ViewPager2总结

概述

ViewPager2是一个增强版的ViewPager，ViewPager2是基于RecyclerView+PagerSnapHelper实现的，解决了ViewPager的一些弊端，同时加入一些新特性。

常用API

//设置分页方向
setOrientation(@Orientation int orientation)//定位指定页面
setCurrentItem(int item)
setCurrentItem(int item, boolean smoothScroll)//设置预加载页数
setOffscreenPageLimit(@OffscreenPageLimit int limit)//禁止滑动
setUserInputEnabled(boolean enabled) //模拟滑动
beginFakeDrag()
fakeDragBy(float offsetPxFloat)
//停止模拟
endFakeDrag()//全部刷新
notifyDataSetChanged();
//局部刷新
notifyItemChanged(int position)//监听页面变化
registerOnPageChangeCallback(@NonNull OnPageChangeCallback callback)
//删除监听
unregisterOnPageChangeCallback(@NonNull OnPageChangeCallback callback)

ViewPager2基本使用

class ViewPager2SimpleActivity : BaseActivity() {private lateinit var viewPager2: ViewPager2private lateinit var indicator: LinearLayout//图片资源private val mImgIds =intArrayOf(R.drawable.a, R.drawable.b, R.drawable.c, R.drawable.d, R.drawable.e)companion object {fun start(context: Context) {val intent = Intent(context, ViewPager2SimpleActivity::class.java).apply {putExtra(KEY_TITLE, "ViewPager2基本使用")}context.startActivity(intent)}}override fun onCreate(savedInstanceState: Bundle?) {super.onCreate(savedInstanceState)setContentView(R.layout.activity_view_pager2_simple)initView()initViewPager2()}private fun initView() {viewPager2 = findViewById(R.id.viewPager2)indicator = findViewById(R.id.indicator)}private fun initViewPager2() {val width = dp2px(10)for (i in mImgIds.indices) {val dot = View(this)dot.setBackgroundResource(R.drawable.dot_selector)val layoutParams = LinearLayout.LayoutParams(LinearLayout.LayoutParams(width, width))if (i != 0) {layoutParams.leftMargin = width} else {dot.isSelected = true}indicator.addView(dot, layoutParams)}viewPager2.adapter = ViewPager2Adapter(this, mImgIds)//设置监听viewPager2.registerOnPageChangeCallback(object : ViewPager2.OnPageChangeCallback() {override fun onPageScrolled(position: Int,positionOffset: Float,positionOffsetPixels: Int) {indicator.forEachIndexed { index, view ->view.isSelected = index == position}}})}
}

class ViewPager2Adapter(private val context: Context, private val mImgIds: IntArray) :RecyclerView.Adapter<ViewPager2Adapter.MyViewHolder>() {private var inflater: LayoutInflater = LayoutInflater.from(context)override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {return MyViewHolder(inflater.inflate(R.layout.item_image_view, parent, false))}override fun onBindViewHolder(holder: MyViewHolder, position: Int) {holder.imageView.setImageResource(mImgIds[position])}override fun getItemCount(): Int {return mImgIds.size}class MyViewHolder(private val itemView: View) : RecyclerView.ViewHolder(itemView) {public val imageView: ImageView = itemView as ImageView}
}

ViewPager2+TabLayout+Fragment

class TabActivity : BaseActivity() {private lateinit var tabLayout: TabLayoutprivate lateinit var viewPager2: ViewPager2private val titles = arrayOf("one", "two", "three", "four", "five", "six", "seven", "eight")private val fragmentList = arrayListOf<TextFragment>().apply {titles.forEachIndexed { index, s ->add(TextFragment.newInstance(s))}}companion object {fun start(context: Context) {val intent = Intent(context, TabActivity::class.java).apply {putExtra(KEY_TITLE, "ViewPager2+TabLayout+Fragment")}context.startActivity(intent)}}override fun onCreate(savedInstanceState: Bundle?) {super.onCreate(savedInstanceState)setContentView(R.layout.activity_tab)initView()// offscreenPageLimit默认不开启预加载// offscreenPageLimit设置为1表示缓存前一页，预加载下一页，包含当前页一共三页viewPager2.offscreenPageLimit = 1viewPager2.adapter = TabAdapter(this, fragmentList)TabLayoutMediator(tabLayout,viewPager2,object : TabLayoutMediator.TabConfigurationStrategy {override fun onConfigureTab(tab: TabLayout.Tab, position: Int) {tab.text = titles[position]}}).attach()}private fun initView() {tabLayout = findViewById(R.id.tabLayout)viewPager2 = findViewById(R.id.viewPager2)}
}

class TabAdapter(fragmentActivity: FragmentActivity,private val fragmentList: ArrayList<TextFragment>
) : FragmentStateAdapter(fragmentActivity) {override fun getItemCount(): Int = fragmentList.sizeoverride fun createFragment(position: Int): Fragment {return fragmentList[position]}
}

代码下载

Android ViewPager2总结相关推荐

Android - ViewPager2
文章目录 1. 效果 1. 添加ViewPager2控件 2. MainActivity.java中添加ViewPager2 3. 创建ViewPager中的页面 4. 添加ViewPagerAdap ...
Android - ViewPager2 Fragment
文章目录 1. 效果 2. 添加ViewPager2控件 3. 添加Fragment页面 4. 添加FragmentStateAdapter类的继承类 5. 添加ViewPager2的逻辑 6. 示例 ...
Android ViewPager2 真的香么？
Google 前段时间出了新品 ViewPager2,据说意在替代旧版 ViewPager,功能更强大使用更方便:真的这么香么,小菜尝试学习一下! 优势支持 RTL 布局,稍后介绍: 支持垂直方向切 ...
Android viewpager2 + indicator 实现页面滑动
在build.gradle里面添加依赖 implementation 'com.tbuonomo:dotsindicator:4.2'implementation 'androidx.viewpage ...
Android ViewPager2自定义页面切换动画
默认切换动画 MainActivity override fun onCreate(savedInstanceState: Bundle?) {super.onCreate(savedInstance ...
Android viewpager2实现翻页效果
为什么要实现翻页效果?减少用户的操作 viewpager2是基于recyclerview实现的,自带懒加载功能 viewpager2是对recyclerview的封装要实现下面这个效果 viewpa ...
android viewpager2,viewpager2原理和使用
近期google官网上更新了viewpager2, 支持垂直滚动, 重写之前的viewpager. 1.原理: viewpager2 内部实现原理是使用recycleview加LinearLayout ...
Android viewPager2 + fragment 模拟微信首页2(滑动页面标签同步变化,点击标签滑动页面)
可以实现的方式:BottomNavigationView 这里我们不使用BottomNavigationView,手动来写代码先看一下效果 fragment + viewPager2模拟微信首页2( ...
android viewpager2,Android-ViewPager2的使用
一.ViewPager2的变化 ViewPager2是用来替换ViewPager的,ViewPager2是final修饰的,直接继承ViewGroup,其内部是使用RecyclerView,ViewP ...

Android ViewPager2总结

文章目录

ViewPager2总结

概述

常用API

ViewPager2基本使用

ViewPager2+TabLayout+Fragment

代码下载

Android ViewPager2总结相关推荐

最新文章

热门文章