refactor: cleanups

refactor: toSentenceCase

1. Replace Activity with Context (activities are also Context)
2. Add method that accepts `Resources`
3. Remove repeated code

fix: check if HeaderFragment is attached

parentFragmentManager may throw if not

refactor: inline ViewerCommand::allDefaultBindings

Only used in tests

refactor: use Kotlin notation instead of java BiFunction

refactor: inline removeBinding

only used in a test

refactor: inline keyMap

IDE suggestion

AnkiDroid/src/main/java/com/ichi2/anki/cardviewer/ViewerCommand.kt

@@ -29,9 +29,6 @@ import com.ichi2.anki.reviewer.MappableBinding
 import com.ichi2.anki.reviewer.MappableBinding.Companion.fromPreference
 import com.ichi2.anki.reviewer.MappableBinding.Companion.toPreferenceString
 import com.ichi2.anki.reviewer.MappableBinding.Screen
-import java.util.Arrays
-import java.util.function.BiFunction
-import java.util.stream.Collectors
 
 /** Abstraction: Discuss moving many of these to 'Reviewer'  */
 enum class ViewerCommand(
@@ -91,13 +88,6 @@ enum class ViewerCommand(
     ;
 
     companion object {
-        val allDefaultBindings: List<MappableBinding>
-            get() =
-                Arrays
-                    .stream(entries.toTypedArray())
-                    .flatMap { x: ViewerCommand -> x.defaultValue.stream() }
-                    .collect(Collectors.toList())
-
         fun fromPreferenceKey(key: String) = entries.first { it.preferenceKey == key }
     }
 
@@ -108,54 +98,42 @@ enum class ViewerCommand(
         preferences: SharedPreferences,
         binding: MappableBinding,
     ) {
-        val addAtStart =
-            BiFunction { collection: MutableList<MappableBinding>, element: MappableBinding ->
-                // reorder the elements, moving the added binding to the first position
-                collection.remove(element)
-                collection.add(0, element)
-                true
-            }
+        val addAtStart: (MutableList<MappableBinding>, MappableBinding) -> Boolean = { collection, element ->
+            // reorder the elements, moving the added binding to the first position
+            collection.remove(element)
+            collection.add(0, element)
+            true
+        }
         addBindingInternal(preferences, binding, addAtStart)
     }
 
     fun addBindingAtEnd(
         preferences: SharedPreferences,
         binding: MappableBinding,
     ) {
-        val addAtEnd =
-            BiFunction { collection: MutableList<MappableBinding>, element: MappableBinding ->
-                // do not reorder the elements
-                if (collection.contains(element)) {
-                    return@BiFunction false
-                }
+        val addAtEnd: (MutableList<MappableBinding>, MappableBinding) -> Boolean = { collection, element ->
+            // do not reorder the elements
+            if (collection.contains(element)) {
+                false
+            } else {
                 collection.add(element)
-                return@BiFunction true
+                true
             }
+        }
         addBindingInternal(preferences, binding, addAtEnd)
     }
 
     private fun addBindingInternal(
         preferences: SharedPreferences,
         binding: MappableBinding,
-        performAdd: BiFunction<MutableList<MappableBinding>, MappableBinding, Boolean>,
+        performAdd: (MutableList<MappableBinding>, MappableBinding) -> Boolean,
     ) {
         val bindings: MutableList<MappableBinding> = fromPreference(preferences, this)
-        performAdd.apply(bindings, binding)
+        performAdd(bindings, binding)
         val newValue: String = bindings.toPreferenceString()
         preferences.edit { putString(preferenceKey, newValue) }
     }
 
-    fun removeBinding(
-        prefs: SharedPreferences,
-        binding: MappableBinding,
-    ) {
-        val bindings: MutableList<MappableBinding> = MappableBinding.fromPreferenceString(preferenceKey)
-        bindings.remove(binding)
-        prefs.edit {
-            putString(preferenceKey, bindings.toPreferenceString())
-        }
-    }
-
     // If we use the serialised format, then this adds additional coupling to the properties.
     val defaultValue: List<MappableBinding>
         get() {

AnkiDroid/src/main/java/com/ichi2/anki/preferences/HeaderFragment.kt

@@ -73,6 +73,7 @@ class HeaderFragment :
             }
 
             parentFragmentManager.addOnBackStackChangedListener {
+                if (!isAdded) return@addOnBackStackChangedListener
                 val fragment =
                     parentFragmentManager.findFragmentById(R.id.settings_container)
                         ?: return@addOnBackStackChangedListener

AnkiDroid/src/main/java/com/ichi2/anki/reviewer/PeripheralKeymap.kt

@@ -32,7 +32,7 @@ class PeripheralKeymap(
     reviewerUi: ReviewerUi,
     commandProcessor: ViewerCommand.CommandProcessor,
 ) {
-    private val keyMap: KeyMap
+    private val keyMap: KeyMap = KeyMap(commandProcessor, reviewerUi) { Screen.Reviewer(it) }
     private var hasSetup = false
 
     fun setup() {
@@ -110,8 +110,4 @@ class PeripheralKeymap(
 
         operator fun get(key: MappableBinding): ViewerCommand? = bindingMap[key]
     }
-
-    init {
-        keyMap = KeyMap(commandProcessor, reviewerUi) { Screen.Reviewer(it) }
-    }
 }

AnkiDroid/src/main/java/com/ichi2/anki/ui/internationalization/SentenceCase.kt

@@ -16,7 +16,7 @@
 
 package com.ichi2.anki.ui.internationalization
 
-import android.app.Activity
+import android.content.Context
 import androidx.annotation.StringRes
 import androidx.fragment.app.Fragment
 
@@ -30,10 +30,10 @@ import androidx.fragment.app.Fragment
  * ```
  */
 fun String.toSentenceCase(
-    activity: Activity,
+    context: Context,
     @StringRes resId: Int,
 ): String {
-    val resString = activity.getString(resId)
+    val resString = context.getString(resId)
     // lowercase both for the comparison: sentence case doesn't mean all words are lowercase
     if (this.lowercase() == resString.lowercase()) return resString
     return this
@@ -42,9 +42,4 @@ fun String.toSentenceCase(
 fun String.toSentenceCase(
     fragment: Fragment,
     @StringRes resId: Int,
-): String {
-    val resString = fragment.getString(resId)
-    // lowercase both for the comparison: sentence case doesn't mean all words are lowercase
-    if (this.lowercase() == resString.lowercase()) return resString
-    return this
-}
+): String = toSentenceCase(fragment.requireContext(), resId)

AnkiDroid/src/test/java/com/ichi2/anki/ReviewerNoParamTest.kt

@@ -32,6 +32,7 @@ import com.ichi2.anki.reviewer.Binding
 import com.ichi2.anki.reviewer.FullScreenMode
 import com.ichi2.anki.reviewer.FullScreenMode.Companion.setPreference
 import com.ichi2.anki.reviewer.MappableBinding
+import com.ichi2.anki.reviewer.MappableBinding.Companion.toPreferenceString
 import com.ichi2.anki.reviewer.MappableBinding.Screen
 import com.ichi2.libanki.Consts
 import com.ichi2.libanki.DeckId
@@ -299,7 +300,12 @@ class ReviewerNoParamTest : RobolectricTest() {
             for (mappableBinding in MappableBinding.fromPreference(prefs, command)) {
                 val gestureBinding = mappableBinding.binding as? Binding.GestureInput? ?: continue
                 if (gestureBinding.gesture in gestures) {
-                    command.removeBinding(prefs, mappableBinding)
+                    val bindings: MutableList<MappableBinding> =
+                        MappableBinding.fromPreferenceString(command.preferenceKey)
+                    bindings.remove(mappableBinding)
+                    prefs.edit {
+                        putString(command.preferenceKey, bindings.toPreferenceString())
+                    }
                 }
             }
         }

AnkiDroid/src/test/java/com/ichi2/anki/reviewer/MappableBindingTest.kt

@@ -17,10 +17,13 @@ package com.ichi2.anki.reviewer
 
 import android.view.KeyEvent
 import com.ichi2.anki.cardviewer.ViewerCommand
+import com.ichi2.anki.cardviewer.ViewerCommand.entries
 import org.hamcrest.MatcherAssert.assertThat
 import org.hamcrest.Matchers.hasItem
 import org.hamcrest.Matchers.not
 import org.junit.Test
+import java.util.Arrays
+import java.util.stream.Collectors
 
 class MappableBindingTest {
     @Test
@@ -39,7 +42,11 @@ class MappableBindingTest {
         assertThat(allBindings, not(hasItem(keyCode(KeyEvent.KEYCODE_L))))
     }
 
-    private fun getAllBindings() = ViewerCommand.allDefaultBindings
+    private fun getAllBindings() =
+        Arrays
+            .stream(entries.toTypedArray())
+            .flatMap { x: ViewerCommand -> x.defaultValue.stream() }
+            .collect(Collectors.toList())
 
     @Suppress("SameParameterValue")
     private fun keyCode(code: Int) = fromBinding(BindingTest.keyCode(code))