【Android开发】经典范例1-实现仿Windows7图片预览窗格效果

  
    android:orientation="horizontal"  
    android:layout_width="fill_parent"  
    android:layout_height="fill_parent"  
    android:id="@+id/layout1"
    >  
            android:layout_height="match_parent"
        android:layout_width="440px"
        android:layout_marginTop="10px"
        android:horizontalSpacing="3px"
        android:verticalSpacing="3px"
        android:numColumns="3"/>
    
            android:id="@+id/imageSwitcher1"
        android:padding="10px"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

package com.example.test;  
  
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewGroup.LayoutParams;
import android.view.animation.AnimationUtils;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageSwitcher;
import android.widget.ImageView;
import android.widget.ViewSwitcher.ViewFactory;
  
public class MainActivity extends Activity {  
    private int[] imageId=new int []{R.drawable.img1,R.drawable.img2,R.drawable.img3,R.drawable.img4,
            R.drawable.img5,R.drawable.img6,R.drawable.img7,R.drawable.img8,R.drawable.img9};
    private ImageSwitcher imageSwitcher;
    @Override  
    public void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.main);  
       
        imageSwitcher=(ImageSwitcher)findViewById(R.id.imageSwitcher1);//获取图像切换器
        //设置动画效果
        imageSwitcher.setInAnimation(AnimationUtils.loadAnimation(this, android.R.anim.fade_in));//设置淡入动画
        imageSwitcher.setOutAnimation(AnimationUtils.loadAnimation(this, android.R.anim.fade_out));//设置淡出动画
        imageSwitcher.setFactory(new ViewFactory() {
            
            @Override
            public View makeView() {
                //实例化一个ImageView对象
                ImageView imageView=new ImageView(MainActivity.this);
                //设置保持纵横比居中缩放图像
                imageView.setScaleType(ImageView.ScaleType.FIT_CENTER);
                imageView.setLayoutParams(new ImageSwitcher.LayoutParams(
                        LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT));
                return imageView;//返回imageView对象
            }
        });
        imageSwitcher.setImageResource(R.drawable.img3);//设置默认显示的图像
        
        
        GridView gridview=(GridView)findViewById(R.id.gridView1);
        BaseAdapter adapter=new BaseAdapter(){


            @Override
            public View getView(int position, View convertView, ViewGroup parent) {
                ImageView imageView = null;//声明一个ImageView对象
                if(convertView==null){
                    imageView=new ImageView(MainActivity.this);//实例化ImageView对象
                    /****************设置图像的宽度和高度*******************/
                    imageView.setAdjustViewBounds(true);
                    imageView.setMaxWidth(150);
                    imageView.setMaxHeight(113);
                    /*********************************************************/
                    imageView.setPadding(5, 5, 5, 5);
                }else{
                    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;
            }
        };
        gridview.setAdapter(adapter);
        gridview.setOnItemClickListener(new OnItemClickListener() {


            @Override
            public void onItemClick(AdapterView> parent, View view, int position,
                    long id) {
                    //显示选中的照片
                   imageSwitcher.setImageResource(imageId[position]);
            }
        });
    }  
}