package android.basic.lesson13;
import android.app.Activity;
import android.content.Context;
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 MainHelloGallery extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
//定义UI组件
final ImageView iv= (ImageView)findViewById(R.id.ImageView01);
Gallery g = (Gallery) findViewById(R.id.Gallery01);
//设置图片匹配器
g.setAdapter(new ImageAdapter(this));
//设置AdapterView点击监听器，Gallery是AdapterView的子类
g.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
//显示点击的是第几张图片
Toast.makeText(MainHelloGallery.this, "" + position,
Toast.LENGTH_LONG).show();
//设置背景部分的ImageView显示当前Item的图片
iv.setImageResource(((ImageView)view).getId());
}
});
}
//定义继承BaseAdapter的匹配器
public class ImageAdapter extends BaseAdapter {
//Item的修饰背景
int mGalleryItemBackground;
//上下文对象
private Context mContext;
//图片数组
private Integer[] mImageIds = { R.drawable.wallpaper_0,
R.drawable.wallpaper_1, R.drawable.wallpaper_2,
R.drawable.wallpaper_3, R.drawable.wallpaper_4,
R.drawable.wallpaper_5, R.drawable.wallpaper_6,
R.drawable.wallpaper_7, R.drawable.wallpaper_8,
R.drawable.wallpaper_9 };
//构造方法
public ImageAdapter(Context c){
mContext = c;
//读取styleable资源
TypedArray a = obtainStyledAttributes(R.styleable.HelloGallery);
mGalleryItemBackground = a.getResourceId(
R.styleable.HelloGallery_android_galleryItemBackground, 0);
a.recycle();
}
//返回项目数量
@Override
public int getCount() {
return mImageIds.length;
}
//返回项目
@Override
public Object getItem(int position) {
return position;
}
//返回项目Id
@Override
public long getItemId(int position) {
return position;
}
//返回视图
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ImageView iv = new ImageView(mContext);
iv.setImageResource(mImageIds[position]);
//给生成的ImageView设置Id，不设置的话Id都是-1
iv.setId(mImageIds[position]);
iv.setLayoutParams(new Gallery.LayoutParams(120, 160));
iv.setScaleType(ImageView.ScaleType.FIT_XY);
iv.setBackgroundResource(mGalleryItemBackground);
return iv;
}
}
}
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