GridView的标准写法

MainActivity

public class MainActivity extends Activity {

    private GridView gd;
    private List<Picture> list;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        initView();
        initData();
        processData();

    }

    private void initView() {
        gd = (GridView) findViewById(R.id.gd);
    }

    private void initData() {
        list = new ArrayList<Picture>();
        // 只能有7张图片，再多就oom了，下次解决图片过多oom的问题
        list.add(new Picture(R.drawable.iv1));
        list.add(new Picture(R.drawable.iv2));
        list.add(new Picture(R.drawable.iv3));
        list.add(new Picture(R.drawable.iv4));
        list.add(new Picture(R.drawable.iv5));
        list.add(new Picture(R.drawable.iv6));
        list.add(new Picture(R.drawable.iv7));

    }

    private void processData() {
        MyAdapter myAdapter = new MyAdapter(getApplication(), list);
        gd.setAdapter(myAdapter);
    }

}

MyAdapter

public class MyAdapter extends BaseAdapter {
    private Context context;
    private List<Picture> list;

    public MyAdapter(Context context, List list) {
        this.context = context;
        this.list = list;
    }

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

    @Override
    public Object getItem(int position) {
        return null;
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder = new ViewHolder();
        if (convertView == null) {
            // 复用历史缓存对象
            convertView = View.inflate(context, R.layout.item_grid, null);
        }

        holder.iv_icon = (ImageView) convertView.findViewById(R.id.iv_icon);
        Picture picture = list.get(position);
        holder.iv_icon.setBackgroundResource(picture.getRes());

        return convertView;
    }

    /**
     * 减少findViewById次数
     */
    private class ViewHolder {
        ImageView iv_icon;
    }

}

JavaBean

public class Picture {
private int res;

public Picture(int res) {
    super();
    this.res = res;
}

public int getRes() {
    return res;
}

public void setRes(int res) {
    this.res = res;
}

}

布局文件

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.gridviewDemo.MainActivity" >

    <GridView
        android:id="@+id/gd"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:numColumns="3" >
    </GridView>

</RelativeLayout>

item

<?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:gravity="center_horizontal"
    android:orientation="vertical" >

    <ImageView
        android:id="@+id/iv_icon"
        android:layout_width="100dip"
        android:layout_height="70dip"
        android:layout_marginTop="5dip"
        android:background="@drawable/ic_launcher" />

</LinearLayout>

效果