Android开发中ViewPager实现多页面切换效果

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

public class MyPagerAdapter extends PagerAdapter {
private Context mContext;
private int[] mResId;
public MyPagerAdapter(Context context, int[] resId) {
this.mContext = context;
this.mResId = resId;
}
//设置内部pager页面的数量
@Override
public int getCount() {
return mResId.length;
}
@Override
public boolean isViewFromObject(View view, Object object) {
//判断页面与object是否是同一个对象
return view == object;
}
//必须重新覆写instaniateItem()和destroyItem()二个方法才能进行展示
@Override
public Object instantiateItem(ViewGroup container, int position) {
View view = View.inflate(mContext, R.layout.item, null);
View iv_item = view.findViewById(R.id.iv_item);
iv_item.setBackgroundResource(mResId[position]);
//必须将填充出来的view添加到ViewGroup中去,其container表示当前页面的容器
container.addView(view);
return view;
}
//不使用的时候,将其销毁
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
//父类实现的方法是抛异常(源码)
// super.destroyItem(container, position, object);
container.removeView((View) object);
}
}

public class MainActivity extends Activity {
private ViewPager mUp;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initeView();
initData();
}
private void initData() {
int[] resId = new int[]{R.drawable.shi, R.drawable.ni, R.drawable.haha};
//给ViewPager设置内容
MyPagerAdapter adapter = new MyPagerAdapter(getApplicationContext(), resId);
mUp.setAdapter(adapter);
}
private void initeView() {
mUp = (ViewPager) findViewById(R.id.up);
}
}