Android Learning-----Spinner

Android gives us a spinner control, which is basically a list, so let's say this control, this control has been seen in the past, but this is still a new introduction again. Spinner is located under the Android.widget package, displaying only the user-selected element at a time, and when the user taps again, a selection list pops up for the user to select, and the elements from the selection list are also from the adapter. Spinner is a subclass of the view class. Here is a concrete look at what's going on:

1.:

2.XML Code

1 <?XML version= "1.0" encoding= "Utf-8"?>2 <LinearLayoutxmlns:android= "Http://schemas.android.com/apk/res/android"3 Android:id= "@+id/widget28"4 Android:layout_width= "Fill_parent"5 Android:layout_height= "Fill_parent"6 android:orientation= "vertical" >7 8     <TextView9         Android:id= "@+id/textview_show"Ten Android:layout_width= "Fill_parent" One Android:layout_height= "Wrap_content" A Android:text= "You chose to be" - android:textsize= "25SP" > -     </TextView> the  -     <Spinner -         Android:id= "@+id/spinner_city" - Android:layout_width= "Fill_parent" + Android:layout_height= "Wrap_content" > -     </Spinner> +  A </LinearLayout>

3.java Code

1  PackageCom.example.spinner;2 3 Importjava.util.ArrayList;4 Importjava.util.List;5 Importandroid.app.Activity;6 ImportAndroid.os.Bundle;7 ImportAndroid.view.View;8 ImportAndroid.widget.AdapterView;9 ImportAndroid.widget.ArrayAdapter;Ten ImportAndroid.widget.Spinner; One ImportAndroid.widget.TextView; A  -  Public classMainactivityextendsActivity { -  the     Privatelist<string> list =NewArraylist<string>(); -     PrivateTextView Mytextview; -     PrivateSpinner Myspinner; -     PrivateArrayadapter<string>adapter; +  - @Override +      Public voidonCreate (Bundle savedinstancestate) { A         Super. OnCreate (savedinstancestate); at Setcontentview (r.layout.activity_main); - Initspinner (); -     } -  -     Private voidInitspinner () { -         //First step: Add a list of drop-down list items, and the items you add here are the menu items for the drop-down list inList.add ("Beijing")); -List.add ("Shanghai"); toList.add ("Shenzhen"); +List.add ("Nanjing"); -List.add ("Chongqing"); theMytextview =(TextView) Findviewbyid (r.id.textview_show); *Myspinner =(Spinner) Findviewbyid (r.id.spinner_city); $         //Step Two: Define an adapter for the drop-down list, which is used in the list defined in the previous section. Panax Notoginsengadapter =NewArrayadapter<string> ( This, - Android. R.layout.simple_spinner_item, list); the         //Step Three: Set the menu style for the adapter drop-down list.  + Adapter.setdropdownviewresource (Android. R.layout.simple_spinner_dropdown_item); A         //Fourth Step: Add the adapter to the drop-down list the Myspinner.setadapter (adapter); +         //Fifth Step: Set the response of various events for the drop-down list, the Response menu is selected - Myspinner $. Setonitemselectedlistener (NewSpinner.onitemselectedlistener () { $                      Public voidOnitemselected (adapterview<?>arg0, View arg1, -                             intArg2,LongArg3) { -                         //TODO auto-generated Method Stub the                         /*bring the value of the selected Myspinner into the Mytextview*/ -Mytextview.settext ("You have selected:" +Adapter.getitem (arg2));Wuyi                         /*Display the Myspinner*/ the arg0.setvisibility (view.visible); -                     } Wu  -                      Public voidOnnothingselected (adapterview<?>arg0) { About                         //TODO auto-generated Method Stub $                         //mytextview.settext ("NONE"); -                         //arg0.setvisibility (view.visible); -                     } -                 }); A     } +}

Android Learning-----Spinner