Android UI之Gallery和ImageSwitcher

Gallery能显示多张图片，画廊效果。
ImageSwitch是图片切换器。

1、配置布局文件 main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" >
  <ImageSwitcher  android:id="@+id/imageSwitcher" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_centerInParent="true"/>
  <Gallery  android:id="@+id/gallery" android:layout_width="fill_parent" android:layout_height="wrap_content" android:spacing="8dp" android:layout_alignParentBottom="true"/>
</RelativeLayout>

2、程序主要代码 MainActivity.java

package com.yin.picture_view;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.BaseAdapter;
import android.widget.Gallery;
import android.widget.ImageSwitcher;
import android.widget.ImageView;
import android.widget.ViewSwitcher.ViewFactory;
public class MainActivity extends Activity {

    //显示图片的资源
    private  static int[] images = {
            R.drawable.s0 , R.drawable.s1,
            R.drawable.s2 , R.drawable.s3,
            R.drawable.s4 , R.drawable.s5,
            R.drawable.s6 , R.drawable.s7,
            R.drawable.s8 , R.drawable.s9   
        };
     Gallery gallery;
     ImageSwitcher is;
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        gallery = (Gallery) findViewById(R.id.gallery);
        is = (ImageSwitcher) findViewById(R.id.imageSwitcher);

        gallery.setAdapter(new ImageAdapter(this));
       //让选定的图片在中心显示
        gallery.setSelection(images.length/2);

        //为Gallery绑定监听器；
        gallery.setOnItemSelectedListener(new OnItemSelectedListener() {
            public void onItemSelected(AdapterView<?> parent, View view,
                    int position, long id) {
                //当在Gallery中选定一张图片是 ImageSwitcher同步显示同一张
                //position%images.length 为了让图片循环显示
                is.setImageResource(images[position%images.length]);

            }
            public void onNothingSelected(AdapterView<?> parent) {

            }
        });


        is.setFactory(new ImageFactory(this));

    }

    private class ImageAdapter extends BaseAdapter{
        private Context context;
        public ImageAdapter(Context context) {
            this.context = context;
        }
        //可以return images.lenght(),在这里返回Integer.MAX_VALUE
        //是为了使图片循环显示
        public int getCount() {
            return Integer.MAX_VALUE;
        }
        public Object getItem(int position) {
            return null;
        }
        public long getItemId(int position) {
            return 0;
        }
        public View getView(int position, View convertView, ViewGroup parent) {
            ImageView iv = new ImageView(context);
            iv.setImageResource(images[position%images.length]);
            iv.setLayoutParams(new Gallery.LayoutParams(90,90));
            iv.setAdjustViewBounds(true);
            return iv;
        }
    }

    private class ImageFactory implements ViewFactory{
        private Context context;
        public ImageFactory(Context context){
            this.context = context;
        }
        public View makeView() {
            ImageView iv = new ImageView(context);
            iv.setLayoutParams(new ImageSwitcher.LayoutParams(200,200));
            return iv;
        }
    }
}

3、效果图