Android入门之GridView（纯Java）

Android入门之GridView（纯Java）

Android入门之GridView（纯Java）

1. import android.app.Activity;  
2. import android.content.Context;  
3. import android.graphics.Bitmap;  
4. import android.graphics.BitmapFactory;  
5. import android.graphics.Matrix;  
6. import android.os.Bundle;  
7. import android.view.View;  
8. import android.view.ViewGroup;  
9. import android.widget.BaseAdapter;  
10. import android.widget.GridView;  
11. import android.widget.ImageView;  
12.   
13. public class GridViewTest extends Activity {  
14.   
15.     private GridView gv=null;  
16.       
17.     public void onCreate(Bundle savedInstanceState) {  
18.         super.onCreate(savedInstanceState);  
19.         gv_init();  
20.         setContentView(gv);  
21.     }  
22.       
23.     /*gv初始化*/  
24.     void gv_init(){  
25.         gv=new GridView(this);  
26.         GridView.LayoutParams lp=new GridView.LayoutParams(-1,-1);  
27.         gv.setLayoutParams(lp);  
28.         gv.setColumnWidth(90);  
29.         gv.setNumColumns(GridView.AUTO_FIT);  
30.         gv.setVerticalSpacing(10);  
31.         gv.setHorizontalSpacing(10);  
32.         gv.setAdapter(new ImageAdapter(this));  
33.     }  
34.       
35.     /*ImageAdapter*/  
36.     public class ImageAdapter extends BaseAdapter {  
37.   
38.         private Context context;  
39.         //图片源数组   
40.         private Integer[] imageInteger = {R.drawable.p00,R.drawable.p01,  
41.                 R.drawable.p02,R.drawable.p03,  
42.                 R.drawable.p04,R.drawable.p05,  
43.                 R.drawable.p06,R.drawable.p07,  
44.                 R.drawable.p08,R.drawable.p09,  
45.                 R.drawable.p10,R.drawable.p11,  
46.                 R.drawable.p12,R.drawable.p13,  
47.                 R.drawable.p14,R.drawable.p15,  
48.                 R.drawable.p16,R.drawable.p17,  
49.                 R.drawable.p18,R.drawable.p19  
50.         };  
51.           
52.         public ImageAdapter(Context c) {  
53.             context = c;  
54.         }  
55.   
56.         public int getCount() {  
57.             return imageInteger.length;  
58.         }  
59.   
60.         public Object getItem(int position) {  
61.             return position;  
62.         }  
63.   
64.         public long getItemId(int position) {  
65.             return position;  
66.         }  
67.   
68.         public View getView(int position, View convertView, ViewGroup parent) {  
69.             ImageView imageView = new ImageView(context);  
70.             imageView.setLayoutParams(new GridView.LayoutParams(90,-2));  
71.             /*图片缩放处理，如果先设置了iamgeView的大小，则必须注意加载的图片大小不能超出，否则无法显示*/  
72.             Bitmap bm = BitmapFactory.decodeResource(context.getResources(),imageInteger[position]);  
73.             //原始尺寸   
74.             int width=bm.getWidth();  
75.             int height=bm.getHeight();  
76.             //缩放比例   
77.             if(width>90){  
78.                 float scaleWidth=((float)90)/width;  
79.                 float scaleHeight=scaleWidth;  
80.                 // 创建操作图片用的matrix对象       
81.                 Matrix matrix = new Matrix();     
82.                 // 缩放图片动作       
83.                 matrix.postScale(scaleWidth, scaleHeight);     
84.                 //旋转图片 动作       
85.                 //matrix.postRotate(45);      
86.                 // 创建新的图片       
87.                 Bitmap resizedBitmap = Bitmap.createBitmap(bm,0,0,width, height,matrix,true);     
88.                 imageView.setImageBitmap(resizedBitmap);  
89.             }else{  
90.                 imageView.setImageBitmap(bm);  
91.             }  
92.             imageView.setScaleType(ImageView.ScaleType.CENTER_INSIDE);  
93.             return imageView;  
94.         }  
95.     }  
96. }