An example analysis of spinner control usage in the development of Android programming _android

This example describes the spinner control usage of Android programming. Share to everyone for your reference, specific as follows:

Drop-down list Spinner,spinner is a control that can only select one item at a time for all items. Its entry comes from the adapter associated with it.

The use of spinner can greatly improve the experience of users. When you need a user selection, you can provide a drop-down list of all the optional items listed. For the user to choose.

One, using arrays as data sources

Layout file:

<relativelayout xmlns:android= "http://schemas.android.com/apk/res/android" 
 xmlns:tools= "http:// Schemas.android.com/tools " 
 android:layout_width=" match_parent " 
 android:layout_height=" Match_parent " 
 android:paddingbottom= "@dimen/activity_vertical_margin" 
 android:paddingleft= "@dimen/activity_ Horizontal_margin " 
 android:paddingright=" @dimen/activity_horizontal_margin " 
 android:paddingtop=" @dimen /activity_vertical_margin " 
 tools:context=". Mainactivity "> 
 <spinner 
  android:id=" @+id/spinner1 "android:layout_width=" Match_parent " 
  android:layout_height= "wrap_content" 
  android:layout_alignparentleft= "true" 
  android:layout_ Alignparenttop= "true"/> 
</RelativeLayout>

Mainactivity.java

Package Com.example.lesson16_spinner; 
Import java.util.ArrayList; 
Import Java.util.HashMap; 
Import java.util.List; 
Import Java.util.Map; 
Import android.app.Activity; 
Import Android.os.Bundle; 
Import Android.view.Menu; 
Import Android.view.View; 
Import Android.widget.AdapterView; 
Import Android.widget.ArrayAdapter; 
Import Android.widget.SimpleAdapter; 
Import Android.widget.Spinner; 
Import Android.widget.Toast; 
 public class Mainactivity extends activity {//Declare Spinner object private Spinner Spinner; 
  @Override protected void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate); 
  Setcontentview (R.layout.activity_main); 
  Spinner = (spinner) Findviewbyid (R.id.spinner1); 
  Use an array as the data source final String arr[] = new string[] {"Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Week Seven"}; Adpater object Arrayadapter<string> arrayadapter = new Arrayadapter<string> (this, Android. 
  R.layout.simple_spinner_item, arr); List<map<string, Object>> daTa = new arraylist<map<string, object>> (); 
  map<string, object> map = new hashmap<string, object> (); 
  Map.put ("logo", r.drawable.ic_launcher); 
  Map.put ("text", "xxxx description operation"); 
  map<string, object> map2 = new hashmap<string, object> (); 
  Map2.put ("logo", r.drawable.ic_launcher); 
  Map2.put ("text", "xxx description xxx"); 
  Data.add (map); 
  Data.add (MAP2); Simpleadapter simpleadapter = new Simpleadapter (this, data, R.layout.activity_item, new string[] {"logo", "Text"}, new I 
  Nt[] {r.id.imageview1, r.id.textview1}); 
  Sets the displayed data Spinner.setadapter (arrayadapter); 
  Spinner.setadapter (Simpleadapter); Toast.maketext (Getapplicationcontext (), "main Thread" + spinner.getitematposition (spinner.getselecteditemposition ( 
  ), Toast.length_long). Show (); Register Event Spinner.setonitemselectedlistener (new Adapterview.onitemselectedlistener () {@Override public void Onit 
  Emselected (adapterview<?> Parent, view view, int position, long ID) {  String content = Arr[position]; 
    Spinner Spinner = (Spinner) parent; 
   Toast.maketext (Getapplicationcontext (), "xxxx" + spinner.getitematposition (position), Toast.length_long). Show (); @Override public void onnothingselected (adapterview<?> parent) {Toast.maketext (getapplicationcontext 
   (), "No change of Processing", Toast.length_long). Show (); 
 } 
  }); @Override public boolean Oncreateoptionsmenu (Menu menu) {//Inflate the menu; This adds items to the action Bar 
  If it is present. 
  Getmenuinflater (). Inflate (R.menu.main, menu); 
 return true;

 } 
}

The effect is as follows:

Ii. using XML as a data source (not my Code)

Layout file:

<?xml version= "1.0" encoding= "Utf-8"?> 
<resources> 
 <string-array name= "Plantes" > 
  <item>NOKIA</item> 
  <item>MOTO</item> 
  <item>HTC</item> 
  <item >LG</item> 
  <item> Other </item> 
 </string-array> 
</resources>

Java code:

Import android.app.Activity; 
Import Android.os.Bundle; 
Import Android.view.View; 
Import Android.widget.AdapterView; 
Import Android.widget.AdapterView.OnItemSelectedListener; 
Import Android.widget.ArrayAdapter; 
Import Android.widget.Spinner; 
Import Android.widget.TextView; 
 public class Spinneractivity extends activity {private TextView view2; 
 Private Spinner Spinner2; 
 Private Arrayadapter Adapter2; @Override protected void OnCreate (Bundle savedinstancestate) {//TODO auto-generated method stub super.oncreate (s 
  Avedinstancestate); 
  Setcontentview (R.layout.spinner); 
  Spinner2 = (Spinner) Findviewbyid (R.ID.SPINNER02); 
  View2 = (TextView) Findviewbyid (r.id.spinnertext02); Connect the optional content to the Arrayadapter Adapter2 = Arrayadapter.createfromresource (this, R.array.plantes, Android. 
  R.layout.simple_spinner_item); Set the style of the Drop-down list Adapter2.setdropdownviewresource (Android. 
  R.layout.simple_spinner_dropdown_item); Add Adapter2 to spinner Spinner2.setadapter (adapter2);
  Add Event Spinner Event Listener Spinner2.setonitemselectedlistener (New Spinnerxmlselectedlistener ()); 
 Set default value spinner2.setvisibility (view.visible); Use XML to manipulate class Spinnerxmlselectedlistener implements onitemselectedlistener{public void onitemselected (adapte 
  Rview<?> arg0, View arg1, int arg2, long arg3) {View2.settext ("What kind of cell phone do you use:" +adapter2.getitem (arg2));

 public void onnothingselected (Adapterview<?> arg0) {}}}

I hope this article will help you with your Android programming.