CheckBox and ListView

package com.example.selectall;import java.util.arraylist;import java.util.list;import  android.app.activity;import android.os.bundle;import android.view.view;import  android.view.view.onclicklistener;import android.widget.arrayadapter;import android.widget.checkbox; import android.widget.listview;import android.widget.spinner;import  android.widget.spinneradapter;import android.widget.textview;public class mainactivity  extends activity {    private listview listview;     private TextView tvCount;    private CheckBox checkAll;     private MyAdapter adapter;    private List<User>  datas;    private boolean isselectall;//Select All (Learn to play this)      private int selectcount;//statistics selected number of     @oVerride    protected void oncreate (bundle savedinstancestate)  {         super.oncreate (savedinstancestate);         setcontentview (R.layout.activity_main);         Initview ();         initdata ();         adapter = new myadapter (datas, this);         listview.setadapter (Adapter);         Checkall.setonclicklistener (New onclicklistener ()  {              @Override              Public void onclick (VIEW&NBSP;V)  {                 isselectall = ! isselectall;                // Update views with the Select All button                  Updateselectallstatus ();            }         });     }    private void  updateselectallstatus ()  {        for (User user:datas) {             user.setchecked (ISSELECTALL);         }        if  ( Isselectall)  {            selectcount =  datas.size ();        }else{             selectCount = 0;        }         tvcount.settext ("You have selected" +selectcount+ ");         adapter.notifydatasetchanged ();    }    private void  InitData ()  {        datas = new arraylist<user > ();        user user;         for (int i= 0;i<15;i++) {             user = new user ("name" +i,10+i);             datas.add (user);        }             }    private void initview ()  {        listview =  (ListView)  findviewbyid (R.id.listview);         tvCount =  (TextView)  findviewbyid (r.id.tvcount);         checkAll =  (CheckBox)  findviewbyid (r.id.checkall);     }    public void oprate (string oprate) {         if  ("Add". Equals (oprate))  {             selectcount++;        }else if ("Sub ". Equals (oprate)) {            selectcount--;         }                 if  (Selectcount==datas.size ())  {           &nBsp; checkall.setchecked (True);             isselectall = true;        }else{             checkall.setchecked (False);             isSelectAll = false;         }        tvcount.settext ("You have selected" +selectCount+ ");     }}

package com.example.selectall;import java.util.list;import android.content.context;import  Android.view.layoutinflater;import android.view.view;import android.view.view.onclicklistener;import  android.view.ViewGroup;import android.webkit.WebView.FindListener;import  Android.widget.baseadapter;import android.widget.checkbox;import android.widget.textview;public  class MyAdapter extends BaseAdapter {    private List< User> datas;    private context context;    public  myadapter ( list<user> datas,context context)  {         this.context = context;        this.datas  = datas;    }     @Override     public  int getcount () &NBSP;{&NBSP;&NBSP;&NBsp;     return datas.size ();     }    @ Override    public object getitem (int position)  {         return datas.get (position);    }      @Override     public long getitemid (int position)  {         return position;    }    @ Override    public view getview (Int position, view convertview,  viewgroup parent)  {        ViewHolder viewHolder;         if  (convertview==null)  {             convertview = layoutinflater.from (context). Inflate ( R.layout.item, null);              viewholder = new viewholder ( );            viewholder.tvname =  ( TextView)  convertview.findviewbyid (r.id.name);             viewHolder.tvage =  (TextView)  convertview.findviewbyid (r.id.age);             viewHolder.checkBox =  (CheckBox)   Convertview.findviewbyid (R.id.check);             / /set a tag   to fetch objects from the cache              Convertview.settag (Viewholder);        }else{             viewHolder =  (Viewholder)  convertview.gettag ();         }        final user user =  Datas.get (position);         viewholder.tvname.settext (User.getName ());         viewholder.tvage.settext (User.getage () + "");         viewholder.checkbox.setchecked (user.ischecked ());         viewholder.checkbox.setonclicklistener (New onclicklistener ()  {              @Override              public void onclick (VIEW&NBSP;V)  {                 boolean ischecked = ! User.ischecked ();                 user.setchecked (isChecked);                 if  (isChecked )  {                     //(Learn to play this)                       ((mainactivity) context). Oprate ("add");                 }else{                     //minus                       ( mainactivity). Oprate ("sub");                 }            }          });         return convertview;    }     class ViewHolder{        TextView  tvname,tvage;        checkbox checkbox;    }}

package com.example.selectall;public class user {    private  string name;    private int  age;    private  Boolean ischecked;    public user ()  {    }     public user (string name, int age)  {         this.name = name;        this.age =  Age;    }    public string getname ()  {         return name;    }    public  void setname (String name)  {        this.name  = name;    }    public int getage ()  {       &nBsp; return age;    }    public void setage (int  age)  {        this.age = age;     }    public boolean ischecked ()  {         return isChecked;    }    public void  Setchecked (boolean ischecked)  {        this.ischecked =  ischecked;    }    }

CheckBox and ListView