Android进阶之欢迎滑动页面(最简洁方法)

一、效果图

二、源码

1.activity_welcome_guide.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

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

    <Button
        android:id="@+id/welcome_guide_btn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:layout_marginBottom="80dp"
        android:background="@mipmap/guide_button"
        android:paddingLeft="30dp"
        android:paddingRight="30dp"
        android:visibility="gone" />

RelativeLayout>

2.WelcomeGuideActivity.java

/**
 * 滑动页面
 *
 * @author Guan
 * @file com.guan.dianping.activity
 * @date 2015/11/3
 * @Version 1.0
 */
public class WelcomeGuideActivity extends FrameActivity {

    @ViewInject(R.id.welcome_guide_btn)
    private Button btn;
    @ViewInject(R.id.welcome_pager)
    private ViewPager pager;
    private List list;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_welcome_guide);
        ViewUtils.inject(this);
        init();
        initViewPager();
    }

    @OnClick(R.id.welcome_guide_btn)
    public void click(View view) {
        //页面的跳转
        startActivity(new Intent(getBaseContext(), MainActivity.class));
        finish();
    }

    //初始化
    public void init() {
        list = new ArrayList();
    }

    //初始化ViewPager的方法
    public void initViewPager() {
        ImageView iv1 = new ImageView(this);
        iv1.setImageResource(R.mipmap.guide_01);
        ImageView iv2 = new ImageView(this);
        iv2.setImageResource(R.mipmap.guide_02);
        ImageView iv3 = new ImageView(this);
        iv3.setImageResource(R.mipmap.guide_03);
        list.add(iv1);
        list.add(iv2);
        list.add(iv3);

        pager.setAdapter(new MyPagerAdapter());
        //监听ViewPager滑动效果
        pager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            //页卡被选中的方法
            @Override
            public void onPageSelected(int arg0) {
                //如果是第三个页面
                if (arg0 == 2) {
                    btn.setVisibility(View.VISIBLE);
                } else {
                    btn.setVisibility(View.GONE);
                }
            }

            @Override
            public void onPageScrolled(int arg0, float arg1, int arg2) {
            }

            @Override
            public void onPageScrollStateChanged(int arg0) {
            }
        });
    }

    //定义ViewPager的适配器
    class MyPagerAdapter extends PagerAdapter {
        //计算需要多少item显示
        @Override
        public int getCount() {
            return list.size();
        }

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

        //初始化item实例方法
        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            container.addView(list.get(position));
            return list.get(position);
        }

        //item销毁的方法
        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            // 注销父类销毁item的方法，因为此方法并不是使用此方法
//          super.destroyItem(container, position, object);
            container.removeView(list.get(position));
        }
    }
}