Android网格布局GridView学习使用

<?xml version="1.0" encoding="utf-8"?> 
<GridView xmlns:android="http://schemas.android.com/apk/res/android" 
 android:id="@+id/gridview" 
 android:layout_width="fill_parent" 
 android:layout_height="fill_parent" 
 android:numColumns="auto_fit" 
 android:verticalSpacing="10dp" 
 android:horizontalSpacing="10dp" 
 android:columnWidth="90dp" 
 android:stretchMode="columnWidth" 
 android:gravity="center" 
/> 

package com.yarin.android.Examples_04_19; 
 
import android.content.Context; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.BaseAdapter; 
import android.widget.GridView; 
import android.widget.ImageView; 
 
public class ImageAdapter extends BaseAdapter 
{ 
 // 定义Context 
 private Context  mContext; 
 // 定义整型数组 即图片源 
 private Integer[] mImageIds = 
 { 
   R.drawable.img_1, 
   R.drawable.img_2, 
   R.drawable.img_3, 
   R.drawable.img_4, 
   R.drawable.img_5, 
   R.drawable.img_6, 
   R.drawable.img_7, 
   R.drawable.img_8, 
   R.drawable.img_1, 
 }; 
 
 public ImageAdapter(Context c) 
 { 
  mContext = c; 
 } 
 
 // 获取图片的个数，从而知道需要加载的Item的数目与getView（）配合循环加载 
 public int getCount() 
 { 
  return mImageIds.length; 
 } 
 
 // 获取图片在库中的位置 
 public Object getItem(int position) 
 { 
  return position; 
 } 
 
 
 // 获取图片ID 
 public long getItemId(int position) 
 { 
  return position; 
 } 
 
 
 public View getView(int position, View convertView, ViewGroup parent) 
 { 
  ImageView imageView; 
  if (convertView == null) 
  { 
   // Item没有被加载过，给ImageView设置资源 
   imageView = new ImageView(mContext); 
   // 设置布局 图片60*60显示 
   imageView.setLayoutParams(new GridView.LayoutParams(65, 65)); 
   // 设置显示比例类型 
   imageView.setScaleType(ImageView.ScaleType.CENTER_INSIDE); 
  } 
  else 
  { 
   //Item已经被加载过，直接返回convertView 
   imageView = (ImageView) convertView; 
  } 
 
  imageView.setImageResource(mImageIds[position]); 
  return imageView; 
 } 
 
} 

package com.yarin.android.Examples_04_19; 
 
import android.app.Activity; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.AdapterView; 
import android.widget.GridView; 
import android.widget.Toast; 
import android.widget.AdapterView.OnItemClickListener; 
 
public class Activity01 extends Activity 
{ 
  
 @Override 
 public void onCreate(Bundle savedInstanceState) 
 { 
  super.onCreate(savedInstanceState); 
  setContentView(R.layout.main); 
 
  //取得GridView对象 
  GridView gridview = (GridView) findViewById(R.id.gridview); 
  //添加元素给gridview 
  gridview.setAdapter(new ImageAdapter(this)); 
 
  // 设置GridView的背景 
  gridview.setBackgroundResource(R.drawable.bg0); 
 
  //事件监听 
  gridview.setOnItemClickListener(new OnItemClickListener() { 
   public void onItemClick(AdapterView<?> parent, View v, int position, long id) 
   { 
    Toast.makeText(Activity01.this, "你选择了" + (position + 1) + " 号图片", Toast.LENGTH_SHORT).show(); 
   } 
  }); 
 } 
}