导航页面轮播图viewpager,滑到最后一页显示按钮

activity_second.xml布局里

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    >    <android.support.v4.view.ViewPager        android:id="@+id/daohangview_pager"        android:layout_width="match_parent"        android:layout_height="match_parent">  </android.support.v4.view.ViewPager>    <Button        android:visibility="gone"        android:layout_centerHorizontal="true"        android:layout_alignParentBottom="true"        android:layout_marginBottom="10dp"        android:text="进入系统"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:id="@+id/button"        /></RelativeLayout>

SecondActivity里面的代码

public class SecondActivity extends AppCompatActivity {    private ViewPager viewPager;    private Button button;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);        setContentView(R.layout.activity_second);        button = (Button) findViewById(R.id.button);        viewPager = (ViewPager) findViewById(R.id.daohangview_pager);        //访问网络图片        final List<String> list = new ArrayList<>();        list.add("https://b-ssl.duitang.com/uploads/item/201502/07/20150207203154_yAhxW.thumb.700_0.jpeg");        list.add("https://b-ssl.duitang.com/uploads/item/201502/07/20150207204451_vUxdK.thumb.700_0.jpeg");        list.add("https://b-ssl.duitang.com/uploads/item/201502/07/20150207204612_khkBv.thumb.700_0.jpeg");        list.add("https://b-ssl.duitang.com/uploads/item/201502/07/20150207205514_uMz5u.thumb.700_0.jpeg");        list.add("https://b-ssl.duitang.com/uploads/item/201502/10/20150210133942_AaJ8R.thumb.700_0.jpeg");        DaohangAdapter daohangAdapter = new DaohangAdapter(list, SecondActivity.this);        viewPager.setAdapter(daohangAdapter);        //viewpager设置页面改变的监听        viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {            @Override            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {            }            @Override            public void onPageSelected(int position) {                if (list.size()-1 == position){                    //如果到了最后一页,就显示按钮                    button.setVisibility(View.VISIBLE);                }else{                    button.setVisibility(View.GONE);                }            }            @Override            public void onPageScrollStateChanged(int state) {            }        });        //按钮的点击事件        button.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View view) {                Intent intent = new Intent(SecondActivity.this, ThirdActivity.class);                startActivity(intent);                finish();            }        });    }}

适配器

public class DaohangAdapter extends PagerAdapter{    List<String> list;    Context context;    public DaohangAdapter(List<String> list, Context context) {        this.list = list;        this.context = context;    }    @Override    public int getCount() {        return list.size();    }    @Override    public boolean isViewFromObject(View view, Object object) {        return view==object;    }    @Override    public Object instantiateItem(ViewGroup container, int position) {        ImageView imageView = new ImageView(context);        imageView.setScaleType(ImageView.ScaleType.FIT_XY);        ImageLoader.getInstance().displayImage(list.get(position),imageView,ImageLoaderUtil.getDefautOption());        container.addView(imageView);        return imageView;    }    @Override    public void destroyItem(ViewGroup container, int position, Object object) {        container.removeView((View) object);    }}