Revert "Update to ViewPager2/FragmentStateAdapter to fix deprecation warnings."

This reverts commit 35915b1100.

src/musikdroid/app/build.gradle

@@ -23,6 +23,11 @@ android {
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
     }
 
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+
     buildTypes {
         release {
             minifyEnabled false
@@ -88,7 +93,6 @@ dependencies {
 
     implementation 'androidx.appcompat:appcompat:1.5.1'
     implementation 'androidx.recyclerview:recyclerview:1.2.1'
-    implementation 'androidx.viewpager2:viewpager2:1.1.0-beta01'
     implementation 'com.google.android.material:material:1.8.0-alpha02'
     implementation 'androidx.media:media:1.6.0'
 

src/musikdroid/app/src/main/java/io/casey/musikcube/remote/ui/browse/adapter/BrowseFragmentAdapter.kt

@@ -1,8 +1,10 @@
 package io.casey.musikcube.remote.ui.browse.adapter
 
 import android.content.Context
+import android.view.ViewGroup
 import androidx.fragment.app.Fragment
-import androidx.viewpager2.adapter.FragmentStateAdapter
+import androidx.fragment.app.FragmentManager
+import androidx.fragment.app.FragmentPagerAdapter
 import io.casey.musikcube.remote.R
 import io.casey.musikcube.remote.service.playback.impl.remote.Metadata
 import io.casey.musikcube.remote.ui.albums.fragment.AlbumBrowseFragment
@@ -17,9 +19,9 @@ import io.casey.musikcube.remote.ui.tracks.fragment.TrackListFragment
 
 class BrowseFragmentAdapter(private val context: Context,
                             private val playback: PlaybackMixin,
-                            fragment: Fragment,
+                            fm: FragmentManager,
                             private val containerId: Int = -1)
-    : FragmentStateAdapter(fragment)
+    : FragmentPagerAdapter(fm, BEHAVIOR_RESUME_ONLY_CURRENT_FRAGMENT)
 {
     private val fragments = mutableMapOf<Int, Fragment>()
 
@@ -50,16 +52,7 @@ class BrowseFragmentAdapter(private val context: Context,
             else -> 0
         }
 
-    fun getPageTitle(position: Int): CharSequence =
-        context.getString(when (position) {
-            0 -> R.string.button_artists
-            1 -> R.string.button_albums
-            2 -> R.string.button_tracks
-            3 -> R.string.button_playlists
-            else -> R.string.button_offline
-        })
-
-    override fun createFragment(index: Int): Fragment {
+    override fun getItem(index: Int): Fragment {
         val fragment: BaseFragment = when (index) {
             0 -> CategoryBrowseFragment.create(
                 CategoryBrowseFragment.arguments(context, Metadata.Category.ALBUM_ARTIST))
@@ -70,14 +63,27 @@ class BrowseFragmentAdapter(private val context: Context,
             else -> TrackListFragment.create(
                 TrackListFragment.arguments(context, Metadata.Category.OFFLINE))
         }
-        fragment.pushTo(this.containerId)
-        (fragment as? IFilterable)?.setFilter(filter)
-        onFragmentInstantiated?.invoke(index)
-        fragments[index] = fragment
-        return fragment
+        return fragment.pushTo(this.containerId)
     }
 
-    override fun getItemCount(): Int {
+    override fun getPageTitle(position: Int): CharSequence =
+        context.getString(when (position) {
+            0 -> R.string.button_artists
+            1 -> R.string.button_albums
+            2 -> R.string.button_tracks
+            3 -> R.string.button_playlists
+            else -> R.string.button_offline
+        })
+
+    override fun getCount(): Int {
         return if (playback.streaming) 5 else 4 /* hide "offline" for remote playback */
     }
+
+    override fun instantiateItem(container: ViewGroup, position: Int): Any {
+        val result = super.instantiateItem(container, position)
+        fragments[position] = result as Fragment
+        (result as? IFilterable)?.setFilter(filter)
+        onFragmentInstantiated?.invoke(position)
+        return result
+    }
 }

src/musikdroid/app/src/main/java/io/casey/musikcube/remote/ui/browse/fragment/BrowseFragment.kt

@@ -4,10 +4,9 @@ import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
-import androidx.viewpager2.widget.ViewPager2
+import androidx.viewpager.widget.ViewPager
 import com.google.android.material.floatingactionbutton.FloatingActionButton
 import com.google.android.material.tabs.TabLayout
-import com.google.android.material.tabs.TabLayoutMediator
 import io.casey.musikcube.remote.R
 import io.casey.musikcube.remote.ui.browse.adapter.BrowseFragmentAdapter
 import io.casey.musikcube.remote.ui.browse.constant.Browse
@@ -33,7 +32,7 @@ class BrowseFragment: BaseFragment(), ITransportObserver, IFilterable, ITitlePro
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? =
         inflater.inflate(R.layout.browse_fragment, container, false).apply {
             val fab = findViewById<FloatingActionButton>(R.id.fab)
-            val pager = findViewById<ViewPager2>(R.id.view_pager)
+            val pager = findViewById<ViewPager>(R.id.view_pager)
             val tabs = findViewById<TabLayout>(R.id.tab_layout)
 
             val showFabIfNecessary = { pos: Int ->
@@ -57,7 +56,7 @@ class BrowseFragment: BaseFragment(), ITransportObserver, IFilterable, ITitlePro
             adapter = BrowseFragmentAdapter(
                 appCompatActivity,
                 playback,
-                this@BrowseFragment,
+                childFragmentManager,
                 R.id.content_container)
 
             adapter.onFragmentInstantiated = { pos ->
@@ -68,26 +67,23 @@ class BrowseFragment: BaseFragment(), ITransportObserver, IFilterable, ITitlePro
 
             pager.isSaveEnabled = false
             pager.adapter = adapter
-            pager.offscreenPageLimit = adapter.itemCount
+            pager.currentItem = adapter.indexOf(extras.getString(Browse.Extras.INITIAL_CATEGORY_TYPE))
 
-            pager.registerOnPageChangeCallback(object: ViewPager2.OnPageChangeCallback() {
-                override fun onPageSelected(position: Int) {
-                    showFabIfNecessary(position)
+            tabs.setupWithViewPager(pager)
+
+            pager.addOnPageChangeListener(object: ViewPager.OnPageChangeListener {
+                override fun onPageScrollStateChanged(state: Int) {
+                }
+
+                override fun onPageScrolled(pos: Int, offset: Float, offsetPixels: Int) {
+                }
+
+                override fun onPageSelected(pos: Int) {
+                    showFabIfNecessary(pos)
                 }
             })
 
-            TabLayoutMediator(tabs, pager, true) { tab, position ->
-                tab.text = adapter.getPageTitle(position)
-            }.attach()
-
-            val initialIndex = adapter.indexOf(
-                extras.getString(Browse.Extras.INITIAL_CATEGORY_TYPE))
-
-            pager.setCurrentItem(initialIndex, false)
-
-            pager.post {
-                showFabIfNecessary(pager.currentItem)
-            }
+            showFabIfNecessary(pager.currentItem)
         }
 
     override fun onTransportChanged() =

src/musikdroid/app/src/main/res/layout/browse_fragment.xml

@@ -27,7 +27,7 @@
 
     </com.google.android.material.appbar.AppBarLayout>
 
-    <androidx.viewpager2.widget.ViewPager2
+    <androidx.viewpager.widget.ViewPager
         android:id="@+id/view_pager"
         android:layout_width="match_parent"
         android:layout_height="match_parent"