Android Programming Pull-down Menu Spinner Usage Summary (attached 2 example) _android

This paper gives a detailed summary and analysis of the Android programming pull-down menu spinner usage. Share to everyone for your reference, specific as follows:

The spinner control is also a list-type control, and its inheritance relationship is as follows:

Java.lang.Object
↳android.view.view
↳android.view.viewgroup
↳android.widget.adapterview<textends android.widget.adapter>
↳android.widget.absspinner
↳android.widget.spinner

Android.widget.Spinner inherits the Android.view.ViewGroup class .

In Android UI development, Spinner (Drop-down list) is always available, a simple custom Spinner production we just need to remember this important five steps, a Spinner can be applied and born.

(1) A new Android project, named Spinner. At the same time to build an activity, named Spinneractivity.

(2) Modify Res/layout/main.xml

<?xml version= "1.0" encoding= "Utf-8"?> <linearlayout xmlns:android= 
"http://schemas.android.com/apk/" Res/android " 
 android:orientation=" vertical " 
 android:layout_width=" fill_parent " 
 android:layout_" height= "Fill_parent" 
 > 
 <textview 
 android:id = "@+id/textview_city" 
 android:layout_width = " Wrap_content " 
 android:layout_height =" Wrap_content " 
 android:text =" City: " 
 /> 
 <!-- Define a city information drop-down menu--> 
 <spinner 
 android:id = "@+id/spinner_city" 
 android:layout_width = "Wrap_ Content " 
 android:layout_height =" Wrap_content "> 
 </spinner > 
</LinearLayout>

(3) Spinneractivity.java Code

Package cn.com; 
Import java.util.ArrayList; 
Import java.util.List; 
Import android.app.Activity; 
Import Android.os.Bundle; 
Import android.view.MotionEvent; 
Import Android.view.View; 
Import Android.widget.AdapterView; 
Import Android.widget.ArrayAdapter; 
Import Android.widget.Spinner; 
Import Android.widget.TextView; The public class Spinneractivity extends activity {/** called the ' when the ' is the ' is ' the ' activity ' is a-created private List<stri 
 ng> list = new arraylist<string> (); 
 Private TextView Mytextview; 
 Private Spinner Myspinner; 
 Private arrayadapter<string> adapter; 
 @Override public void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate); 
 Setcontentview (R.layout.main); 
 First step: Add a list of dropdown items, where the items added are Drop-down list menu items list.add ("Beijing"); 
 List.add ("Shanghai"); 
 List.add ("Shenzhen"); 
 List.add ("Fuzhou"); 
 List.add ("Xiamen"); 
 Mytextview = (TextView) Findviewbyid (r.id.textview_city); 
 Myspinner = (Spinner) Findviewbyid (r.id.spinner_city); Step two: Define an adapter for the Drop-down list,Here we use the list defined in the front. adapter = new Arrayadapter<string> (this,android.
 R.layout.simple_spinner_item, list); 
 Step Three: Set the menu style for the adapter when you drop down the Drop-down list. Adapter.setdropdownviewresource (Android. 
 R.layout.simple_spinner_dropdown_item); 
 Step Fourth: Add the adapter to the Drop-down list on Myspinner.setadapter (adapter); Step Fifth: Set up a response to a variety of events for the Drop-down list, the Response menu is selected Myspinner.setonitemselectedlistener (new Spinner.onitemselectedlistener () {public 
  void onitemselected (adapterview<?> arg0, View arg1, int arg2, long arg3) {//TODO auto-generated method stub 
  /* Bring the selected Myspinner value into the Mytextview/Mytextview.settext ("Your choice is:" + adapter.getitem (arg2)); 
  /* Will myspinner display * * arg0.setvisibility (view.visible); public void onnothingselected (adapterview<?> arg0) {//TODO auto-generated method stub Mytextview.settex 
  T ("NONE"); 
  Arg0.setvisibility (view.visible); 
 } 
 }); /* Drop-down Menu Popup Content Options Touch-screen event handling/Myspinner.setontouchlistener (new Spinner.ontouchlistener () {public boolean Ontouch (View V, Moti OnEvent event) {//TODO auto-generated Method Stub/** * */return false; 
 } 
 }); /* Drop-down Menu Popup Content option focus Change event handling/Myspinner.setonfocuschangelistener (new Spinner.onfocuschangelistener () {public void 
 Onfocuschange (View V, boolean hasfocus) {//TODO auto-generated Method stub}});

 } 
}

The results of the operation are shown in the following illustration:

Add: Spinner Control Usage Example 2

Usage 1:

<linearlayout xmlns:android= "http://schemas.android.com/apk/res/android"
 xmlns:tools= "http:// Schemas.android.com/tools "
 android:id=" @+id/container "
 android:orientation=" vertical "
 android: Layout_width= "Fill_parent"
 android:layout_height= "fill_parent"
 tools:context= "com.example.mars_2100_" Spinner. Mainactivity "
 tools:ignore=" Mergerootframe ">
<spinner android:layout_width=" Fill_parent
 " android:layout_height= "Wrap_content"
 android:id= "@+id/spinnerid"/>
</LinearLayout>

Package Com.example.mars_2100_spinner;
Import android.support.v7.app.ActionBarActivity;
Import Android.support.v7.app.ActionBar;
Import android.support.v4.app.Fragment;
Import Android.os.Bundle;
Import Android.view.LayoutInflater;
Import Android.view.Menu;
Import Android.view.MenuItem;
Import Android.view.View;
Import Android.view.ViewGroup;
Import Android.widget.AdapterView;
Import Android.widget.ArrayAdapter;
Import Android.widget.Spinner;
Import Android.widget.Toast;
Import Android.os.Build;
 public class Mainactivity extends Actionbaractivity {private static final string[] M_arr = {"First group", "second group", "third Group"};
 @Override protected void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate);
 Setcontentview (R.layout.activity_main);
 Spinner _spin = (Spinner) Findviewbyid (R.id.spinnerid); arrayadapter<string> ada = new Arrayadapter<string> (this, Android.
 R.layout.simple_spinner_item, M_arr); Ada.setdropdownviewresource (Android. R.layout.simple_spinner_dropdown_item);
 _spin.setadapter (ADA); _spin.setonitemselectedlistener (New Spinner.onitemselectedlistener () {public void onitemselected (ADAPTERVIEW&LT;?
  > arg0, View arg1, int arg2, long arg3) {disptoast ("select +m_arr[arg2]");
  Arg0.setvisibility (view.visible);
 public void onnothingselected (adapterview<?> arg0) {//}}); /*if (savedinstancestate = = null) {Getsupportfragmentmanager (). BeginTransaction (). Add (R.id.container, new
 Placeholderfragment ()). commit ();
 }*/} public void Disptoast (String str) {toast.maketext (this, str, toast.length_short). Show (); @Override public boolean Oncreateoptionsmenu (Menu menu) {//Inflate the menu; This adds the items to the action bar if I
 T is present.
 Getmenuinflater (). Inflate (R.menu.main, menu);
 return true; @Override public boolean onoptionsitemselected (MenuItem Item) {//Handle Action Bar item clicks here. The action bar would//automatically handle clicks on the Home/up button, so long//As you specify a parent aCtivity in Androidmanifest.xml.
 int id = item.getitemid ();
 if (id = = r.id.action_settings) {return true;
 return super.onoptionsitemselected (item);
 }/** * A placeholder fragment containing a simple view. */public static class Placeholderfragment extends Fragment {public placeholderfragment () {} @Override public View Oncreateview (Layoutinflater inflater, ViewGroup container, Bundle savedinstancestate) {View Rootview = inflater.inflate
  (R.layout.fragment_main, container, false);
 return rootview;

 }
 }
}

Usage 2:

<linearlayout xmlns:android= "http://schemas.android.com/apk/res/android"
 xmlns:tools= "http:// Schemas.android.com/tools "
 android:id=" @+id/container "
 android:orientation=" vertical "
 android: Layout_width= "Fill_parent"
 android:layout_height= "fill_parent"
 tools:context= "com.example.mars_2100_" Spinner. Mainactivity "
 tools:ignore=" Mergerootframe ">
<spinner android:layout_width=" Fill_parent
 " android:layout_height= "Wrap_content"
 android:id= "@+id/spinnerid2"/> <textview android:id=
"@+id/" TextView1 "
 android:layout_width=" fill_parent "
 android:layout_height=" wrap_content "/>
< Spinner android:layout_width= "fill_parent" android:layout_height= wrap_content "android:id=" @+id/
 SpinnerId3 "/>
<textview android:id=
 @+id/textview2" android:layout_width= "Fill_parent" android:layout_height= "Wrap_content"/>
</LinearLayout>

Package Com.example.mars_2100_spinner;
Import android.support.v7.app.ActionBarActivity;
Import Android.support.v7.app.ActionBar;
Import android.support.v4.app.Fragment;
Import android.app.Activity;
Import Android.os.Bundle;
Import Android.view.LayoutInflater;
Import Android.view.Menu;
Import Android.view.MenuItem;
Import Android.view.View;
Import Android.view.ViewGroup;
Import Android.widget.AdapterView;
Import Android.widget.AdapterView.OnItemSelectedListener;
Import Android.widget.ArrayAdapter;
Import Android.widget.Spinner;
Import Android.widget.TextView;
Import Android.os.Build;  public class Main02activity extends activity {Static final string[] constellations = new string[] {"Aries", "Taurus", "Gemini",
 "Cancer", "Leo", "Virgo", "Libra", "Scorpio", "Sagittarius", "Magic Scorpion", "Aquarius", "Pisces"};
 @Override protected void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate);
 Setcontentview (R.LAYOUT.ACTIVITY_MAIN02);
 Final TextView txt2 = (TextView) Findviewbyid (R.ID.TEXTVIEW1); Spinner S1= (Spinner) Findviewbyid (R.ID.SPINNERID2); Final arrayadapter<charsequence> adapter = Arrayadapter.createfromresource (this, R.array.planets_array, Android.
 R.layout.simple_spinner_item); Adapter.setdropdownviewresource (Android.
 R.layout.simple_spinner_dropdown_item);
 S1.setadapter (adapter);
 S1.setprompt ("test"); S1.setonitemselectedlistener (New Onitemselectedlistener () {@Override public void onitemselected (ADAPTERVIEW&LT;?
  > Parent, view view, int position, long id) {Txt2.settext (Adapter.getitem (position). ToString ());
  @Override public void onnothingselected (adapterview<?> parent) {Txt2.settext ("unchecked");
 }
 });
 Final TextView TXT4 = (TextView) Findviewbyid (R.ID.TEXTVIEW2);
 Spinner s2 = (Spinner) Findviewbyid (R.ID.SPINNERID3); arrayadapter<charsequence> Adapterc = new Arrayadapter<charsequence> (this, Android.
 R.layout.simple_spinner_item, constellations); Adapterc.setdropdownviewresource (Android.
 R.layout.simple_spinner_item); S2.setadaptER (ADAPTERC); S2.setonitemselectedlistener (New Onitemselectedlistener () {public void onitemselected (adapterview<?> parent,
  View view, int position, long id) {Txt4.settext (constellations[position]);
  public void onnothingselected (adapterview<?> parent) {Txt4.settext ("unchecked");
 }
 }); @Override public boolean Oncreateoptionsmenu (Menu menu) {//Inflate the menu; This adds the items to the action bar if I
 T is present.
 Getmenuinflater (). Inflate (r.menu.main02, menu);
 return true; @Override public boolean onoptionsitemselected (MenuItem Item) {//Handle Action Bar item clicks here.  The action bar would//automatically handle clicks on the Home/up button, so long//as your specify a parent activity in
 androidmanifest.xml. int id = item.getitemid ();
 if (id = = r.id.action_settings) {return true;
 return super.onoptionsitemselected (item);
 }/** * A placeholder fragment containing a simple view. */public static class Placeholderfragment extends Fragment {public placeholderfragment () {} @Override public View oncreateview (layoutinflater inflater, ViewGroup con
  Tainer, Bundle savedinstancestate) {View Rootview = inflater.inflate (R.layout.fragment_main02, container, false);
 return rootview;

 }
 }
}

<?xml version= "1.0" encoding= "Utf-8"?>
<resources>
 <string name= "App_name" >mars_2100_ spinner</string>
 <string name= "Hello_world" >hello world!</string>
 "<string name=" Action_settings ">Settings</string>
 <string-array name=" Planets_array ">
 <item> mercury</item>
 <item>Venus</item>
 <item>Earth</item>
 <item> mars</item>
 <item>Jupiter</item>
 <item>Saturn</item>
 <item> uranus</item>
 <item>Neptune</item>
 </string-array>
 <string name= " Title_activity_main02 ">Main02Activity</string>
</resources>

I hope this article will help you with the Android program.