轮播图ViewPager基本写法

public class MainActivity extends Activity {
private ViewPager viewpager;
private Context context = MainActivity.this;
// 准备要显示的图片资源
private int[] imageIdArray = { R.drawable.iv1, R.drawable.iv2,
R.drawable.iv3, R.drawable.iv4 };

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// 找到ViewPager控件
viewpager = (ViewPager) findViewById(R.id.viewpager);
// 给ViewPager设置适配器，要重写下面四个方法
viewpager.setAdapter(new PagerAdapter() {

@Override
public boolean isViewFromObject(View arg0, Object arg1) {
return arg0 == arg1;
}

@Override
public int getCount() {
return imageIdArray.length;
}

@Override
public Object instantiateItem(ViewGroup container, int position) {
View view = View
.inflate(context, R.layout.viewpager_item, null);
ImageView imageView = (ImageView) view.findViewById(R.id.image);
imageView.setImageResource(imageIdArray[position]);
// ★★★这句话很重要！！！别忘了写！！！
((ViewPager) container).addView(view);
return view;
}

@Override
public void destroyItem(ViewGroup container, int position,
Object object) {
// ★★★这句话很重要！！！别忘了写！！！
((ViewPager) container).removeView((View) object);
}
});
}
}

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="185dp" >

<android.support.v4.view.ViewPager
android:id="@+id/viewpager"
android:layout_width="wrap_content"
android:layout_height="wrap_content" >
</android.support.v4.view.ViewPager>

</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<ImageView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/image"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="fitXY" >

</ImageView>