viewPager2 3层嵌套有问题,书架换回viewPager

app/src/main/java/io/legado/app/ui/main/MainActivity.kt

@@ -1,12 +1,16 @@
+@file:Suppress("DEPRECATION")
+
 package io.legado.app.ui.main
 
 import android.os.Bundle
 import android.view.KeyEvent
 import android.view.MenuItem
+import android.view.ViewGroup
 import androidx.activity.viewModels
 import androidx.fragment.app.Fragment
-import androidx.viewpager2.adapter.FragmentStateAdapter
+import androidx.fragment.app.FragmentManager
-import androidx.viewpager2.widget.ViewPager2
+import androidx.fragment.app.FragmentStatePagerAdapter
+import androidx.viewpager.widget.ViewPager
 import com.google.android.material.bottomnavigation.BottomNavigationView
 import io.legado.app.BuildConfig
 import io.legado.app.R
@@ -40,7 +44,7 @@ class MainActivity : VMBaseActivity<ActivityMainBinding, MainViewModel>(),
     private var bookshelfReselected: Long = 0
     private var exploreReselected: Long = 0
     private var pagePosition = 0
-    private val fragmentMap = hashMapOf<Long, Fragment>()
+    private val fragmentMap = hashMapOf<Int, Fragment>()
     private var bottomMenuCount = 2
     private val realPositions = arrayOf(0, 1, 2, 3)
 
@@ -54,8 +58,8 @@ class MainActivity : VMBaseActivity<ActivityMainBinding, MainViewModel>(),
             ATH.applyEdgeEffectColor(viewPagerMain)
             ATH.applyBottomNavigationColor(bottomNavigationView)
             viewPagerMain.offscreenPageLimit = 3
-            viewPagerMain.adapter = TabFragmentPageAdapter()
+            viewPagerMain.adapter = TabFragmentPageAdapter(supportFragmentManager)
-            viewPagerMain.registerOnPageChangeCallback(PageChangeCallback())
+            viewPagerMain.addOnPageChangeListener(PageChangeCallback())
             bottomNavigationView.elevation =
                 if (AppConfig.elevation < 0) elevation else AppConfig.elevation.toFloat()
             bottomNavigationView.setOnNavigationItemSelectedListener(this@MainActivity)
@@ -110,10 +114,6 @@ class MainActivity : VMBaseActivity<ActivityMainBinding, MainViewModel>(),
         }
     }
 
-    fun getViewPager(): ViewPager2 {
-        return binding.viewPagerMain
-    }
-
     private fun upVersion() {
         if (LocalConfig.versionCode != appInfo.versionCode) {
             LocalConfig.versionCode = appInfo.versionCode
@@ -210,38 +210,44 @@ class MainActivity : VMBaseActivity<ActivityMainBinding, MainViewModel>(),
         }
     }
 
-    private inner class PageChangeCallback : ViewPager2.OnPageChangeCallback() {
+    private inner class PageChangeCallback : ViewPager.SimpleOnPageChangeListener() {
+
         override fun onPageSelected(position: Int) {
             pagePosition = position
             binding.bottomNavigationView.menu
                 .getItem(realPositions[position]).isChecked = true
         }
+
     }
 
-    private inner class TabFragmentPageAdapter :
+    @Suppress("DEPRECATION")
-        FragmentStateAdapter(this) {
+    private inner class TabFragmentPageAdapter(fm: FragmentManager) :
+        FragmentStatePagerAdapter(fm, BEHAVIOR_RESUME_ONLY_CURRENT_FRAGMENT) {
 
-        override fun containsItem(itemId: Long): Boolean {
+        private fun getId(position: Int): Int {
-            return fragmentMap.containsKey(itemId)
+            return realPositions[position]
         }
 
-        override fun getItemCount(): Int {
+        override fun getItemPosition(`object`: Any): Int {
-            return bottomMenuCount
+            return POSITION_NONE
         }
 
-        override fun getItemId(position: Int): Long {
+        override fun getItem(position: Int): Fragment {
-            return realPositions[position].toLong()
+            return when (getId(position)) {
-        }
+                0 -> BookshelfFragment()
-
+                1 -> ExploreFragment()
-        override fun createFragment(position: Int): Fragment {
+                2 -> RssFragment()
-            val id = getItemId(position)
-            val fragment = when (id) {
-                0L -> BookshelfFragment()
-                1L -> ExploreFragment()
-                2L -> RssFragment()
                 else -> MyFragment()
             }
-            fragmentMap[id] = fragment
+        }
+
+        override fun getCount(): Int {
+            return bottomMenuCount
+        }
+
+        override fun instantiateItem(container: ViewGroup, position: Int): Any {
+            val fragment = super.instantiateItem(container, position) as Fragment
+            fragmentMap[getId(position)] = fragment
             return fragment
         }
 

app/src/main/java/io/legado/app/ui/main/bookshelf/BookshelfFragment.kt

@@ -5,14 +5,11 @@ import android.os.Bundle
 import android.view.Menu
 import android.view.MenuItem
 import android.view.View
+import android.view.ViewGroup
 import androidx.appcompat.widget.SearchView
-import androidx.fragment.app.Fragment
+import androidx.fragment.app.*
-import androidx.fragment.app.activityViewModels
-import androidx.fragment.app.viewModels
 import androidx.lifecycle.LiveData
-import androidx.viewpager2.adapter.FragmentStateAdapter
 import com.google.android.material.tabs.TabLayout
-import com.google.android.material.tabs.TabLayoutMediator
 import io.legado.app.R
 import io.legado.app.base.VMBaseFragment
 import io.legado.app.constant.AppConst
@@ -22,7 +19,6 @@ import io.legado.app.data.entities.BookGroup
 import io.legado.app.databinding.DialogBookshelfConfigBinding
 import io.legado.app.databinding.DialogEditTextBinding
 import io.legado.app.databinding.FragmentBookshelfBinding
-import io.legado.app.help.AppConfig
 import io.legado.app.lib.dialogs.alert
 import io.legado.app.lib.theme.ATH
 import io.legado.app.lib.theme.accentColor
@@ -48,7 +44,7 @@ class BookshelfFragment : VMBaseFragment<BookshelfViewModel>(R.layout.fragment_b
     private val binding by viewBinding(FragmentBookshelfBinding::bind)
     override val viewModel: BookshelfViewModel by viewModels()
     private val activityViewModel: MainViewModel by activityViewModels()
-    private lateinit var adapter: FragmentStateAdapter
+    private lateinit var adapter: FragmentStatePagerAdapter
     private lateinit var tabLayout: TabLayout
     private var bookGroupLiveData: LiveData<List<BookGroup>>? = null
     private val bookGroups = mutableListOf<BookGroup>()
@@ -109,12 +105,10 @@ class BookshelfFragment : VMBaseFragment<BookshelfViewModel>(R.layout.fragment_b
         tabLayout.isTabIndicatorFullWidth = false
         tabLayout.tabMode = TabLayout.MODE_SCROLLABLE
         tabLayout.setSelectedTabIndicatorColor(requireContext().accentColor)
+        tabLayout.setupWithViewPager(binding.viewPagerBookshelf)
         binding.viewPagerBookshelf.offscreenPageLimit = 1
-        adapter = TabFragmentPageAdapter()
+        adapter = TabFragmentPageAdapter(childFragmentManager)
         binding.viewPagerBookshelf.adapter = adapter
-        TabLayoutMediator(tabLayout, binding.viewPagerBookshelf) { tab, i ->
-            tab.text = bookGroups[i].groupName
-        }.attach()
     }
 
     private fun initBookGroupData() {
@@ -169,7 +163,6 @@ class BookshelfFragment : VMBaseFragment<BookshelfViewModel>(R.layout.fragment_b
                     .apply {
                         rgLayout.checkByIndex(bookshelfLayout)
                         rgSort.checkByIndex(bookshelfSort)
-                        swShowUnread.isChecked = AppConfig.showUnread
                     }
             customView { alertBinding.root }
             okButton {
@@ -183,10 +176,6 @@ class BookshelfFragment : VMBaseFragment<BookshelfViewModel>(R.layout.fragment_b
                         putPrefInt(PreferKey.bookshelfSort, rgSort.getCheckedIndex())
                         changed = true
                     }
-                    if (AppConfig.showUnread != swShowUnread.isChecked) {
-                        AppConfig.showUnread = swShowUnread.isChecked
-                        changed = true
-                    }
                     if (changed) {
                         activity?.recreate()
                     }
@@ -249,25 +238,29 @@ class BookshelfFragment : VMBaseFragment<BookshelfViewModel>(R.layout.fragment_b
         }.show()
     }
 
-    private inner class TabFragmentPageAdapter :
+    private inner class TabFragmentPageAdapter(fm: FragmentManager) :
-        FragmentStateAdapter(this) {
+        FragmentStatePagerAdapter(fm, BEHAVIOR_RESUME_ONLY_CURRENT_FRAGMENT) {
 
-        override fun getItemId(position: Int): Long {
+        override fun getPageTitle(position: Int): CharSequence {
-            val group = bookGroups[position]
+            return bookGroups[position].groupName
-            return group.groupId
         }
 
-        override fun containsItem(itemId: Long): Boolean {
+        override fun getItemPosition(`object`: Any): Int {
-            return fragmentMap.containsKey(itemId)
+            return POSITION_NONE
+        }
+
+        override fun getItem(position: Int): Fragment {
+            val group = bookGroups[position]
+            return BooksFragment.newInstance(position, group.groupId)
         }
 
-        override fun getItemCount(): Int {
+        override fun getCount(): Int {
             return bookGroups.size
         }
 
-        override fun createFragment(position: Int): Fragment {
+        override fun instantiateItem(container: ViewGroup, position: Int): Any {
+            val fragment = super.instantiateItem(container, position) as BooksFragment
             val group = bookGroups[position]
-            val fragment = BooksFragment.newInstance(position, group.groupId)
             fragmentMap[group.groupId] = fragment
             return fragment
         }

app/src/main/java/io/legado/app/ui/main/bookshelf/RootView.kt

@@ -1,82 +0,0 @@
-package io.legado.app.ui.main.bookshelf
-
-import android.content.Context
-import android.gesture.GestureOverlayView.ORIENTATION_HORIZONTAL
-import android.util.AttributeSet
-import android.view.MotionEvent
-import android.view.View
-import android.view.ViewConfiguration
-import android.widget.LinearLayout
-import androidx.viewpager2.widget.ViewPager2
-import io.legado.app.R
-import io.legado.app.ui.main.MainActivity
-import io.legado.app.utils.activity
-import kotlin.math.absoluteValue
-import kotlin.math.sign
-
-class RootView : LinearLayout {
-
-    constructor(context: Context) : super(context)
-    constructor(context: Context, attrs: AttributeSet?) : super(context, attrs)
-
-    private val touchSlop = ViewConfiguration.get(context).scaledTouchSlop
-    private var initialX = 0f
-    private var initialY = 0f
-
-    private val parentViewPager: ViewPager2?
-        get() = (activity as? MainActivity)?.getViewPager()
-    private val childViewPager: View?
-        get() = findViewById(R.id.view_pager_bookshelf)
-
-    private fun canChildScroll(orientation: Int, delta: Float): Boolean {
-        val direction = -delta.sign.toInt()
-        return when (orientation) {
-            0 -> childViewPager?.canScrollHorizontally(direction) ?: false
-            1 -> childViewPager?.canScrollVertically(direction) ?: false
-            else -> throw IllegalArgumentException()
-        }
-    }
-
-    override fun onInterceptTouchEvent(e: MotionEvent): Boolean {
-        handleInterceptTouchEvent(e)
-        return super.onInterceptTouchEvent(e)
-    }
-
-    private fun handleInterceptTouchEvent(e: MotionEvent) {
-        val orientation = parentViewPager?.orientation ?: return
-        // Early return if child can't scroll in same direction as parent
-        if (!canChildScroll(orientation, -1f) && !canChildScroll(orientation, 1f)) {
-            return
-        }
-
-        if (e.action == MotionEvent.ACTION_DOWN) {
-            initialX = e.x
-            initialY = e.y
-            parent.requestDisallowInterceptTouchEvent(true)
-        } else if (e.action == MotionEvent.ACTION_MOVE) {
-            val dx = e.x - initialX
-            val dy = e.y - initialY
-            val isVpHorizontal = orientation == ORIENTATION_HORIZONTAL
-            // assuming ViewPager2 touch-slop is 2x touch-slop of child
-            val scaledDx = dx.absoluteValue * if (isVpHorizontal) .5f else 1f
-            val scaledDy = dy.absoluteValue * if (isVpHorizontal) 1f else .5f
-
-            if (scaledDx > touchSlop || scaledDy > touchSlop) {
-
-                if (isVpHorizontal == (scaledDy > scaledDx)) {
-                    // Gesture is perpendicular, allow all parents to intercept
-                    parent.requestDisallowInterceptTouchEvent(false)
-                } else {
-                    // Gesture is parallel, query child if movement in that direction is possible
-                    if (canChildScroll(orientation, if (isVpHorizontal) dx else dy)) {
-                        // Child can scroll, disallow all parents to intercept
-                        parent.requestDisallowInterceptTouchEvent(true)
-                    } else {
-                        // Child cannot scroll, allow all parents to intercept
-                        parent.requestDisallowInterceptTouchEvent(false)
-                    }
-                }
-            }
-        }
-    }
-}

app/src/main/java/io/legado/app/ui/main/bookshelf1/BookshelfFragment1.kt

@@ -48,7 +48,7 @@ import kotlin.math.max
 /**
  * 书架界面
  */
-class BookshelfFragment : VMBaseFragment<BookshelfViewModel>(R.layout.fragment_bookshelf1),
+class BookshelfFragment1 : VMBaseFragment<BookshelfViewModel>(R.layout.fragment_bookshelf1),
     SearchView.OnQueryTextListener,
     BaseBooksAdapter.CallBack {
 

app/src/main/res/layout/activity_main.xml

@@ -5,7 +5,7 @@
     android:layout_height="match_parent"
     android:orientation="vertical">
 
-    <androidx.viewpager2.widget.ViewPager2
+    <androidx.viewpager.widget.ViewPager
         android:id="@+id/view_pager_main"
         android:layout_width="match_parent"
         android:layout_height="0dp"

app/src/main/res/layout/fragment_bookshelf.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<io.legado.app.ui.main.bookshelf.RootView xmlns:android="http://schemas.android.com/apk/res/android"
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
@@ -13,9 +13,9 @@
         app:contentLayout="@layout/view_tab_layout_min"
         app:title="@string/bookshelf" />
 
-    <androidx.viewpager2.widget.ViewPager2
+    <androidx.viewpager.widget.ViewPager
         android:id="@+id/view_pager_bookshelf"
         android:layout_width="match_parent"
         android:layout_height="match_parent" />
 
-</io.legado.app.ui.main.bookshelf.RootView>
+</LinearLayout>