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本文以一个简单的小例子,简述Android开发中GridView的常见应用,仅供学习分享使用。

概述

GiridView是一个表格显示资源的控件,可以在两个可滚动的方向上显示。列表项的资源会通过ListAdapter自动添加到布局控件中GirdView上。

如下图所示:

 

数据绑定步骤

如下图所示:

 涉及知识点

  • android:numColumns="auto_fit"  设置GridView中的列数,可以是数字,auto_fit表示系统自动根据屏幕的大小进行适应性显示。
  • android:verticalSpacing="10dp” 用于设置行与行之间的垂直间隔
  • android:horizontalSpacing="10dp" 用于设置列与列之间的水平间隔
  • android:stretchMode="columnWidth" 设置列中元素的拉伸模式
  • setOnItemClickListener 设置列元素的监听事件

示例效果图

如下图所示:

核心代码

GridView如下:

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <RelativeLayout
 3     xmlns:android="http://schemas.android.com/apk/res/android"
 4     xmlns:tools="http://schemas.android.com/tools"
 5     android:layout_width="match_parent"
 6     android:layout_height="match_parent"
 7     tools:context="com.hex.demogridview.MainActivity">
 8     <GridView
 9         android:id="@+id/gv_info"
10         android:columnWidth="90dp"
11         android:verticalSpacing="10dp"
12         android:horizontalSpacing="10dp"
13         android:numColumns="auto_fit"
14         android:stretchMode="columnWidth"
15         android:layout_width="match_parent"
16         android:layout_height="match_parent"></GridView>
17 </RelativeLayout>

列表项代码(图片和文本)

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3               android:layout_width="match_parent"
 4               android:layout_height="match_parent"
 5               android:orientation="vertical">
 6     <ImageView
 7         android:id="@+id/img_info"
 8         android:src="@drawable/a011"
 9         android:layout_width="match_parent"
10         android:layout_height="wrap_content"/>
11     <TextView
12         android:id="@+id/tv_info"
13         android:text="abc"
14         android:textSize="20sp"
15         android:textAlignment="center"
16         android:textColor="@color/colorAccent"
17         android:layout_width="match_parent"
18         android:layout_height="wrap_content"/>
19 </LinearLayout>

后台代码(Adapter类)

 1 class  MyAdapter extends BaseAdapter {
 2         private Context mContext;
 3 
 4         public MyAdapter(Context context) {
 5             this.mContext = context;
 6         }
 7 
 8         @Override
 9         public int getCount() {
10             return mList != null ? mList.size() : 0;
11         }
12 
13         @Override
14         public Object getItem(int position) {
15             return mList.get(position);
16         }
17 
18         @Override
19         public long getItemId(int position) {
20             return position;
21         }
22 
23         @Override
24         public View getView(int position, View convertView, ViewGroup parent) {
25             ViewHolder viewHolder;
26             if (convertView == null) {
27                 // if it's not recycled, initialize some attributes
28                 LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE); //getLayoutInflater();
29                 convertView = inflater.inflate(R.layout.grid_item,null);
30                 viewHolder=new ViewHolder();
31                 viewHolder.img = (ImageView) convertView.findViewById(R.id.img_info);
32                 viewHolder.tv = (TextView) convertView.findViewById(R.id.tv_info);
33 
34                 convertView.setTag(viewHolder);
35             } else {
36                 viewHolder = (ViewHolder) convertView.getTag();
37             }
38             viewHolder.img.setImageResource((int)mList.get(position).get("img"));
39             viewHolder.tv.setText((String) mList.get(position).get("txt"));
40             return convertView;
41         }
42     }

后台代码(Activity)

 1 public class MainActivity extends AppCompatActivity {
 2     private  int[] imgs;
 3     private List<Map<String,Object>> mList;
 4    private  GridView gvInfo;
 5     @Override
 6     protected void onCreate(Bundle savedInstanceState) {
 7         super.onCreate(savedInstanceState);
 8         setContentView(R.layout.activity_main);
 9         gvInfo= (GridView) this.findViewById(R.id.gv_info);
10 
11         imgs=new int[]{R.drawable.a011,R.drawable.a012,R.drawable.a013,R.drawable.a014,R.drawable.a015,R.drawable.a016,
R.drawable.a017,R.drawable.a018,R.drawable.a019,R.drawable.a0110,R.drawable.a0111};
12 mList=new ArrayList<Map<String, Object>>(); 13 for(int i=0;i<11;i++) { 14 Map<String, Object> map = new HashMap<String, Object>(); 15 map.put("img", imgs[i]); 16 map.put("txt", "第" + i + "个"); 17 mList.add(map); 18 } 19 MyAdapter adapter =new MyAdapter(this); 20 gvInfo.setAdapter(adapter); 21 gvInfo.setOnItemClickListener(new AdapterView.OnItemClickListener() { 22 @Override 23 public void onItemClick(AdapterView<?> parent, View view, int position, long id) { 24 TextView textView= (TextView) view.findViewById(R.id.tv_info); 25 String msg = textView.getText().toString(); 26 Toast.makeText(MainActivity.this,msg,Toast.LENGTH_SHORT).show(); 27 } 28 }); 29 30 }

备注

学习一门新的语言,坚持的源头是兴趣,坚持的前方是希望。

posted on 2019-02-01 23:22 Alan.hsiang 阅读(...) 评论(...) 编辑 收藏