Load event app lists asynchronously

app/src/main/java/se/ajpanton/notificationlog/EventSettingsFragment.kt

@@ -1,61 +1,67 @@
 package se.ajpanton.notificationlog
 
 import android.os.Bundle
+import android.text.SpannableString
+import android.text.Spanned
+import android.text.style.StyleSpan
+import android.text.style.UnderlineSpan
 import android.view.MotionEvent
 import android.view.View
+import android.view.ViewGroup
 import android.widget.CheckBox
 import android.widget.LinearLayout
 import android.widget.TextView
 import androidx.annotation.StringRes
+import androidx.core.content.ContextCompat
 import androidx.fragment.app.Fragment
+import androidx.recyclerview.widget.LinearLayoutManager
+import androidx.recyclerview.widget.RecyclerView
+import se.ajpanton.notificationlog.capture.SeenApps
 import se.ajpanton.notificationlog.databinding.FragmentEventSettingsBinding
-import se.ajpanton.notificationlog.settings.AppRuleMode
-import se.ajpanton.notificationlog.settings.LoggingRuleStore
-import se.ajpanton.notificationlog.settings.LoggingType
 import se.ajpanton.notificationlog.settings.AppListItem
 import se.ajpanton.notificationlog.settings.AppListOrdering
+import se.ajpanton.notificationlog.settings.AppRuleMode
 import se.ajpanton.notificationlog.settings.ListedApp
-import se.ajpanton.notificationlog.capture.SeenApps
+import se.ajpanton.notificationlog.settings.LoggingRule
+import se.ajpanton.notificationlog.settings.LoggingRuleStore
+import se.ajpanton.notificationlog.settings.LoggingType
 
 class EventSettingsFragment : Fragment(R.layout.fragment_event_settings) {
     private var binding: FragmentEventSettingsBinding? = null
     private lateinit var type: LoggingType
     private lateinit var store: LoggingRuleStore
+    private lateinit var appAdapter: AppListAdapter
+    private var appLoadGeneration = 0
 
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         super.onViewCreated(view, savedInstanceState)
         binding = FragmentEventSettingsBinding.bind(view)
         type = requireArguments().getSerializable(ARG_TYPE, LoggingType::class.java)!!
         store = LoggingRuleStore(requireContext())
+        appAdapter = AppListAdapter(::setPackageSelected)
         binding!!.pageTitle.setText(requireArguments().getInt(ARG_TITLE))
+        binding!!.appList.layoutManager = LinearLayoutManager(requireContext())
+        binding!!.appList.adapter = appAdapter
+        binding!!.appListRefresh.setOnRefreshListener(::reloadAppList)
+        installBottomRefresh()
         bindRule()
-        binding!!.appListRefresh.setOnRefreshListener(::refreshAppList)
-        var touchStartY = 0f
-        val scroll = binding!!.appScroll
-        scroll.setOnTouchListener { _, event ->
-            when (event.actionMasked) {
-                MotionEvent.ACTION_DOWN -> touchStartY = event.y
-                MotionEvent.ACTION_UP -> {
-                    val atBottom = scroll.scrollY >= (scroll.getChildAt(0).height - scroll.height).coerceAtLeast(0)
-                    if (atBottom && event.y < touchStartY) {
-                        refreshAppList()
-                    }
-                }
-            }
-            false
-        }
     }
 
-    override fun onDestroyView() { binding = null; super.onDestroyView() }
+    override fun onDestroyView() {
+        appLoadGeneration++
+        binding = null
+        super.onDestroyView()
+    }
 
-    private fun refreshAppList() {
-        val currentBinding = binding ?: return
-        currentBinding.appListRefresh.isRefreshing = true
-        currentBinding.appListRefresh.post {
-            if (binding === currentBinding) {
-                reloadAppList()
-                currentBinding.appListRefresh.isRefreshing = false
+    private fun installBottomRefresh() {
+        val list = binding!!.appList
+        var touchStartY = 0f
+        list.setOnTouchListener { _, event ->
+            when (event.actionMasked) {
+                MotionEvent.ACTION_DOWN -> touchStartY = event.y
+                MotionEvent.ACTION_UP -> if (!list.canScrollVertically(1) && event.y < touchStartY) reloadAppList()
             }
+            false
         }
     }
 
@@ -75,75 +81,164 @@ class EventSettingsFragment : Fragment(R.layout.fragment_event_settings) {
         binding!!.seenFirstToggle.isEnabled = !rule.onlySeenApps
         binding!!.routineUpdatesToggle.visibility = if (type == LoggingType.EDITS) View.VISIBLE else View.GONE
         binding!!.routineUpdatesToggle.isChecked = rule.ignoreRoutineUpdates
-        updateRuleLabels()
+        updateRuleLabels(rule)
         binding!!.masterToggle.setOnCheckedChangeListener { _, checked -> save { copy(enabled = checked) } }
-        binding!!.appRuleToggle.setOnCheckedChangeListener { _, checked -> save { copy(appRuleMode = if (checked) AppRuleMode.WHITELIST else AppRuleMode.BLACKLIST) } }
+        binding!!.appRuleToggle.setOnCheckedChangeListener { _, checked ->
+            save { copy(appRuleMode = if (checked) AppRuleMode.WHITELIST else AppRuleMode.BLACKLIST) }
+        }
         binding!!.onlySeenToggle.setOnCheckedChangeListener { _, checked -> save { copy(onlySeenApps = checked) } }
         binding!!.seenFirstToggle.setOnCheckedChangeListener { _, checked -> save { copy(seenAppsFirst = checked) } }
         binding!!.routineUpdatesToggle.setOnCheckedChangeListener { _, checked -> save { copy(ignoreRoutineUpdates = checked) } }
         reloadAppList()
     }
 
-    private fun save(change: se.ajpanton.notificationlog.settings.LoggingRule.() -> se.ajpanton.notificationlog.settings.LoggingRule) {
+    private fun save(change: LoggingRule.() -> LoggingRule) {
         store.save(type, store.ruleFor(type).change())
         bindRule()
     }
 
-    private fun updateRuleLabels() {
-        val rule = store.ruleFor(type)
-        binding!!.appRuleToggle.text = if (rule.appRuleMode == AppRuleMode.WHITELIST) "Whitelist chosen" else "Blacklist chosen"
-        binding!!.onlySeenToggle.text = if (rule.onlySeenApps) "Show only seen apps" else "Show all apps"
+    private fun updateRuleLabels(rule: LoggingRule) {
+        binding!!.masterToggle.text = "Enable logging"
+        binding!!.appRuleToggle.text = modeLabel(rule.appRuleMode)
+        binding!!.onlySeenToggle.text = "Show only seen apps"
+        binding!!.seenFirstToggle.text = "Show seen apps first"
+    }
+
+    private fun modeLabel(mode: AppRuleMode): CharSequence {
+        val text = "Blacklist / Whitelist"
+        val selected = if (mode == AppRuleMode.BLACKLIST) "Blacklist" else "Whitelist"
+        val start = text.indexOf(selected)
+        return SpannableString(text).apply {
+            setSpan(StyleSpan(android.graphics.Typeface.BOLD), start, start + selected.length, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE)
+            setSpan(UnderlineSpan(), start, start + selected.length, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE)
+        }
     }
 
     private fun reloadAppList() {
-        val container = binding!!.appList
-        container.removeAllViews()
+        val currentBinding = binding ?: return
+        if (currentBinding.appListRefresh.isRefreshing) {
+            // A fresh swipe replaces the current snapshot; no live updates occur otherwise.
+        }
+        val generation = ++appLoadGeneration
+        currentBinding.appListLoading.visibility = View.VISIBLE
+        currentBinding.appListRefresh.isRefreshing = true
         val rule = store.ruleFor(type)
         val seen = SeenApps.snapshot()
-        val apps = requireContext().packageManager.getInstalledApplications(0)
-            .map { info ->
+        val context = requireContext().applicationContext
+        Thread {
+            val apps = context.packageManager.getInstalledApplications(0).map { info ->
                 ListedApp(
-                    label = requireContext().packageManager.getApplicationLabel(info).toString(),
+                    label = context.packageManager.getApplicationLabel(info).toString(),
                     packageName = info.packageName,
                     seen = info.packageName in seen,
                     selected = info.packageName in rule.selectedPackages,
                 )
             }
-        AppListOrdering.items(apps, rule.onlySeenApps, rule.seenAppsFirst).forEach { item ->
-            container.addView(if (item is AppListItem.App) appView(item.value) else separator())
-        }
-    }
-
-    private fun appView(row: ListedApp): View = LinearLayout(requireContext()).apply {
-        orientation = LinearLayout.HORIZONTAL
-        val checkbox = CheckBox(context).apply { isChecked = row.selected }
-        checkbox.setOnCheckedChangeListener { _, checked ->
-            val current = store.ruleFor(type)
-            val packages = current.selectedPackages.toMutableSet().apply {
-                if (checked) add(row.packageName) else remove(row.packageName)
+            val items = AppListOrdering.items(apps, rule.onlySeenApps, rule.seenAppsFirst)
+            activity?.runOnUiThread {
+                if (binding === currentBinding && generation == appLoadGeneration) {
+                    appAdapter.submit(items)
+                    currentBinding.appListLoading.visibility = View.GONE
+                    currentBinding.appListRefresh.isRefreshing = false
+                }
             }
-            store.save(type, current.copy(selectedPackages = packages))
-            // Deliberately do not reload: an unchecked unseen row must remain reachable.
-        }
-        addView(checkbox)
-        addView(LinearLayout(context).apply {
-            orientation = LinearLayout.VERTICAL
-            layoutParams = LinearLayout.LayoutParams(0, LinearLayout.LayoutParams.WRAP_CONTENT, 1f)
-            addView(TextView(context).apply { text = row.label; textSize = 16f; setTypeface(typeface, 1) })
-            addView(TextView(context).apply { text = row.packageName; textSize = 12f })
-        })
+        }.start()
     }
 
-    private fun separator() = View(requireContext()).apply {
-        layoutParams = LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, 1).apply { setMargins(0, 12, 0, 12) }
-        setBackgroundColor(0x33000000)
+    private fun setPackageSelected(packageName: String, selected: Boolean) {
+        val current = store.ruleFor(type)
+        val packages = current.selectedPackages.toMutableSet().apply {
+            if (selected) add(packageName) else remove(packageName)
+        }
+        store.save(type, current.copy(selectedPackages = packages))
+        // Do not reload: an unchecked unseen row remains visible until the next requested refresh.
+    }
+
+    private class AppListAdapter(
+        private val onSelectedChanged: (String, Boolean) -> Unit,
+    ) : RecyclerView.Adapter<RecyclerView.ViewHolder>() {
+        private var items: List<AppListItem> = emptyList()
+
+        fun submit(newItems: List<AppListItem>) {
+            items = newItems
+            notifyDataSetChanged()
+        }
+
+        override fun getItemViewType(position: Int): Int = if (items[position] is AppListItem.App) APP else SEPARATOR
+
+        override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder = if (viewType == APP) {
+            val row = LinearLayout(parent.context).apply {
+                orientation = LinearLayout.HORIZONTAL
+                setPadding(0, dp(parent, 4), 0, dp(parent, 4))
+            }
+            val checkbox = CheckBox(parent.context)
+            val textColumn = LinearLayout(parent.context).apply {
+                orientation = LinearLayout.VERTICAL
+                layoutParams = LinearLayout.LayoutParams(0, LinearLayout.LayoutParams.WRAP_CONTENT, 1f)
+            }
+            val label = TextView(parent.context).apply { textSize = 16f; setTypeface(typeface, android.graphics.Typeface.BOLD) }
+            val packageName = TextView(parent.context).apply { textSize = 12f }
+            textColumn.addView(label)
+            textColumn.addView(packageName)
+            row.addView(checkbox)
+            row.addView(textColumn)
+            AppHolder(row, checkbox, label, packageName)
+        } else {
+            val divider = View(parent.context).apply {
+                layoutParams = RecyclerView.LayoutParams(RecyclerView.LayoutParams.MATCH_PARENT, dp(parent, 1)).apply {
+                    setMargins(0, dp(parent, 12), 0, dp(parent, 12))
+                }
+                setBackgroundColor(ContextCompat.getColor(parent.context, android.R.color.darker_gray))
+            }
+            SeparatorHolder(divider)
+        }
+
+        override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
+            val item = items[position]
+            if (holder is AppHolder && item is AppListItem.App) {
+                val app = item.value
+                holder.label.text = app.label
+                holder.packageName.text = app.packageName
+                holder.checkbox.setOnCheckedChangeListener(null)
+                holder.checkbox.isChecked = app.selected
+                holder.checkbox.setOnCheckedChangeListener { _, checked ->
+                    onSelectedChanged(app.packageName, checked)
+                    items = items.map { current ->
+                        if (current is AppListItem.App && current.value.packageName == app.packageName) {
+                            AppListItem.App(current.value.copy(selected = checked))
+                        } else current
+                    }
+                }
+            }
+        }
+
+        override fun getItemCount(): Int = items.size
+
+        private class AppHolder(
+            view: View,
+            val checkbox: CheckBox,
+            val label: TextView,
+            val packageName: TextView,
+        ) : RecyclerView.ViewHolder(view)
+
+        private class SeparatorHolder(view: View) : RecyclerView.ViewHolder(view)
+
+        private companion object {
+            const val APP = 0
+            const val SEPARATOR = 1
+            fun dp(parent: ViewGroup, value: Int): Int = (value * parent.resources.displayMetrics.density).toInt()
+        }
     }
 
     companion object {
         private const val ARG_TITLE = "title"
         private const val ARG_TYPE = "type"
+
         fun newInstance(@StringRes title: Int, type: LoggingType) = EventSettingsFragment().apply {
-            arguments = Bundle().apply { putInt(ARG_TITLE, title); putSerializable(ARG_TYPE, type) }
+            arguments = Bundle().apply {
+                putInt(ARG_TITLE, title)
+                putSerializable(ARG_TYPE, type)
+            }
         }
     }
 }

app/src/main/java/se/ajpanton/notificationlog/settings/AppListOrdering.kt

@@ -11,14 +11,18 @@ object AppListOrdering {
         val apps = allApps.sortedWith(compareBy(String.CASE_INSENSITIVE_ORDER) { it.label })
         val shown = if (onlySeen) apps.filter { it.seen || it.selected } else apps
         val seen = shown.filter { it.seen }
-        val other = shown.filterNot { it.seen }
-        val separate = (onlySeen || seenAppsFirst) && seen.isNotEmpty() && other.isNotEmpty()
+        val selectedUnseen = shown.filter { !it.seen }
+        if (!seenAppsFirst || seen.isEmpty()) return shown.map(AppListItem::App)
         return buildList {
-            if (separate) {
-                seen.forEach { add(AppListItem.App(it)) }
-                add(AppListItem.Separator)
-                other.forEach { add(AppListItem.App(it)) }
+            seen.forEach { add(AppListItem.App(it)) }
+            if (onlySeen) {
+                if (selectedUnseen.isNotEmpty()) {
+                    add(AppListItem.Separator)
+                    selectedUnseen.forEach { add(AppListItem.App(it)) }
+                }
             } else {
+                add(AppListItem.Separator)
+                // The full alphabetical list intentionally repeats seen apps after its quick-access group.
                 shown.forEach { add(AppListItem.App(it)) }
             }
         }

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

@@ -1,12 +1,83 @@
 <?xml version="1.0" encoding="utf-8"?>
-<androidx.swiperefreshlayout.widget.SwipeRefreshLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/app_list_refresh" android:layout_width="match_parent" android:layout_height="match_parent"><ScrollView android:id="@+id/app_scroll" android:layout_width="match_parent" android:layout_height="match_parent">
- <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="vertical" android:padding="@dimen/page_padding">
-  <TextView android:id="@+id/page_title" android:layout_width="match_parent" android:layout_height="wrap_content" android:textAppearance="?attr/textAppearanceHeadline5" />
-  <com.google.android.material.switchmaterial.SwitchMaterial android:id="@+id/master_toggle" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginTop="24dp" android:text="Logging enabled" />
-  <com.google.android.material.switchmaterial.SwitchMaterial android:id="@+id/app_rule_toggle" android:layout_width="match_parent" android:layout_height="wrap_content" />
-  <com.google.android.material.switchmaterial.SwitchMaterial android:id="@+id/only_seen_toggle" android:layout_width="match_parent" android:layout_height="wrap_content" />
-  <com.google.android.material.switchmaterial.SwitchMaterial android:id="@+id/seen_first_toggle" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="Show seen apps at the top" />
-  <com.google.android.material.switchmaterial.SwitchMaterial android:id="@+id/routine_updates_toggle" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="Ignore routine updates" />
-  <LinearLayout android:id="@+id/app_list" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginTop="24dp" android:orientation="vertical" />
- </LinearLayout>
-</ScrollView></androidx.swiperefreshlayout.widget.SwipeRefreshLayout>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical"
+    android:padding="@dimen/page_padding">
+
+    <TextView
+        android:id="@+id/page_title"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:textAppearance="?attr/textAppearanceHeadline5" />
+
+    <com.google.android.material.switchmaterial.SwitchMaterial
+        android:id="@+id/master_toggle"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="24dp"
+        android:text="Enable logging" />
+
+    <com.google.android.material.switchmaterial.SwitchMaterial
+        android:id="@+id/app_rule_toggle"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content" />
+
+    <com.google.android.material.switchmaterial.SwitchMaterial
+        android:id="@+id/only_seen_toggle"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="Show only seen apps" />
+
+    <com.google.android.material.switchmaterial.SwitchMaterial
+        android:id="@+id/seen_first_toggle"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="Show seen apps first" />
+
+    <com.google.android.material.switchmaterial.SwitchMaterial
+        android:id="@+id/routine_updates_toggle"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="Ignore routine updates" />
+
+    <FrameLayout
+        android:layout_width="match_parent"
+        android:layout_height="0dp"
+        android:layout_marginTop="16dp"
+        android:layout_weight="1">
+
+        <androidx.swiperefreshlayout.widget.SwipeRefreshLayout
+            android:id="@+id/app_list_refresh"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent">
+
+            <androidx.recyclerview.widget.RecyclerView
+                android:id="@+id/app_list"
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                android:clipToPadding="false"
+                android:fastScrollAlwaysVisible="true"
+                android:fastScrollEnabled="true"
+                android:paddingBottom="16dp" />
+        </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>
+
+        <LinearLayout
+            android:id="@+id/app_list_loading"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:gravity="center"
+            android:orientation="vertical">
+
+            <ProgressBar
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content" />
+
+            <TextView
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="8dp"
+                android:text="Loading apps…" />
+        </LinearLayout>
+    </FrameLayout>
+</LinearLayout>