1.添加依赖

  implementation "androidx.viewpager2:viewpager2:1.0.0"

2.Activity代码

2.1 MainActivity.java

package com.example.demo_viewpager2;

import androidx.appcompat.app.AppCompatActivity;
import androidx.fragment.app.Fragment;
import androidx.viewpager2.adapter.FragmentStateAdapter;
import androidx.viewpager2.widget.ViewPager2;

import android.os.Bundle;

public class MainActivity extends AppCompatActivity {

    private static final int NUM_PAGES = 5;

    private ViewPager2 viewPager;

    private FragmentStateAdapter pagerAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        viewPager = findViewById(R.id.pager);
        pagerAdapter = new ScreenSlidePagerAdapter(this);
        //设置动画
        viewPager.setPageTransformer(new ZoomOutPageTransformer());
        viewPager.setAdapter(pagerAdapter);
    }

	//返回事件，当不是第一个的时候，返回上一个Fragment，是第一个就返回桌面
    @Override
    public void onBackPressed() {
        if (viewPager.getCurrentItem() == 0) {
            super.onBackPressed();
        } else {
            viewPager.setCurrentItem(viewPager.getCurrentItem() - 1);
        }
    }

	//页面滑动适配器
    private class ScreenSlidePagerAdapter extends FragmentStateAdapter {
        public ScreenSlidePagerAdapter(MainActivity fa) {
            super(fa);
        }

        @Override
        public Fragment createFragment(int position) {
            return new ScreenSlidePageFragment();
        }

        @Override
        public int getItemCount() {
            return NUM_PAGES;
        }
    }
}

2.2 activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <!-- activity_screen_slide.xml -->
    <androidx.viewpager2.widget.ViewPager2
        android:id="@+id/pager"
        android:layout_width="match_parent"
        android:layout_height="200dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />


</androidx.constraintlayout.widget.ConstraintLayout>

3.Fragment代码

3.1ScreenSlidePageFragment.java

package com.example.demo_viewpager2;

import android.os.Bundle;

import androidx.fragment.app.Fragment;

import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;


public class ScreenSlidePageFragment extends Fragment {


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_screen_slide_page, container, false);
    }
}

3.2 fragment_screen_slide_page.xml

<!-- fragment_screen_slide_page.xml -->
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/content"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <TextView style="?android:textAppearanceMedium"
        android:padding="16dp"
        android:lineSpacingMultiplier="1.2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/lorem_ipsum" />
</ScrollView>

4.过渡动画

4.1 ZoomOutPageTransformer.java

package com.example.demo_viewpager2;

import android.view.View;

import androidx.viewpager2.widget.ViewPager2;

public class ZoomOutPageTransformer implements ViewPager2.PageTransformer {
    private static final float MIN_SCALE = 0.85f;
    private static final float MIN_ALPHA = 0.5f;

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

        if (position < -1) { // [-Infinity,-1)
            // This page is way off-screen to the left.
            view.setAlpha(0f);

        } else if (position <= 1) { // [-1,1]
            // Modify the default slide transition to shrink the page as well
            float scaleFactor = Math.max(MIN_SCALE, 1 - Math.abs(position));
            float vertMargin = pageHeight * (1 - scaleFactor) / 2;
            float horzMargin = pageWidth * (1 - scaleFactor) / 2;
            if (position < 0) {
                view.setTranslationX(horzMargin - vertMargin / 2);
            } else {
                view.setTranslationX(-horzMargin + vertMargin / 2);
            }

            // Scale the page down (between MIN_SCALE and 1)
            view.setScaleX(scaleFactor);
            view.setScaleY(scaleFactor);

            // Fade the page relative to its size.
            view.setAlpha(MIN_ALPHA +
                    (scaleFactor - MIN_SCALE) /
                            (1 - MIN_SCALE) * (1 - MIN_ALPHA));

        } else { // (1,+Infinity]
            // This page is way off-screen to the right.
            view.setAlpha(0f);
        }
    }
}

5.最终效果