java - How to list all events on list view with database? -

the program/apk need list titles , when run apk close please me dont know happens really

package com.eu.agendamarinhagrande;  import android.annotation.targetapi; import android.app.progressdialog; import android.content.intent; import android.os.asynctask; import android.os.build; import android.support.v7.app.actionbar; import android.support.v7.app.actionbaractivity; import android.os.bundle; import android.util.log; import android.view.menu; import android.view.menuitem; import android.view.view; import android.widget.adapterview; import android.widget.listadapter; import android.widget.listview; import android.widget.simpleadapter; import android.widget.textview;  import com.eu.agendamarinhagrande.jsonparser; import com.eu.agendamarinhagrande.r;  import org.apache.http.namevaluepair; import org.json.jsonarray; import org.json.jsonexception; import org.json.jsonobject;  import java.util.arraylist; import java.util.hashmap; import java.util.list;   public class mainactivity extends actionbaractivity {      // progress dialog     private progressdialog pdialog;      // creating json parser object     jsonparser jparser = new jsonparser();      arraylist<hashmap<string, string>> empresalist;       // url products list     private static string url_all_empresas = "http://www.grifin.pt/projectoamg/conexao.php";      // json node names       private static final string tag_titulo = "titulo";       // products jsonarray     string resultado = null;      listview lista;      @targetapi(build.version_codes.honeycomb)     @override     public void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.activity_main);          // hashmap para el listview         empresalist = new arraylist<hashmap<string, string>>(); loadallproducts loadallproducts = new loadallproducts();         // cargar los productos en el background thread          lista = (listview) findviewbyid(r.id.agenda); loadallproducts.execute(string.valueof(lista));         actionbar actionbar = getsupportactionbar();         actionbar.setdisplayhomeasupenabled(true);      }//fin oncreate       class loadallproducts extends asynctask<string, string, string> {          /**          * antes de empezar el background thread show progress dialog          */         @override         protected void onpreexecute() {             super.onpreexecute();             pdialog = new progressdialog(mainactivity.this);             pdialog.setmessage("a carregar eventos. por favor espere...");             pdialog.setindeterminate(false);             pdialog.setcancelable(false);             pdialog.show();         }          /**          * obteniendo todos los productos          */         protected string doinbackground(string... args) {             // building parameters             list params = new arraylist();             // getting json string url             jsonobject json = jparser.makehttprequest(url_all_empresas, "get", params); stringbuilder sb = new stringbuilder();             // check log cat json reponse             log.d("all products: ", url_all_empresas.tostring());            resultado = sb.tostring();             try {                 // checking success tag                  // products found                 // getting array of products                      jsonarray arrayjson = new jsonarray(resultado);                 (int = 0; i<arrayjson.length();i++){                    // storing each json item in variable                 jsonobject c = arrayjson.getjsonobject(i);                 string titulo = c.getstring(tag_titulo);                   // creating new hashmap                 hashmap map = new hashmap();                  // adding each child node hashmap key => value                 map.put(tag_titulo, titulo);                   empresalist.add(map);             }              } catch (jsonexception e) {                 e.printstacktrace();             }             return null;         }          protected void onpostexecute(string file_url) {             // dismiss dialog after getting products             pdialog.dismiss();             // updating ui background thread             runonuithread(new runnable() {                 public void run() {                     /**                      * updating parsed json data listview                      * */                     listadapter adapter = new simpleadapter(                             mainactivity.this,                             empresalist,                             r.layout.single_post,                             new string[]{                                     tag_titulo                              },                             new int[]{                                     r.id.single_post_tv_id                              });                     // updating listview                     //setlistadapter(adapter);                     lista.setadapter(adapter);                 }             });          }     } } 

check line in oncreate() method:

loadallproducts.execute(string.valueof(lista)); 

you can not string value of listview! if want value of textview in listview, add onitemclick event listview , value of textview in selected list item this:

//a variable, use methods, have value value of selected textview private string selectedvalue;  @override protected void onlistitemclick(listview l, view v, int position, long id) {      view view = (view)v.getparent();        textview textyouneed = (textview) view.findviewbyid(r.id.textviewid);      selectedvalue = textyouneed.gettext(); } 

and use variable in line told above:

loadallproducts.execute(selectedvalue);