Modified logic to more consistently show the fetch button if the schedule is empty, and hide it if there are schedule items

app/src/main/java/com/denizk0461/weserplaner/data/StudIPParser.kt

@@ -2,7 +2,6 @@ package com.denizk0461.weserplaner.data
 
 import android.app.Application
 import com.denizk0461.weserplaner.db.AppRepository
-import com.denizk0461.weserplaner.model.SettingsPreferences
 import com.denizk0461.weserplaner.model.StudIPEvent
 import org.jsoup.Jsoup
 import org.jsoup.nodes.Document
@@ -110,9 +109,6 @@ class StudIPParser(application: Application) {
         // After fetching has finished, save the list of new items into persistent storage
         repo.insertEvents(newEvents)
 
-        // Set that the user has modified their schedule
-        repo.setPreference(SettingsPreferences.HAS_MODIFIED_SCHEDULE, true)
-
         // Return the count of elements that were not able to be fetched
         return elementsNotFetched
     }

app/src/main/java/com/denizk0461/weserplaner/db/AppDAO.kt

@@ -14,12 +14,12 @@ interface AppDAO {
     /* --- Stud.IP schedule events --- */
 
     /**
-     * Retrieves all Stud.IP events, ordered by their timeslots, then their IDs.
+     * Retrieves the number of Stud.IP events available in the database.
      *
-     * @return all Stud.IP events exposed through a LiveData object
+     * @return number of Stud.IP events
      */
-    @get:Query("SELECT * FROM studip_events ORDER BY timeslotId, eventId")
-    val allEvents: LiveData<List<StudIPEvent>>
+    @Query("SELECT COUNT(*) FROM studip_events ORDER BY timeslotId, eventId")
+    fun getEventCount(): LiveData<Int>
 
     /**
      * Retrieves Stud.IP events for a specific day, ordered by their timeslots, then their IDs.

app/src/main/java/com/denizk0461/weserplaner/db/AppRepository.kt

@@ -52,6 +52,13 @@ class AppRepository(app: Application) {
         }
     }
 
+    /**
+     * Retrieves the number of Stud.IP events available in the database.
+     *
+     * @return number of Stud.IP events
+     */
+    fun getEventCount(): LiveData<Int> = dao.getEventCount()
+
     /**
      * Retrieves Stud.IP events for a specific day, ordered by their timeslots, then their IDs.
      *

app/src/main/java/com/denizk0461/weserplaner/fragment/EventFragment.kt

@@ -5,7 +5,6 @@ import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
-import androidx.fragment.app.setFragmentResultListener
 import androidx.fragment.app.viewModels
 import com.denizk0461.weserplaner.R
 import com.denizk0461.weserplaner.activity.FetcherActivity
@@ -87,12 +86,13 @@ class EventFragment : AppFragment() {
             startActivity(Intent(context, FetcherActivity::class.java))
         }
 
-        /*
-         * Set the fetch button to be visible if the user has not previously modified their schedule
-         * in any way (added an event manually or used the Stud.IP fetcher).
-         */
-        if (!viewModel.preferenceHasModifiedSchedule) {
-            binding.buttonFetchSchedule.visibility = View.VISIBLE
+        // Set visibility of the fetch button depending on whether any events have been stored
+        viewModel.getEventCount().observe(viewLifecycleOwner) { eventCount ->
+            binding.buttonFetchSchedule.visibility = if (eventCount == 0) {
+                View.VISIBLE
+            } else {
+                View.GONE
+            }
         }
 
         // Set up button for adding a new event
@@ -106,26 +106,12 @@ class EventFragment : AppFragment() {
                     val bundle = Bundle()
                     bundle.putBoolean("isEditing", false)
                     sheet.arguments = bundle
-
-                    /*
-                     * Receive fragment result to update the button visibility.
-                     * TODO doesn't work after configuration change (change into or out of multi
-                     *  window)
-                     */
-                    setFragmentResultListener("eventAdded") { _, _ ->
-                        // Hide the fetch button
-                        binding.buttonFetchSchedule.visibility = View.GONE
-                    }
                 }
             )
         }
 
         // Show the user a little message if they're opening the app for the first time
         if (viewModel.preferenceFirstLaunch) {
-
-            // Show toast
-//            showToast(context, getString(R.string.toast_first_launch))
-
             // Remember that the app has been launched before
             viewModel.preferenceFirstLaunch = false
         }

app/src/main/java/com/denizk0461/weserplaner/model/SettingsPreferences.kt

@@ -63,10 +63,5 @@ enum class SettingsPreferences(val key: String) {
      * Whether the user has opened the canteen fragment before.
      */
     HAS_OPENED_CANTEEN("has_opened_canteen"),
-
-    /**
-     * Whether the user has done something to modify their schedule.
-     */
-    HAS_MODIFIED_SCHEDULE("has_modified_schedule"),
     ;
 }

app/src/main/java/com/denizk0461/weserplaner/sheet/ScheduleUpdateSheet.kt

@@ -5,7 +5,6 @@ import android.view.View
 import android.view.ViewGroup
 import androidx.appcompat.widget.PopupMenu
 import androidx.core.widget.addTextChangedListener
-import androidx.fragment.app.setFragmentResult
 import androidx.fragment.app.viewModels
 import androidx.transition.TransitionManager
 import com.denizk0461.weserplaner.R
@@ -189,12 +188,6 @@ class ScheduleUpdateSheet : AppSheet(R.layout.sheet_schedule_update) {
                             )
                         )
 
-                        /*
-                         * Send an empty bundle to tell the parent fragment that it should update its view
-                         * according to the changes made here.
-                         */
-                        parentFragment?.setFragmentResult("eventAdded", Bundle())
-
                         // Dismiss the sheet upon update
                         dismiss()
                     }

app/src/main/java/com/denizk0461/weserplaner/viewmodel/EventViewModel.kt

@@ -1,6 +1,7 @@
 package com.denizk0461.weserplaner.viewmodel
 
 import android.app.Application
+import androidx.lifecycle.LiveData
 import com.denizk0461.weserplaner.model.SettingsPreferences
 
 /**
@@ -10,6 +11,13 @@ import com.denizk0461.weserplaner.model.SettingsPreferences
  */
 class EventViewModel(app: Application) : AppViewModel(app) {
 
+    /**
+     * Retrieves the number of Stud.IP events available in the database.
+     *
+     * @return number of Stud.IP events
+     */
+    fun getEventCount(): LiveData<Int> = repo.getEventCount()
+
     /**
      * This value determines whether the user wants their timetable to launch with the current day.
      */
@@ -28,10 +36,4 @@ class EventViewModel(app: Application) : AppViewModel(app) {
             defaultValue = true,
         )
         set(value) { repo.setPreference(SettingsPreferences.FIRST_LAUNCH, value) }
-
-    /**
-     * Determines whether the user has done something to modify their schedule.
-     */
-    val preferenceHasModifiedSchedule: Boolean
-        get() = repo.getBooleanPreference(SettingsPreferences.HAS_MODIFIED_SCHEDULE)
 }

app/src/main/java/com/denizk0461/weserplaner/viewmodel/ScheduleUpdateViewModel.kt

@@ -1,7 +1,6 @@
 package com.denizk0461.weserplaner.viewmodel
 
 import android.app.Application
-import com.denizk0461.weserplaner.model.SettingsPreferences
 import com.denizk0461.weserplaner.model.StudIPEvent
 
 class ScheduleUpdateViewModel(application: Application) : AppViewModel(application) {
@@ -11,13 +10,7 @@ class ScheduleUpdateViewModel(application: Application) : AppViewModel(applicati
      *
      * @param event the event to save
      */
-    fun insert(event: StudIPEvent) {
-        // Inser the event
-        doAsync { repo.insert(event) }
-
-        // Set that the user has modified their schedule
-        repo.setPreference(SettingsPreferences.HAS_MODIFIED_SCHEDULE, true)
-    }
+    fun insert(event: StudIPEvent) { doAsync { repo.insert(event) } }
 
     /**
      * Updates a schedule element.