CanteenFragment.kt: replaced buttons for opening hours and canteen switch embedded in the app bar with floating action buttons; implemented a possible fix for the app crashing after refreshing the canteen plan. This may have been caused by accessing the view/context of the fragment to let the user know that the refresh succeeded or encountered an error. Reference will be null by the time the fragment is inactive, causing a NullPointerException

app/src/main/java/com/denizk0461/studip/adapter/StudIPEventItemAdapter.kt

@@ -35,7 +35,6 @@ class StudIPEventItemAdapter(
 
     /**
      * Retrieve an instance of Calendar to check whether the adapter's day matches the current day.
-     * TODO this can be optimised by checking in EventPageFragment.kt and delivering a boolean
      */
     private val currentCalendar = Calendar.getInstance()
 

app/src/main/java/com/denizk0461/studip/data/StwParser.kt

@@ -128,10 +128,7 @@ class StwParser(application: Application) {
         // Parse the HTML using Jsoup to traverse the document
         val doc = Jsoup.connect(url).get()
 
-        /*
-         * Retrieve the opening hours for the canteen.
-         * TODO this formatting sucks and also this doesn't work
-         */
+        // Retrieve the opening hours for the canteen
         var openingHours = ""
 
         // Iterate through all wrappers that could contain opening hours
@@ -139,10 +136,7 @@ class StwParser(application: Application) {
             // Element is not for providing contact details
             if (it.getElementsByClass("contact-person-name").size == 0) {
 
-                /*
-                 * Retrieve all opening hours.
-                 * TODO this slows down the fetch SIGNIFICANTLY, but why?
-                 */
+                // Retrieve all opening hours.
                 it.children().forEach { element ->
                     if (element.tag().toString() == "p") {
                         openingHours += element.textWithBreaks().trim() + "\n" // Uni-Mensa is not parsed properly

app/src/main/java/com/denizk0461/studip/fragment/CanteenFragment.kt

@@ -53,53 +53,18 @@ class CanteenFragment : AppFragment() {
         // Set progress circle colours
         binding.swipeRefreshLayout.setRainbowProgressCircle()
 
-        // Open the menu for the canteen picker button
-        binding.buttonCanteenPicker.setOnClickListener {
-            PopupMenu(binding.root.context, binding.buttonCanteenPicker).apply {
-                setOnMenuItemClickListener { item ->
-                    viewModel.preferenceCanteen = when (item?.itemId) {
-                        R.id.mensa_uni -> 0
-                        R.id.cafe_central -> 1
-                        R.id.mensa_nw1 -> 2
-                        R.id.cafeteria_gw2 -> 3
-                        R.id.mensa_neustadt -> 4
-                        R.id.mensa_werder -> 5
-                        R.id.mensa_airport -> 6
-                        R.id.mensa_bhv -> 7
-                        R.id.cafeteria_bhv -> 8
-                        R.id.mensa_hfk -> 9
-                        else -> 0
-                    }
-                    // Set newly selected canteen to the button
-                    binding.buttonCanteenPicker.text = getCurrentlySelectedCanteenName()
-
-                    // Display to the user that the canteen plan will be refreshed
-                    binding.swipeRefreshLayout.isRefreshing = true
-
-                    // Refresh the canteen menu for the newly selected canteen
-                    refresh()
-                    true
-                }
-                inflate(R.menu.menu_canteens)
-                show()
-            }
-        }
-
         // Set currently selected canteen to the button
-        binding.buttonCanteenPicker.text = getCurrentlySelectedCanteenName()
+//        binding.buttonCanteenPicker.text = getCurrentlySelectedCanteenName()
+        binding.appTitleBar.text = getString(
+            R.string.title_canteen_template,
+            getCurrentlySelectedCanteenName(),
+        )
+        binding.appTitleBar.isSelected = true
 
         // Set up button to display info (most likely opening hours)
-        binding.buttonInfo.setOnClickListener {
-            openBottomSheet(
-                getTextSheet(
-                    getString(
-                        R.string.canteen_opening_hours,
-                        getCurrentlySelectedCanteenName()
-                    ),
-                    openingHours
-                )
-            )
-        }
+//        binding.buttonInfo.setOnClickListener {
+//
+//        }
 
         // Assign a preference value to every button to filter for dietary preferences
         val chipMap = mapOf(
@@ -127,6 +92,55 @@ class CanteenFragment : AppFragment() {
             }
         }
 
+        // Set up floating action button for viewing the opening hours
+        binding.fabOpeningHours.setOnClickListener {
+            openBottomSheet(
+                getTextSheet(
+                    getString(
+                        R.string.canteen_opening_hours,
+                        getCurrentlySelectedCanteenName()
+                    ),
+                    openingHours
+                )
+            )
+        }
+
+        // Set up floating action button for switching the canteen
+        binding.fabSwitchCanteen.setOnClickListener {
+            PopupMenu(binding.root.context, binding.fabSwitchCanteen).apply {
+                setOnMenuItemClickListener { item ->
+                    viewModel.preferenceCanteen = when (item?.itemId) {
+                        R.id.mensa_uni -> 0
+                        R.id.cafe_central -> 1
+                        R.id.mensa_nw1 -> 2
+                        R.id.cafeteria_gw2 -> 3
+                        R.id.mensa_neustadt -> 4
+                        R.id.mensa_werder -> 5
+                        R.id.mensa_airport -> 6
+                        R.id.mensa_bhv -> 7
+                        R.id.cafeteria_bhv -> 8
+                        R.id.mensa_hfk -> 9
+                        else -> 0
+                    }
+                    // Set newly selected canteen to the button
+//                    binding.buttonCanteenPicker.text = getCurrentlySelectedCanteenName()
+                    binding.appTitleBar.text = getString(
+                        R.string.title_canteen_template,
+                        getCurrentlySelectedCanteenName(),
+                    )
+
+                    // Display to the user that the canteen plan will be refreshed
+                    binding.swipeRefreshLayout.isRefreshing = true
+
+                    // Refresh the canteen menu for the newly selected canteen
+                    refresh()
+                    true
+                }
+                inflate(R.menu.menu_canteens)
+                show()
+            }
+        }
+
         // Set up floating action button for refreshing the canteen offers
         binding.fabRefreshOffers.setOnClickListener {
             // Display to the user that a refresh is in progress
@@ -224,21 +238,27 @@ class CanteenFragment : AppFragment() {
     private fun refresh() {
         // Retrieve new offers from the website(s)
         viewModel.fetchOffers(viewModel.preferenceCanteen, onFinish = {
-            /*
-             * Tell the swipe refresh layout to stop refreshing.
-             */
-            binding.swipeRefreshLayout.isRefreshing = false
+            // Check if the fragment is still active
+            if (_binding != null) {
+                /*
+                 * Tell the swipe refresh layout to stop refreshing.
+                 */
+                binding.swipeRefreshLayout.isRefreshing = false
+            }
 
         }, onError = {
-            // Tell the user that an error occurred
-            context.theme?.showErrorSnackBar(
-                binding.snackbarContainer,
-                getString(R.string.canteen_fetch_error)
-            )
-            /*
+            // Check if the fragment is still active
+            if (_binding != null) {
+                // Tell the user that an error occurred
+                context.theme?.showErrorSnackBar(
+                    binding.snackbarContainer,
+                    getString(R.string.canteen_fetch_error)
+                )
+                /*
              * Tell the swipe refresh layout to stop refreshing.
              */
-            binding.swipeRefreshLayout.isRefreshing = false
+                binding.swipeRefreshLayout.isRefreshing = false
+            }
         })
     }
 }

app/src/main/java/com/denizk0461/studip/model/AllergenPreferences.kt

@@ -1,6 +1,10 @@
 package com.denizk0461.studip.model
 
-// TODO KDoc
+/**
+ * Class for managing allergen preferences. The user can tell the app which substances they are
+ * allergic against, and the functions in this class can be used to filter out offers containing
+ * allergens that could kill them.
+ */
 class AllergenPreferences {
 
     /**
@@ -69,8 +73,13 @@ class AllergenPreferences {
          * @return      string with preferences inserted
          */
         fun deconstruct(): String {
+            // Create an empty list
             val array = arrayListOf<String>()
 
+            /*
+             * Add the symbols for the allergens to the list. Allergen symbols derived from the
+             * allergen list at stw-bremen.de
+             */
             if (hasWheat) array.add("a1")
             if (hasRye) array.add("a2")
             if (hasBarley) array.add("a3")
@@ -98,6 +107,7 @@ class AllergenPreferences {
             if (hasSesame) array.add("m")
             if (hasMolluscs) array.add("n")
 
+            // Join the individual symbols to a single string
             return array.joinToString(",")
         }
     }
@@ -116,6 +126,7 @@ class AllergenPreferences {
          * @return      instance of AllergenPreferences.Object with preferences inserted
          */
         fun construct(input: String): Object {
+            // Split the string into its individual components
             val elements = input.split(",")
             return Object(
                 elements.contains("a1"),

app/src/main/res/drawable/arrow_down.xml

@@ -0,0 +1,5 @@
+<vector android:height="24dp" android:tint="#000000"
+    android:viewportHeight="24" android:viewportWidth="24"
+    android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="@android:color/white" android:pathData="M7.41,8.59L12,13.17l4.59,-4.58L18,10l-6,6 -6,-6 1.41,-1.41z"/>
+</vector>

app/src/main/res/drawable/clock.xml

@@ -0,0 +1,6 @@
+<vector android:height="24dp" android:tint="#000000"
+    android:viewportHeight="24" android:viewportWidth="24"
+    android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="@android:color/white" android:pathData="M11.99,2C6.47,2 2,6.48 2,12s4.47,10 9.99,10C17.52,22 22,17.52 22,12S17.52,2 11.99,2zM12,20c-4.42,0 -8,-3.58 -8,-8s3.58,-8 8,-8 8,3.58 8,8 -3.58,8 -8,8z"/>
+    <path android:fillColor="@android:color/white" android:pathData="M12.5,7H11v6l5.25,3.15 0.75,-1.23 -4.5,-2.67z"/>
+</vector>

app/src/main/res/drawable/switch_arrows.xml

@@ -0,0 +1,6 @@
+<vector android:height="24dp" android:tint="#000000"
+    android:viewportHeight="24" android:viewportWidth="24"
+    android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="@android:color/white" android:pathData="M18,12l4,-4l-4,-4l0,3l-15,0l0,2l15,0z"/>
+    <path android:fillColor="@android:color/white" android:pathData="M6,12l-4,4l4,4l0,-3l15,0l0,-2l-15,0z"/>
+</vector>

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

@@ -1,6 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
     android:id="@+id/snackbar_container"
     android:layout_width="match_parent"
     android:layout_height="match_parent">
@@ -17,48 +18,21 @@
             android:orientation="vertical"
             app:layout_scrollFlags="scroll|exitUntilCollapsed">
 
-            <com.google.android.material.button.MaterialButton
-                android:id="@+id/button_canteen_picker"
-                style="@style/Widget.Material3.Button.TextButton"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:textSize="18sp"
-                android:layout_gravity="start"
-                android:layout_marginStart="8dp"
-                android:fontFamily="@font/lato_bolditalic"/>
-
-            <androidx.constraintlayout.widget.ConstraintLayout
+            <TextView
+                android:id="@+id/app_title_bar"
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
-                android:layout_marginHorizontal="16dp">
-
-                <TextView
-                    android:id="@+id/app_title_bar"
-                    android:layout_width="0dp"
-                    android:layout_height="wrap_content"
-                    android:text="@string/title_food"
-                    android:textSize="32sp"
-                    android:fontFamily="@font/lato_bolditalic"
-                    app:layout_constraintTop_toTopOf="parent"
-                    app:layout_constraintBottom_toBottomOf="parent"
-                    app:layout_constraintStart_toStartOf="parent"
-                    app:layout_constraintEnd_toStartOf="@id/button_info"/>
-
-                <com.google.android.material.button.MaterialButton
-                    style="@style/Widget.Material3.Button.TextButton"
-                    android:id="@+id/button_info"
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:minWidth="0dp"
-                    app:icon="@drawable/info"
-                    app:iconPadding="0dp"
-                    android:layout_gravity="center_vertical|end"
-                    app:iconTint="?attr/colorOnSurfaceVariant"
-                    app:layout_constraintTop_toTopOf="parent"
-                    app:layout_constraintBottom_toBottomOf="parent"
-                    app:layout_constraintEnd_toEndOf="parent"/>
-
-            </androidx.constraintlayout.widget.ConstraintLayout>
+                android:text="@string/title_food"
+                android:textSize="28sp"
+                android:fontFamily="@font/lato_bolditalic"
+                android:layout_marginTop="16dp"
+                android:layout_marginHorizontal="16dp"
+                android:singleLine="true"
+                android:ellipsize="marquee"
+                android:marqueeRepeatLimit="marquee_forever"
+                android:focusable="true"
+                android:focusableInTouchMode="true"
+                android:scrollHorizontally="true"/>
 
             <HorizontalScrollView
                 android:id="@+id/scroll_view_chip"
@@ -222,16 +196,48 @@
 
     </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>
 
-    <com.google.android.material.floatingactionbutton.FloatingActionButton
-        android:id="@+id/fab_refresh_offers"
+    <androidx.appcompat.widget.LinearLayoutCompat
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        app:srcCompat="@drawable/refresh"
-        android:contentDescription="@string/canteen_fab_refresh_content_desc"
+        android:orientation="vertical"
         android:layout_gravity="bottom|end"
         android:layout_marginEnd="@dimen/fab_margin"
         android:layout_marginBottom="@dimen/fab_margin"
-        app:layout_behavior="com.google.android.material.behavior.HideBottomViewOnScrollBehavior"/>
+        app:layout_behavior="com.google.android.material.behavior.HideBottomViewOnScrollBehavior">
+
+        <com.google.android.material.floatingactionbutton.FloatingActionButton
+            style="?attr/floatingActionButtonSmallStyle"
+            android:id="@+id/fab_opening_hours"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            app:srcCompat="@drawable/clock"
+            android:contentDescription="@string/canteen_fab_opening_hours_content_desc"
+            android:layout_gravity="center_horizontal"
+            android:tooltipText="@string/canteen_fab_opening_hours_content_desc"
+            tools:ignore="UnusedAttribute"/>
+
+        <com.google.android.material.floatingactionbutton.FloatingActionButton
+            style="?attr/floatingActionButtonSmallStyle"
+            android:id="@+id/fab_switch_canteen"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            app:srcCompat="@drawable/switch_arrows"
+            android:contentDescription="@string/canteen_fab_switch_canteen_content_desc"
+            android:layout_marginBottom="8dp"
+            android:layout_gravity="center_horizontal"
+            android:tooltipText="@string/canteen_fab_switch_canteen_content_desc"
+            tools:ignore="UnusedAttribute"/>
+
+        <com.google.android.material.floatingactionbutton.FloatingActionButton
+            android:id="@+id/fab_refresh_offers"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            app:srcCompat="@drawable/refresh"
+            android:contentDescription="@string/canteen_fab_refresh_content_desc"
+            android:tooltipText="@string/canteen_fab_refresh_content_desc"
+            tools:ignore="UnusedAttribute"/>
+
+    </androidx.appcompat.widget.LinearLayoutCompat>
 
 <!--    <androidx.coordinatorlayout.widget.CoordinatorLayout-->
 <!--        android:id="@+id/snackbar_container"-->

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

@@ -17,7 +17,7 @@
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:text="@string/title_schedule"
-            android:textSize="32sp"
+            android:textSize="28sp"
             android:fontFamily="@font/lato_bolditalic"
             android:layout_marginTop="16dp"
             android:layout_marginHorizontal="16dp"

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

@@ -22,7 +22,7 @@
             android:fontFamily="@font/lato_bolditalic"
             android:text="@string/title_settings"
             app:layout_scrollFlags="scroll|exitUntilCollapsed"
-            android:textSize="32sp"/>
+            android:textSize="28sp"/>
 
     </com.google.android.material.appbar.AppBarLayout>
 

app/src/main/res/values-de/strings.xml

@@ -58,12 +58,15 @@
 
     <string name="canteen_no_offer_header">Kein Angebot</string>
     <string name="canteen_no_offer_desc">Für diesen Tag sind keine Angebote vorhanden</string>
+    <string name="canteen_fab_opening_hours_content_desc">Zeige Öffnungszeiten</string>
+    <string name="canteen_fab_switch_canteen_content_desc">Wechsle Mensa</string>
     <string name="canteen_fab_refresh_content_desc">Aktualisiere Angebote</string>
 
     <string name="sheet_licences_header">Lizenzen</string>
 
     <string name="title_schedule">Dein Stundenplan</string>
     <string name="title_food">Mensenangebote</string>
+    <string name="title_canteen_template">%s – Angebote</string>
     <string name="title_settings">App-Einstellungen</string>
 
     <string name="canteen_opening_hours">%s – Öffnungszeiten</string>

app/src/main/res/values-night/themes.xml

@@ -80,24 +80,9 @@
         <item name="colorOnPrimaryGame">@color/game_dark_onPrimary</item>
         <item name="colorContainerGame">@color/game_dark_container</item>
         <item name="colorOnContainerGame">@color/game_dark_onContainer</item>
-
-        <item name="materialTimePickerTheme">@style/TimeDialogTheme</item>
     </style>
 
     <style name="DividerTheme" parent="Widget.Material3.MaterialDivider">
         <item name="dividerColor">@color/md_theme_dark_outlineVariant</item>
     </style>
-
-    <style name="TimeDialogTheme" parent="ThemeOverlay.MaterialComponents.Dialog">
-        <item name="android:colorAccent">@color/md_theme_dark_primary</item>
-        <item name="android:colorPrimary">@color/md_theme_dark_primary</item>
-        <item name="android:colorPrimaryDark">@color/md_theme_dark_secondary</item>
-<!--        <item name="buttonBarPositiveButtonStyle">@style/TextButton</item>-->
-<!--        <item name="buttonBarNegativeButtonStyle">@style/TextButton</item>-->
-    </style>
-
-    <style name="TextButton" parent="Widget.MaterialComponents.Button.TextButton.Dialog">
-        <item name="android:textColor">@color/md_theme_dark_primary</item>
-        <item name="backgroundTint">@color/md_theme_dark_primary</item>
-    </style>
 </resources>

app/src/main/res/values/strings.xml

@@ -59,6 +59,8 @@
 
     <string name="canteen_no_offer_header">No offers</string>
     <string name="canteen_no_offer_desc">There are no offers available for this day</string>
+    <string name="canteen_fab_opening_hours_content_desc">Show opening hours</string>
+    <string name="canteen_fab_switch_canteen_content_desc">Switch canteen</string>
     <string name="canteen_fab_refresh_content_desc">Refresh offers</string>
 
     <string name="sheet_licences_header">Licences</string>
@@ -66,6 +68,7 @@
 
     <string name="title_schedule">Your Schedule</string>
     <string name="title_food">Canteen Offers</string>
+    <string name="title_canteen_template">%s – Offers</string>
     <string name="title_settings">App Settings</string>
 
     <string name="canteen_opening_hours">%s – Opening Hours</string>

app/src/main/res/values/themes.xml

@@ -80,8 +80,6 @@
         <item name="colorOnPrimaryGame">@color/game_light_onPrimary</item>
         <item name="colorContainerGame">@color/game_light_container</item>
         <item name="colorOnContainerGame">@color/game_light_onContainer</item>
-
-        <item name="materialTimePickerTheme">@style/TimeDialogTheme</item> <!-- TimePicker dialog -->
     </style>
 
     <style name="Theme.StudIPTimetable" parent="Base.Theme.StudIPTimetable" />
@@ -94,17 +92,4 @@
         <item name="checkedIconEnabled">false</item>
         <item name="checkedIcon">@null</item>
     </style>
-
-    <style name="TimeDialogTheme" parent="ThemeOverlay.MaterialComponents.TimePicker">
-        <item name="android:colorAccent">@color/md_theme_light_primary</item>
-        <item name="android:colorPrimary">@color/md_theme_light_primary</item>
-        <item name="android:colorPrimaryDark">@color/md_theme_light_secondary</item>
-        <item name="buttonBarPositiveButtonStyle">@style/TextButton</item>
-        <item name="buttonBarNegativeButtonStyle">@style/TextButton</item>
-    </style>
-
-    <style name="TextButton" parent="Widget.MaterialComponents.Button.TextButton.Dialog">
-        <item name="android:textColor">@color/md_theme_light_primary</item>
-        <item name="backgroundTint">@color/md_theme_light_primary</item>
-    </style>
 </resources>