Make a ListView high efficiency universal Adapter

This case study from the _ Yang, the great God, I wrote it again, deepen the memory http://blog.csdn.net/lmj623565791/article/details/38902805

We used to write the ListView like this.

1  PackageCom.example.listviewdemo;2 3 Importjava.util.ArrayList;4 Importjava.util.List;5 6 Importandroid.app.Activity;7 ImportAndroid.os.Bundle;8 ImportAndroid.widget.ListView;9 Ten  Public classMainactivityextendsActivity { One  A     PrivateListView LV; -     Privatelist<string> list =NewArraylist<string>(); -      the @Override -     protected voidonCreate (Bundle savedinstancestate) { -         Super. OnCreate (savedinstancestate); - Setcontentview (r.layout.activity_main); + InitData (); -LV =(ListView) Findviewbyid (R.ID.ID_MAIN_LV); +myadapter<string> adapter =NewMyadapter<string> (list, This); A Lv.setadapter (adapter); at     } -  -     Private voidInitData () { -          for(inti=0;i<30;i++){ -List.add ("QQQQQ" +i); -         } in     } -  to      +}

  1  <relativelayout xmlns:android= "Http://schemas.android.com/apk/res /android " xmlns:tools=" Http://schemas.android.com/tools " 3  android:layout_width= "match_parent"  4  android:layout_height=" match _parent " 5  > 6   7  <listview   8  Android:id = "@+id/id_main_lv"  android:layout_width=" wrap_content "10  android:layout_height= "wrap_content" 12  

1  PackageCom.example.listviewdemo;2 3 Importjava.util.List;4 5 ImportAndroid.content.Context;6 ImportAndroid.view.View;7 ImportAndroid.view.ViewGroup;8 ImportAndroid.widget.BaseAdapter;9 ImportAndroid.widget.TextView;Ten  One  Public classMyadapter<t>extendsBaseadapter { A  -     PrivateList<t>list; -     PrivateContext Mcontext; the      PublicMyadapter (list<t>List,context Mcontext) { -         Super(); -          This. List =list; -          This. Mcontext =Mcontext; +     } -  +      A @Override at      Public intGetCount () { -         //TODO auto-generated Method Stub -         returnlist.size (); -     } -  - @Override in      PublicObject GetItem (intposition) { -         //TODO auto-generated Method Stub to         returnList.get (position); +     } -  the @Override *      Public LongGetitemid (intposition) { $         //TODO auto-generated Method StubPanax Notoginseng         returnposition; -     } the  + @Override A      PublicView GetView (intposition, View Convertview, ViewGroup parent) { the          +Viewholder holder =NULL; -         if(Convertview = =NULL){ $Holder =NewViewholder (); $Convertview = View.inflate (Mcontext, R.layout.item_listview,NULL); -Holder.tv =(TextView) Convertview.findviewbyid (R.ID.ITEM_TV); - Convertview.settag (holder); the}Else{ -Holder =(Viewholder) Convertview.gettag ();Wuyi         } the Holder.tv.setText (String) list.get (position)); - System.out.println (String) list.get (position)); Wu         returnConvertview; -     } About  $      classviewholder{ - TextView TV; -     } -}

1<?xml version= "1.0" encoding= "Utf-8"?>2<linearlayout xmlns:android= "Http://schemas.android.com/apk/res/android"3Android:layout_width= "Match_parent"4android:layout_height= "Match_parent"5android:layout_gravity= "Center"6android:orientation= "Vertical" >7 8<TextView9Android:id= "@+id/item_tv"TenAndroid:textsize= "15SP" OneAndroid:layout_width= "Wrap_content" Aandroid:layout_height= "Wrap_content"/> -  -</LinearLayout>

Make a ListView high efficiency universal Adapter