Android Spinner（下拉菜单）的应用举例

AppMain.java

package lxy.litsoft;
import Android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.Toast;
public class AppMain extends Activity {
Spinner s;
ArrayAdapter<CharSequence> adapter;
public void onCreate（Bundle savedInstanceState） {
super.onCreate（savedInstanceState）;
setContentView（R.layout.main）;
adapter = ArrayAdapter.createFromResource（this, R.array.place, android.R.layout.simple_spinner_item）;
adapter.setDropDownViewResource（android.R.layout.simple_spinner_dropdown_item）;
s = （Spinner）findViewById（R.id.spinner）;
s.setAdapter（adapter）;
s.setOnItemSelectedListener（new SpinnerListener（））;
s.setPrompt（"地点"）;
}
class SpinnerListener implements OnItemSelectedListener{
public void onItemSelected（AdapterView<？> arg0, View arg1, int arg2,
long arg3） {
String selected = arg0.getItemAtPosition（arg2）.toString（）;
Toast.makeText（AppMain.this, "what you selected is :"+selected, Toast.LENGTH_LONG）.show（）;
Log.d（"test", "what you selected is :"+selected）;
}
public void onNothingSelected（AdapterView<？> arg0） {
Toast.makeText（AppMain.this, "you have selected nothing", Toast.LENGTH_LONG）.show（）;
Log.d（"test", "you have selected nothing"）;
}
}
}

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:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello"
/>
<Spinner
android:id="@+id/spinner"
android:layout_width="fill_parent"
android:layout_height="wrap_content"></Spinner>
</LinearLayout>

strings.xml

<？xml version="1.0" encoding="utf-8"？>
<resources>
<string name="hello">Hello World, AppMain！</string>
<string name="app_name">Spinner</string>
<string-array name="place">
<item>北京</item>
<item>河北</item>
<item>石家庄</item>
<item>邢台</item>
<item>广宗</item>
<item>小庄</item>
</string-array>
</resources>