Spinners--Android基本下拉框

Spinners–Android基本下拉框api文档：developer.android.com/reference/a…

在布局文件中添加spinners元素：

<Spinner
    android:id="@+id/planets_spinner"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content" />

最简单的例子：

Spinner spinner = (Spinner) findViewById(R.id.spinner);
// 创建一个ArrayAdapter，使用string array和 默认的spinner布局
String[] strings = getResources().getStringArray(R.array.planets_array);
ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(this,
                android.R.layout.simple_spinner_item, strings);
// 当列表被选择出现时指定展示的布局
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// 设置适配器
spinner.setAdapter(adapter);

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string-array name="planets_array">
        <item>1</item>
        <item>2</item>
        <item>3</item>
        <item>4</item>
        <item>5</item>
        <item>6</item>
        <item>7</item>
        <item>8</item>
    </string-array>
</resources>

监听事件：

spinner.setOnItemSelectedListener(new OnItemSelectedListener() {

    @Override
    public void onItemSelected(AdapterView<?> parent, View view,
            int position, long id) {
    //当item被选择时parent.getItemAtPosition(position)
    Toast.makeText(MainActivity.this,
    parent.getItemAtPosition(position).toString(),Toast.LENGTH_LONG).show();

    }

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

    }
});

自定义adapter

下拉框单个条目的布局item_spinner.xml：

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

    <TextView
        android:id="@+id/name"
        android:layout_width="100dp"
        android:layout_height="50dp"
        android:background="@null"
        android:padding="15dp"
        android:marqueeRepeatLimit="marquee_forever"
        android:ellipsize="marquee"
        android:singleLine="true" />

</LinearLayout>

MainActivity的布局包含下拉框，背景是自己的一张照片：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:background="#FFFFFF"
    android:layout_height="match_parent" 
    >

    <Spinner
        android:id="@+id/spinner"
        android:layout_width="100dp"
        android:layout_height="50dp"
        android:background="@drawable/btn_identyfy_code"
        android:popupBackground="@null"
        android:layout_alignParentTop="true"
        android:gravity="center"
      />

</RelativeLayout>

创建了一个ItemBean.java：

package com.yunmo.spinner;

public class ItemBean {

    private String ItemName;
    private int ItemId;


    public ItemBean(String itemName, int itemId) {
        super();
        ItemName = itemName;
        ItemId = itemId;
    }

    public String getItemName() {
        return ItemName;
    }

    public void setItemName(String itemName) {
        ItemName = itemName;
    }

    public int getItemId() {
        return ItemId;
    }

    public void setItemId(int itemId) {
        ItemId = itemId;
    }
}

适配器：

package com.yunmo.spinner;

import java.util.List;
import java.util.zip.Inflater;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;


public class mySpinnerAdapter extends BaseAdapter{

    private Context context;
    private List<ItemBean> list;

    public mySpinnerAdapter(Context context , List<ItemBean> list) {
        this.context = context;
        this.list = list;
    }

    @Override
    public int getCount() {
        return list.size();

    }

    @Override
    public ItemBean getItem(int position) {
        return list.get(position);

    }

    @Override
    public long getItemId(int position) {
        return position;

    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        if (convertView == null) {
            convertView =LayoutInflater.from(context).inflate(R.layout.item_spinner, null);
        }
        TextView name = (TextView) convertView.findViewById(R.id.name);
        name.setText(getItem(position).getItemName());

        return convertView;

    }


}

MainActivity里的代码：

package com.yunmo.spinner;

import java.util.ArrayList;
import java.util.List;

import android.app.Activity;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Toast;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.Spinner;

public class MainActivity extends Activity {

    private Spinner spinner;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        spinner = (Spinner) findViewById(R.id.spinner);

        List<ItemBean> list = new ArrayList<ItemBean>();
        list.add(new ItemBean("宝马aaaaaaaaaaa",10000));
        list.add(new ItemBean("a马bbbbbbbbb",10001));
        list.add(new ItemBean("b马ccccccccc",10002));
        list.add(new ItemBean("c马dddddddd",10003));

        mySpinnerAdapter adapter = new mySpinnerAdapter(this, list);
        spinner.setAdapter(adapter);
        spinner.setOnItemSelectedListener(new OnItemSelectedListener() {

            @Override
            public void onItemSelected(AdapterView<?> parent, View view,
                    int position, long id) {
                ItemBean itemBean = (ItemBean)parent.getItemAtPosition(position);
                Toast.makeText(MainActivity.this, itemBean.getItemId()+"", Toast.LENGTH_LONG).show();
            }

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

        });
    }
}