Android——利用BaseAdapter实现GridView

Android学习一点一点进步！

• 设置布局
• 设置子项布局
• 定义BaseAdapter
• 设置MainActivity

先写个主框架

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="horizontal">

    <GridView
        android:id="@+id/lv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">

    </GridView>
</LinearLayout>

再来个模板

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center_vertical">
<ImageView
    android:id="@+id/item_image"
    android:layout_width="48dp"
    android:layout_height="48dp"
    android:layout_margin="8dp"
    android:background="@drawable/jd"/>
    <TextView
        android:id="@+id/item_tv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="京东商城"
        android:textSize="20sp" />
</LinearLayout>

设置Mainactivity

public class MainActivity extends Activity {
    private GridView mGridView;
    private String[] names={"京东商城","QQ","QQ斗地主","新浪微博","天猫","UC浏览器","微信"};
    private int[] icons={R.drawable.jd,R.drawable.qq,R.drawable.dz,R.drawable.xl,R.drawable.tm,R.drawable.uc,R.drawable.wx};
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.listview);
        mGridView=(GridView)findViewById(R.id.lv);
        MyBaseAdapter mAdapter=new MyBaseAdapter();
        mGridView.setAdapter(mAdapter);
        mGridView.setNumColumns(3);
    }

    class MyBaseAdapter extends BaseAdapter{

        @Override
        public int getCount() {
            return names.length;
        }

        @Override
        public Object getItem(int position) {
            return names[position];
        }

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

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ViewHolder holder;
            if (convertView == null) {
                convertView = LayoutInflater.from(
                        getApplicationContext()).inflate(R.layout.activity_main,null);
                holder=new ViewHolder();
                holder.mTexTView=convertView.findViewById(R.id.item_tv);
                holder.imageView=convertView.findViewById(R.id.item_image);
                convertView.setTag(holder);
            }else {
             holder=(ViewHolder) convertView.getTag();
            }
            holder.mTexTView.setText(names[position]);
            holder.imageView.setBackgroundResource(icons[position]);
            return convertView;
        }
        class ViewHolder{
            TextView mTexTView;
            ImageView imageView;
        }
    }
}

 

就是这样，虽然很丑