ViewPager(4)用viewpager实现splash view

1，示例

2，代码

SplashMain.java

 import android.os.Bundle;
 import android.support.v4.app.Fragment;
 import android.support.v4.view.ViewPager;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.LinearLayout;

 import com.txw.e.viewpager.R;
 import com.txw.e.viewpager.main.MainActivity;

 /**
  * A simple {@link Fragment} subclass.
  */
 public class SplashMain extends Fragment {

     //1，在layout.xml中添加 ViewPagerFragment,它可以是顶级布局，如下：
     /*
     <?xml version="1.0" encoding="utf-8"?>
     <android.support.v4.view.ViewPager
         android:id="@+id/splash_pager"
         xmlns:android="http://schemas.android.com/apk/res/android"
         android:layout_width="match_parent"
         android:layout_height="match_parent"/>
     */

     //2，准备变量,ViewPager和 PagerAdapter ,OnPageChangeListener
     ViewPager pager;
     SplashViewPagerAdapter pagerAdapter;

     //3，初始化pager
     void initPager(View v){
         //从layout.xml中初始化pager
         pager = (ViewPager) v.findViewById(R.id.splash_pager);

         //初始化page adapter
         pagerAdapter = new SplashViewPagerAdapter(getFragmentManager());

         //设置adapter
         pager.setAdapter(pagerAdapter);

         //设置page切换监听者
         pager.addOnPageChangeListener(onPageChangeListener);

         //设置pager切换动画
 //        pager.setPageTransformer(true, new DepthPageTransformer());

     }

     //4，处理 pager 切换事件
     //这里用的ViewPager.SimpleOnPageChangeListener,它什么也不做。
     ViewPager.OnPageChangeListener onPageChangeListener = new ViewPager.OnPageChangeListener() {
         @Override
         public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
             if (positionOffset == ){
                 for (int i = ; i < indexer.getChildCount(); ++i){
                     View v = indexer.getChildAt(i);
                     if (i == position){
                         v.setBackgroundResource(R.drawable.splash_indexer_focused);
                     }else{
                         v.setBackgroundResource(R.drawable.splash_indexer);
                     }
                 }
             }
         }

         @Override
         public void onPageSelected(int position) {

         }

         @Override
         public void onPageScrollStateChanged(int state) {

         }
     };

     //5，重写切换动画类，可以把这个类放到外面去。
     public class DepthPageTransformer implements ViewPager.PageTransformer {
         private static final float MIN_SCALE = 0.75f;

         public void transformPage(View view, float position) {
             int pageWidth = view.getWidth();

             if (position < -) { // [-Infinity,-1)
                 // This page is way off-screen to the left.
                 view.setAlpha();

             } else if (position <= ) { // [-1,0]
                 // Use the default slide transition when moving to the left page
                 view.setAlpha();
                 view.setTranslationX();
                 view.setScaleX();
                 view.setScaleY();

             } else if (position <= ) { // (0,1]
                 // Fade the page out.
                 view.setAlpha( - position);

                 // Counteract the default slide transition
                 view.setTranslationX(pageWidth * -position);

                 // Scale the page down (between MIN_SCALE and 1)
                 float scaleFactor = MIN_SCALE
                         + ( - MIN_SCALE) * ( - Math.abs(position));
                 view.setScaleX(scaleFactor);
                 view.setScaleY(scaleFactor);

             } else { // (1,+Infinity]
                 // This page is way off-screen to the right.
                 view.setAlpha();
             }
         }
     }

     LinearLayout    indexer;

     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
         // Inflate the layout for this fragment
         View v = inflater.inflate(R.layout.fragment_splash_main, container, false);

         initPager(v);

         indexer = (LinearLayout) v.findViewById(R.id.splash_indexer);

         return v;
     }

     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         MainActivity aty = (MainActivity) getActivity();
         aty.getSupportActionBar().hide();
     }

     @Override
     public void onDestroy() {
         super.onDestroy();
         MainActivity aty = (MainActivity) getActivity();
         aty.getSupportActionBar().show();
     }
 }

SplashViewPagerAdapter.java

 import android.support.v4.app.Fragment;
 import android.support.v4.app.FragmentManager;
 import android.support.v4.app.FragmentStatePagerAdapter;

 public class SplashViewPagerAdapter extends FragmentStatePagerAdapter {

     public SplashViewPagerAdapter(FragmentManager fm) {
         super(fm);

     }

     @Override
     public Fragment getItem(int position) {
         SplashFragment fragment = new SplashFragment();
         fragment.colorId = position;
         return fragment;
     }

     @Override
     public int getCount() {
         return ;
     }
 }

SplashFragment.java

 public class SplashFragment extends Fragment {

     public int colors[] = {Color.BLUE,Color.CYAN,Color.GREEN,Color.MAGENTA};

     public View    rootView;
     public int     colorId;

     View.OnClickListener clickListener = new View.OnClickListener(){

         @Override
         public void onClick(View v) {
             if (colorId == ){
                 getFragmentManager().popBackStack();
             }
         }
     };

     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
                              Bundle savedInstanceState) {
         // Inflate the layout for this fragment
         rootView = inflater.inflate(R.layout.fragment_splash, container, false);

         rootView.setBackgroundColor(colors[colorId]);

         rootView.setOnClickListener(clickListener);

         return rootView;
     }

 }

3，xml

fragment_splash_main.xml

 <?xml version="1.0" encoding="utf-8"?>

 <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
     android:background="#FFFFFF">

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

     <LinearLayout
         android:id="@+id/splash_indexer"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_gravity="bottom|center_horizontal"
         android:layout_marginBottom="30dp"
         android:orientation="horizontal">

         <TextView
             android:layout_width="wrap_content"
             android:layout_height="match_parent"
             android:layout_gravity="center_horizontal"
             android:background="@drawable/splash_indexer"/>

         <TextView
             android:layout_width="wrap_content"
             android:layout_height="match_parent"
             android:layout_gravity="center_horizontal"
             android:background="@drawable/splash_indexer"/>

         <TextView
             android:layout_width="wrap_content"
             android:layout_height="match_parent"
             android:layout_gravity="center_horizontal"
             android:background="@drawable/splash_indexer"/>

         <TextView
             android:layout_width="wrap_content"
             android:layout_height="match_parent"
             android:layout_gravity="center_horizontal"
             android:background="@drawable/splash_indexer"/>
     </LinearLayout>

 </FrameLayout>

fragment_splash.xml

 <FrameLayout 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:background="#FFFFFF"
              tools:context="com.txw.e.viewpager.splash.SplashFragment">
 </FrameLayout>

drawable/splash_indexer_focused.xml

 <?xml version="1.0" encoding="utf-8"?>
 <shape xmlns:android="http://schemas.android.com/apk/res/android"
        android:shape="oval">
     <!--<gradient-->
         <!--android:endColor="#f793ac"-->
         <!--android:gradientRadius="50"-->
         <!--android:startColor="#fa1621"-->
         <!--android:type="radial"/>-->

     <solid android:color="#FFFFFF" />
     <size android:width="20dp" android:height="20dp"/>

 </shape>

drawable/splash_indexer.xml

 <?xml version="1.0" encoding="utf-8"?>
 <shape xmlns:android="http://schemas.android.com/apk/res/android"
        android:shape="oval">
     <gradient
         android:endColor="#fa1621"
         android:gradientRadius="50"
         android:startColor="#f793ac"
         android:type="radial"/>
     <size
         android:width="20dp"
         android:height="20dp"/>

 </shape>