首先在app-src-main-res-layout下建立3個Layout Resource File檔案

第一個介面程式碼

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

    <TextView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="layout1"
        android:textSize="30sp"
        android:background="#ff00ff"/>
</androidx.constraintlayout.widget.ConstraintLayout>

第二個介面程式碼

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

    <TextView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="layout2"
        android:textSize="30sp"
        android:background="#ff99ff"/>
</androidx.constraintlayout.widget.ConstraintLayout>

第三個介面程式碼

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

    <TextView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="layout3"
        android:textSize="30sp"
        android:background="#ff7"/>
</androidx.constraintlayout.widget.ConstraintLayout>

activity_main.xml程式碼如下

<?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">

<androidx.viewpager.widget.ViewPager

//建立ViewPaper

    android:layout_width="match_parent"

    android:layout_height="match_parent"
    android:id="@+id/vp"/>
</androidx.constraintlayout.widget.ConstraintLayout>

MainActivity.java程式碼如下

package com.example.viewpager;

import androidx.appcompat.app.AppCompatActivity;
import androidx.viewpager.widget.ViewPager;

import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

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

        LayoutInflater from = getLayoutInflater().from(this);
        View v1 = from.inflate(R.layout.layout1, null);
        View v2 = from.inflate(R.layout.layout2, null);
        View v3 = from.inflate(R.layout.layout3, null);

        List<View> viewList = new ArrayList<>();
        viewList.add(v1);
        viewList.add(v2);
        viewList.add(v3);

        ViewPager viewPager = findViewById(R.id.vp);

//獲取ViewPaper
//建立一個MyAdapter.java填充ViewPaper的佈局

　　
        MyAdapter myAdapter = new MyAdapter(viewList);
        viewPager.setAdapter(myAdapter);


    }
}

MyAdapter.java程式碼如下

package com.example.viewpager;

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

import androidx.annotation.NonNull;
import androidx.viewpager.widget.PagerAdapter;

import java.util.List;

public class MyAdapter extends PagerAdapter {//這裡繼承PagerAdapter並實現裡面的方法，如果繼承後報錯可以按ALT+ENTER然後回車

    private List<View> viewList;

    public MyAdapter(List<View> viewList) {
        this.viewList = viewList;
    }

    @Override
    public int getCount() {//獲得ViewPaper中有多少個view
        return viewList.size();
    }

    @Override
    public boolean isViewFromObject(@NonNull View view, @NonNull Object object) {//判斷當前的物件和page是否對應

        return view==object;
    }

    @NonNull
    @Override
    public Object instantiateItem(@NonNull ViewGroup container, int position) {//一個Page在切換完成後會呼叫該方法去載入下一個即將展示的Page
        container.addView(viewList.get(position),0);
        return viewList.get(position);
    }

    @Override
    public void destroyItem(@NonNull ViewGroup container, int position, @NonNull Object object) {//移除一個給定位置的頁面
        container.removeView(viewList.get(position));
    }
}

最後附上專案結構圖，僅供參考。