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介绍

屏幕滑动是两个完整屏幕之间的切换，在设置向导或幻灯片等界面中很常见

实现图(图片来源于网络):

例子

1、创建视图
我这里只创建了3个XML

fragment0.xml

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="https://schemas.android.com/apk/res/android"         android:id="@+id/content"         android:layout_width="match_parent"         android:layout_height="match_parent" > <ImageView         android:layout_width="match_parent"         android:layout_height="match_parent"         android:adjustViewBounds="true"         android:scaleType="fitXY"         android:src="@drawable/p0" /> </LinearLayout> 

fragment1.xml

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="https://schemas.android.com/apk/res/android"         android:id="@+id/content"         android:layout_width="match_parent"         android:layout_height="match_parent" > <ImageView         android:layout_width="match_parent"         android:layout_height="match_parent"         android:adjustViewBounds="true"         android:scaleType="fitXY"         android:src="@drawable/p1" /> </LinearLayout> 

fragment2.xml

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="https://schemas.android.com/apk/res/android"         android:id="@+id/content"         android:layout_width="match_parent"         android:layout_height="match_parent" > <ImageView         android:layout_width="match_parent"         android:layout_height="match_parent"         android:adjustViewBounds="true"         android:scaleType="fitXY"         android:src="@drawable/p2" /> </LinearLayout> 

2、创建 Fragment
根据构造方法传进来的 int i；返回不同的视图(i是等下用到的FragmentStateAdapter适配器中传进去的)

package com.example.xianyu; import android.os.Bundle; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import androidx.annotation.NonNull; import androidx.annotation.Nullable; import androidx.fragment.app.Fragment; public class mFragment extends Fragment { int i = 0; mFragment(int i){ this.i = i; } @Nullable @Override public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {         View view = null; switch (i){ case 0: {             view = inflater.inflate(R.layout.fragment0, container, false); break; } case 1: {             view =  inflater.inflate(R.layout.frament1, container, false); break; } case 2: {                 view = inflater.inflate(R.layout.fragment2, container, false); break; } } return view; } } 

3、主Activity，并创建自定义适配器继承自FragmentStateAdapter

activity_screen_slide.xml

<?xml version="1.0" encoding="utf-8"?> <!-- activity_screen_slide.xml --> <androidx.viewpager2.widget.ViewPager2     xmlns:android="https://schemas.android.com/apk/res/android"     android:id="@+id/pager"     android:layout_width="match_parent"     android:layout_height="match_parent" /> 

homeActivity

package com.example.xianyu; import android.os.Bundle; import androidx.fragment.app.Fragment; import androidx.fragment.app.FragmentActivity; import androidx.viewpager2.adapter.FragmentStateAdapter; import androidx.viewpager2.widget.ViewPager2; public class homeActivity extends FragmentActivity { //要显示的页数 private static final int NUM_PAGES = 3; private ViewPager2 viewPager2; // 适配器，为ViewPager2提供页面  private FragmentStateAdapter pagerAdapter; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_screen_slide);         viewPager2 = findViewById(R.id.pager);         pagerAdapter = new ScreenSlidePagerAdapter(this);         viewPager2.setAdapter(pagerAdapter); } @Override public void onBackPressed() { if (viewPager2.getCurrentItem() == 0) { super.onBackPressed(); } else {                        viewPager2.setCurrentItem(viewPager2.getCurrentItem() - 1); } } //自定义的类，继承自FragmentStateAdapter适配器 private class ScreenSlidePagerAdapter extends FragmentStateAdapter { public ScreenSlidePagerAdapter(FragmentActivity fa) { super(fa); } //主要是createFragment这个方法 @Override public Fragment createFragment(int position) { return new mFragment(position); } @Override public int getItemCount() { return NUM_PAGES; } } } 

总结

非常实用，快快叭！