demo06

city_data.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>

    <string-array name="city_labels">
        <item>中国－北京</item>
        <item>中国－上海</item>
        <item>中国－长沙</item>
    </string-array>

</resources>

============
string.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>

    <string name="app_name" >demo06OnItemSelectedListener
    </string>
    <string name="action_settings" >Settings
    </string>
    <string name="hello_world" >Hello world!
    </string>
    <string name="city_list" >Hello world!
    </string>

</resources>
============================

main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:orientation="vertical"
    android:layout_height="match_parent"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/info"
        android:text="@string/city_list"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
    />

    <Spinner
        android:id="@+id/city"
        android:prompt="@string/city_list"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:entries="@array/city_labels"
    />

</LinearLayout>
==============================

package com.example.demo06onitemselectedlistener;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Spinner;
import android.widget.TextView;

public class MainActivity extends Activity {
    private Spinner city= null;
    private TextView info = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        this.city=(Spinner)super.findViewById(R.id.city);
        this.info=(TextView)super.findViewById(R.id.info);
        this.city.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> adapterView, View view, int idx, long id) {

               String value = adapterView.getItemAtPosition(idx).toString();
                MainActivity.this.info.setText("you best like city is:"+value);
            }

            @Override
            public void onNothingSelected(AdapterView<?> adapterView) {

            }
        });
    }

    @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;
    }

}