View（视图）——ListView之BaseAdapter和SimpleCursorAdapter以及网格视图代码视图

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     xmlns:tools="http://schemas.android.com/tools"
 4     android:layout_width="match_parent"
 5     android:layout_height="match_parent"
 6     android:paddingBottom="@dimen/activity_vertical_margin"
 7     android:paddingLeft="@dimen/activity_horizontal_margin"
 8     android:paddingRight="@dimen/activity_horizontal_margin"
 9     android:paddingTop="@dimen/activity_vertical_margin"
10     tools:context="com.example.wang.testapp2.TestActivity10">
11 
12     <GridView
13         android:layout_width="match_parent"
14         android:layout_height="match_parent"
15         android:id="@+id/gv_1"
16         android:numColumns="4"
17         android:stretchMode="columnWidth"
18         android:gravity="center"
19         android:horizontalSpacing="30dp"
20         ></GridView>
21 
22 </LinearLayout>

 1 package com.example.wang.testapp2;
 2 
 3 import android.app.ActionBar;
 4 import android.support.v7.app.AppCompatActivity;
 5 import android.os.Bundle;
 6 import android.view.View;
 7 import android.view.ViewGroup;
 8 import android.widget.AbsListView;
 9 import android.widget.BaseAdapter;
10 import android.widget.GridView;
11 import android.widget.ImageView;
12 
13 import java.util.ArrayList;
14 import java.util.List;
15 
16 public class TestActivity10 extends AppCompatActivity {
17 
18     GridView gv_1;
19 
20     List<Integer> liv;
21 
22     @Override
23     protected void onCreate(Bundle savedInstanceState) {
24         super.onCreate(savedInstanceState);
25         setContentView(R.layout.activity_test10);
26 
27         GridView gv_1=(GridView)findViewById(R.id.gv_1);
28 
29         //1 数据 图片的id
30         liv =new ArrayList<>();
31         liv.add(R.drawable.f1);
32         liv.add(R.drawable.f2);
33         liv.add(R.drawable.f3);
34         liv.add(R.drawable.f4);
35         liv.add(R.drawable.f5);
36         liv.add(R.drawable.f6);
37         liv.add(R.drawable.f7);
38         liv.add(R.drawable.f8);
39         liv.add(R.drawable.f9);
40         liv.add(R.drawable.f10);
41 
42         gv_1.setAdapter(new ImageAdapter());
43 
44     }
45 
46     // 适配器
47 
48     class  ImageAdapter extends BaseAdapter
49     {
50         @Override
51         public int getCount() {
52             return liv.size();
53         }
54 
55         @Override
56         public Object getItem(int position) {
57             return liv.get(position);
58         }
59 
60         @Override
61         public long getItemId(int position) {
62             return 0;
63         }
64 
65         @Override
66         public View getView(int position, View convertView, ViewGroup parent) {
67 
68             //1. 得到数据 图片的id
69             Integer ivid=liv.get(position);
70 
71             //2.准备View
72             if (convertView==null)
73             {
74                 convertView = new ImageView(TestActivity10.this);
75             }
76 
77             //3.适配
78             // 转换
79             ImageView imageView=(ImageView)convertView;
80 
81             imageView.setImageResource(ivid);
82 
83 //            imageView.setMaxWidth(70);
84 //            imageView.setMaxHeight(70);
85 
86             imageView.setLayoutParams(new GridView.LayoutParams(110,110));
87 
88 
89             return imageView;
90         }
91     }
92 }