下拉列表 spinner(android)

下拉列表 spinner，这个使用很简单，在 xml 中定义一个标签，然后指定 ArrayAdapter<String> 就可以了，

Adapter 需要指定下拉的布局。关于下拉的数据，书中是写用静态数组，我这里改成了从资源文件中读取

java 代码

package zziss.android.spinnerTest;

import java.util.Map;

import android.app.Activity;
import android.content.res.Resources;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.TextView;

public class SpinnerTestActivity extends Activity {
    /** Called when the activity is first created. */
    
    private TextView iTv;
    private Spinner  iSpinner;
    private String[] items;
    private ArrayAdapter<Map<String,Integer>> iAda;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        iTv = (TextView)this.findViewById(R.id.tv);
        iSpinner = (Spinner)this.findViewById(R.id.spinner);
        Resources res = getResources();
        items = res.getStringArray(R.array.listItems);
        ArrayAdapter<String> ada = new ArrayAdapter<String>(this,
                android.R.layout.simple_spinner_item,items);
        ada.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        
        iSpinner.setAdapter(ada);
        iSpinner.setOnItemSelectedListener(new Spinner.OnItemSelectedListener()
        {

            @Override
            public void onItemSelected(AdapterView<?> arg0, View arg1,
                    int arg2, long arg3) {
                // TODO Auto-generated method stub
                iTv.setText(items[arg2]);
            }

            

            @Override
            public void onNothingSelected(AdapterView<?> arg0) {
                // TODO Auto-generated method stub
                
            }
            
        });
    }
}

main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/tv"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="" />
    <Spinner 
        android:id="@+id/spinner"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        />
</LinearLayout>

string.xml

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

    <string name="hello">Hello World, SpinnerTestActivity!</string>
    <string name="app_name">SpinnerTest</string>
    <string-array name="listItems" >
        <item >A型</item>
        <item >B型</item>
        <item >AB型</item>
        <item >O型</item>
    </string-array>

</resources>