Fix crashing when changing theme

app/build.gradle

@@ -99,6 +99,11 @@ android {
     kapt {
         generateStubs = true
     }
+    kotlin {
+        experimental {
+            coroutines "enable"
+        }
+    }
 
 }
 
@@ -168,6 +173,9 @@ dependencies {
     def kotlin_coroutines_version = "1.3.3"
     implementation "org.jetbrains.kotlinx:kotlinx-coroutines-core:$kotlin_coroutines_version"
     implementation "org.jetbrains.kotlinx:kotlinx-coroutines-android:$kotlin_coroutines_version"
+    def arch_version = '2.2.0'
+    implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:$arch_version"
+    implementation "androidx.lifecycle:lifecycle-runtime-ktx:$arch_version"
 
     implementation 'org.eclipse.mylyn.github:org.eclipse.egit.github.core:3.4.0.201406110918-r'
 
@@ -184,4 +192,6 @@ dependencies {
     def dagger_version = "2.23.1"
     implementation "com.google.dagger:dagger:$dagger_version"
     kapt "com.google.dagger:dagger-compiler:$dagger_version"
+
+    implementation 'com.github.ologe:scroll-helper:1.1.5'
 }

app/src/main/java/code/name/monkey/retromusic/adapter/GenreAdapter.kt

@@ -4,8 +4,10 @@ import android.app.Activity
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
-import androidx.recyclerview.widget.RecyclerView
+import androidx.recyclerview.widget.DiffUtil
+import androidx.recyclerview.widget.ListAdapter
 import code.name.monkey.retromusic.R
+import code.name.monkey.retromusic.adapter.GenreAdapter.ViewHolder
 import code.name.monkey.retromusic.adapter.base.MediaEntryViewHolder
 import code.name.monkey.retromusic.model.Genre
 import code.name.monkey.retromusic.util.NavigationUtil
@@ -19,7 +21,7 @@ class GenreAdapter(
     private val activity: Activity,
     var dataSet: List<Genre>,
     private val mItemLayoutRes: Int
-) : RecyclerView.Adapter<GenreAdapter.ViewHolder>() {
+) : ListAdapter<Genre, ViewHolder>(GenreDiffCallback()) {
 
 
     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
@@ -54,3 +56,19 @@ class GenreAdapter(
         }
     }
 }
+
+/**
+ * Callback for calculating the diff between two non-null items in a list.
+ *
+ * Used by ListAdapter to calculate the minimum number of changes between and old list and a new
+ * list that's been passed to `submitList`.
+ */
+class GenreDiffCallback : DiffUtil.ItemCallback<Genre>() {
+    override fun areItemsTheSame(oldItem: Genre, newItem: Genre): Boolean {
+        return oldItem.id == newItem.id
+    }
+
+    override fun areContentsTheSame(oldItem: Genre, newItem: Genre): Boolean {
+        return oldItem == newItem
+    }
+}

app/src/main/java/code/name/monkey/retromusic/fragments/mainactivity/BannerHomeFragment.kt

@@ -20,6 +20,7 @@ import android.util.DisplayMetrics
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
+import androidx.lifecycle.lifecycleScope
 import androidx.recyclerview.widget.LinearLayoutManager
 import code.name.monkey.retromusic.App
 import code.name.monkey.retromusic.Constants
@@ -44,6 +45,8 @@ import com.bumptech.glide.load.engine.DiskCacheStrategy
 import kotlinx.android.synthetic.main.abs_playlists.*
 import kotlinx.android.synthetic.main.fragment_banner_home.*
 import kotlinx.android.synthetic.main.home_content.*
+import kotlinx.coroutines.async
+import kotlinx.coroutines.launch
 import java.io.File
 import java.util.*
 import javax.inject.Inject
@@ -119,7 +122,10 @@ class BannerHomeFragment : AbsMainActivityFragment(), MainActivityFragmentCallba
         }
 
         actionShuffle.setOnClickListener {
-            MusicPlayerRemote.openAndShuffleQueue(SongLoader.getAllSongs(requireActivity()), true)
+            lifecycleScope.launch {
+                val songs = async { SongLoader.getAllSongs(requireContext()) }
+                MusicPlayerRemote.openAndShuffleQueue(songs.await(), true)
+            }
         }
 
         history.setOnClickListener {

app/src/main/java/code/name/monkey/retromusic/fragments/settings/ThemeSettingsFragment.kt

@@ -16,7 +16,6 @@ package code.name.monkey.retromusic.fragments.settings
 
 import android.os.Build
 import android.os.Bundle
-import android.os.Handler
 import androidx.preference.Preference
 import androidx.preference.TwoStatePreference
 import code.name.monkey.appthemehelper.ACCENT_COLORS
@@ -54,9 +53,7 @@ class ThemeSettingsFragment : AbsSettingsFragment() {
                     requireActivity().setTheme(PreferenceUtil.getThemeResFromPrefValue(theme))
                     DynamicShortcutManager(requireContext()).updateDynamicShortcuts()
                 }
-                Handler().postDelayed({
+                requireActivity().recreate()
-                    requireActivity().recreate()
-                }, 400)
                 true
             }
         }
@@ -78,9 +75,7 @@ class ThemeSettingsFragment : AbsSettingsFragment() {
                     ThemeStore.editTheme(requireContext()).accentColor(color).commit()
                     if (VersionUtils.hasNougatMR())
                         DynamicShortcutManager(requireContext()).updateDynamicShortcuts()
-                    Handler().postDelayed({
+                    requireActivity().recreate()
-                        requireActivity().recreate()
-                    }, 400)
                 }
             }
             return@setOnPreferenceClickListener true
@@ -96,9 +91,7 @@ class ThemeSettingsFragment : AbsSettingsFragment() {
                 requireActivity().setTheme(PreferenceUtil.getThemeResFromPrefValue("black"))
                 DynamicShortcutManager(requireContext()).updateDynamicShortcuts()
             }
-            Handler().postDelayed({
+            requireActivity().recreate()
-                requireActivity().recreate()
-            }, 400)
             true
         }
 
@@ -109,9 +102,7 @@ class ThemeSettingsFragment : AbsSettingsFragment() {
             ThemeStore.prefs(requireContext()).edit().putBoolean("desaturated_color", desaturated)
                 .apply()
             PreferenceUtil.getInstance(requireContext()).setDesaturatedColor(desaturated)
-            Handler().postDelayed({
+            requireActivity().recreate()
-                requireActivity().recreate()
-            }, 400)
             true
         }
 

app/src/main/java/code/name/monkey/retromusic/util/AppExecutors.kt

@@ -0,0 +1,16 @@
+package code.name.monkey.retromusic.util
+
+import kotlinx.coroutines.CoroutineDispatcher
+import kotlinx.coroutines.Dispatchers
+
+const val THREAD_COUNT = 3
+
+/**
+ * Global executor pools for the whole application.
+ *
+ * Grouping tasks like this avoids the effects of task starvation (e.g. disk reads don't wait behind
+ * webservice requests).
+ */
+open class AppExecutors constructor(
+    val ioContext: CoroutineDispatcher = Dispatchers.IO
+)

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

@@ -97,7 +97,8 @@
                     app:retroCornerSize="36dp"
                     app:srcCompat="@drawable/ic_person_flat"
                     app:strokeColor="?attr/colorSurface"
-                    app:strokeWidth="2dp" />
+                    app:strokeWidth="2dp"
+                    tools:src="@tools:sample/avatars" />
 
                 <androidx.appcompat.widget.AppCompatImageView
                     android:layout_width="wrap_content"