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;

    }

}