GridView组件的应用

GridView组件，可以应用到照片显示，浏览图片等功能。

下面就就是一个小例子：

一 布局：

1) 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="fill_parent"
    android:layout_height="fill_parent" 
    android:background="@drawable/bg">

    <GridView
        android:id="@+id/imagelist"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:horizontalSpacing="20dp"
        android:numColumns="2"
        android:verticalSpacing="10dp" >
    </GridView>

    <ImageView
        android:id="@+id/imageshow"
        android:layout_marginTop="20dp"
        android:scaleType="centerInside"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"/>

</LinearLayout>

2)grid.xml:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    
    <ImageView
        android:id="@+id/smallImage"
        android:layout_width="80dp"
        android:layout_height="50dp"/>

</LinearLayout>

二 中心文件

MainActivity.java:

public class MainActivity extends Activity {
	private GridView imageList;
	private ImageView imageShow;
	private int[] pics;

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		// 查找组件
		imageList = (GridView) findViewById(R.id.imagelist);
		imageShow = (ImageView) findViewById(R.id.imageshow);
		pics = new int[] { R.drawable.image1, R.drawable.image2,
				R.drawable.image3, R.drawable.image4, R.drawable.image5,
				R.drawable.image6 };
		// 准备要添加的数据条目
		List<Map<String, Object>> pic_items = new ArrayList<Map<String, Object>>();
		for (int pic_id : pics) {
			Map<String, Object> item = new HashMap<String, Object>();
			item.put("pic", pic_id);
			item.put("text", "第" + (pic_id + 1) + "幅图片");
			pic_items.add(item);
		}
		// 实例化适配器
		SimpleAdapter adapter = new SimpleAdapter(this, pic_items,
				R.layout.grid, new String[] { "pic", "text" },
				new int[] { R.id.smallImage });
		imageList.setAdapter(adapter);
		imageShow.setImageResource(pics[0]);
		imageList.setOnItemClickListener(new OnItemClickListener() {

			@Override
			public void onItemClick(AdapterView<?> adapter, View view,
					int position, long id) {
				imageShow.setImageResource(pics[position]);

			}
		});
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}

}

结果如图显示：