adapter );  /*  Add a setonitemselectedlistener listener to the m_listview View  */  M_listview.setonitemselectedlistener (  New  Adapterview. onitemselectedlistener () {@ override  Public   Void Onitemselected (adapterview <?> Arg0, view arg1, Int Arg2, Long  Arg3) {displaytoast ( "Scroll to" + long. tostring (arg0.getselecteditemid () + "item" ) ;}@ Override  Public   Void Onnothingselected (adapterview <?> Arg0 ){  //  Not selected  }});  /*  Add a setonitemclicklistener listener to the m_listview View  */  M_listview.setonitemclicklistener (  New Adapterview. onitemclicklistener () {@ override  Public   Void Onitemclick (adapterview <?> Arg0, view arg1, Int Arg2, Long  Arg3 ){  //  To process the selected items Displaytoast ("selected" + integer. tostring (arg2 + 1) + "item" );}});}  /*  Show toast  */     Public   Void  Displaytoast (string Str) {toast. maketext (  This  , STR, Toast. length_short). Show ();}} 

The commented-out code is incorrect. I used the ID code to call the phone number to facilitate testing.

The usage of listview, especially the setonitemselectedlistener and setonitemclicklistener events, may be confusing to some children's shoes.

setonitemclicklistener -- this event is triggered when a row in the list is clicked. Items, such as touch screen clicks and buttons.
setonitemselectedlistener: this parameter is triggered only after you click (trackball or confirmation key), and setonitemclicklistener triggers the setonitemselectedlistener after the selected object is changed.
to trigger an event by clicking a row in the list, we recommend that you use the setonitemclicklistener event.