Spinner的功能和用法

Gallery和Spinner的共同父类是： AbsSpinner。他们都是列表框，区别有二：

1、Spinner显示的是垂直的列表框，而Gallery显示的是水平的列表框；

2、Spinner的作用是供用户选择，Gallery是用户拖动来查看上一个下一个列表项；

举个例子来分别说明Spinner的用法；Galler是不推荐的控件！

sample1(Spinner):

activity_main.xml：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.hct.spinner.MainActivity" >

    <Spinner
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:entries="@array/books" />

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

</LinearLayout>

MainActivity.java：

public class MainActivity extends Activity {

    private Spinner m_spinner;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        m_spinner = (Spinner) findViewById(R.id.spinner);
        String[] arr = new String[] { "孙悟空", "猪八戒", "唐僧" };

        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
                android.R.layout.simple_list_item_multiple_choice, arr);
        m_spinner.setAdapter(adapter);
    }

    @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;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
}