Android高级组件Gallery画廊视图使用方法详解

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
 android:layout_width="fill_parent" 
 android:layout_height="fill_parent" 
 android:orientation="horizontal" 
 android:id="@+id/layout" 
 android:gravity="center"> 
 <Gallery 
 android:id="@+id/gallery1" 
 android:spacing="5px" 
 android:unselectedAlpha="0.6" 
 android:layout_width="match_parent" 
 android:layout_height="wrap_content"/> 
</LinearLayout> 

<?xml version="1.0" encoding="utf-8"?> 
<resources> 
 <declare-styleable name="Gallery"> 
 <attr name="android:galleryItemBackground"/> 
 </declare-styleable> 
</resources> 

package com.example.test; 
 
 
import android.app.Activity; 
import android.content.res.TypedArray; 
import android.os.Bundle; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.AdapterView; 
import android.widget.AdapterView.OnItemClickListener; 
import android.widget.BaseAdapter; 
import android.widget.Gallery; 
import android.widget.ImageView; 
import android.widget.Toast; 
 
 
public class MainActivity extends Activity{ 
 
 
 @Override 
 protected void onCreate(Bundle savedInstanceState) { 
 super.onCreate(savedInstanceState); 
 setContentView(R.layout.main); 
  
 Gallery gallery=(Gallery)findViewById(R.id.gallery1); 
 final int [] imageId=new int[]{R.drawable.img01,R.drawable.img02,R.drawable.img03,R.drawable.img04, 
  R.drawable.img05,R.drawable.img06,R.drawable.img07,R.drawable.img08, 
  R.drawable.img_top,R.drawable.ic_launcher,R.drawable.in,R.drawable.stop,};//定义并初始化保存图片id的数组 
 //创建并改写BaseAdapter适配器 
 BaseAdapter adapter=new BaseAdapter(){ 
 
 
  @Override 
  public View getView(int position, View convertView, ViewGroup parent) { 
  ImageView imageView;//声明一个ImageView的对象 
  if(convertView==null){ 
   imageView=new ImageView(MainActivity.this);//实例化ImageView对象 
   imageView.setScaleType(ImageView.ScaleType.FIT_XY);//设置缩放方式 
   imageView. setLayoutParams(new Gallery.LayoutParams(180, 135));//设置ImageView宽高 
   TypedArray typedArray=obtainStyledAttributes(R.styleable.Gallery);//获取自定义属性对象 
   //为imageView设置背景图片的资源，使用了自定义属性对象typedArray获取自定义背景资源值 
   imageView.setBackgroundResource( 
    typedArray.getResourceId(R.styleable.Gallery_android_galleryItemBackground, 0)); 
   imageView.setPadding(5, 0, 5, 0);//设置内边距 
  }else{ 
   //如果以前new过View就使用convertView的缓存 
   imageView=(ImageView)convertView; 
  } 
  imageView.setImageResource(imageId[position]); 
  return imageView; 
  } 
  
  //功能:获得当前选项的id 
  @Override 
  public long getItemId(int position) { 
  return position; 
  } 
  
  //功能：获得当前选项 
  @Override 
  public Object getItem(int position) { 
  return position; 
  } 
  
  //获得数量 
  @Override 
  public int getCount() { 
  return imageId.length; 
  } 
 
 
 }; 
  
 gallery.setAdapter(adapter); 
 gallery.setSelection(imageId.length/2); 
 gallery.setOnItemClickListener(new OnItemClickListener() { 
 
 
  @Override 
  public void onItemClick(AdapterView<?> parent, View v, int position, 
   long id) { 
  Toast.makeText(MainActivity.this, "您选择了第"+String.valueOf(position)+"张图片", 
    Toast.LENGTH_SHORT).show(); 
  } 
 }); 
 } 
}