Added Event.kt class for exceptions handling and showing

app/src/main/java/com/rtbishop/look4sat/SharedViewModel.kt

@@ -24,10 +24,7 @@ import androidx.hilt.Assisted
 import androidx.hilt.lifecycle.ViewModelInject
 import androidx.lifecycle.*
 import com.github.amsacode.predict4java.GroundStationPosition
-import com.rtbishop.look4sat.data.Result
-import com.rtbishop.look4sat.data.SatEntry
-import com.rtbishop.look4sat.data.SatPass
-import com.rtbishop.look4sat.data.TleSource
+import com.rtbishop.look4sat.data.*
 import com.rtbishop.look4sat.repo.EntriesRepo
 import com.rtbishop.look4sat.repo.SourcesRepo
 import com.rtbishop.look4sat.repo.TransmittersRepo
@@ -50,6 +47,7 @@ class SharedViewModel @ViewModelInject constructor(
 
     private val _currentTimeMillis = MutableLiveData(System.currentTimeMillis())
     private val _passes = MutableLiveData<Result<MutableList<SatPass>>>()
+    private val _appEvent = MutableLiveData<Event<Any>>()
     private var selectedEntries = emptyList<SatEntry>()
     private var shouldTriggerCalculation = true
 
@@ -64,8 +62,13 @@ class SharedViewModel @ViewModelInject constructor(
     fun getEntries() = entriesRepo.getEntries()
     fun getCurrentTimeMillis(): LiveData<Long> = _currentTimeMillis
     fun getPasses(): LiveData<Result<MutableList<SatPass>>> = _passes
+    fun getAppEvent(): LiveData<Event<Any>> = _appEvent
     fun getTransmittersForSat(satId: Int) = transmittersRepo.getTransmittersForSat(satId)
 
+    fun postAppEvent(event: Event<Any>) {
+        _appEvent.value = event
+    }
+
     fun triggerCalculation() {
         if (shouldTriggerCalculation) {
             shouldTriggerCalculation = false
@@ -79,15 +82,23 @@ class SharedViewModel @ViewModelInject constructor(
 
     fun updateEntriesFromFile(uri: Uri) {
         viewModelScope.launch {
-            entriesRepo.updateEntriesFromFile(uri)
+            try {
+                entriesRepo.updateEntriesFromFile(uri)
+            } catch (exception: Exception) {
+                postAppEvent(Event(exception))
+            }
         }
     }
 
     fun updateEntriesFromSources(sources: List<TleSource>) {
         viewModelScope.launch {
-            sourcesRepo.updateSources(sources)
-            entriesRepo.updateEntriesFromSources(sources)
-            transmittersRepo.updateTransmitters()
+            try {
+                sourcesRepo.updateSources(sources)
+                entriesRepo.updateEntriesFromSources(sources)
+                transmittersRepo.updateTransmitters()
+            } catch (exception: Exception) {
+                postAppEvent(Event(exception))
+            }
         }
     }
 

app/src/main/java/com/rtbishop/look4sat/data/Event.kt

@@ -0,0 +1,17 @@
+package com.rtbishop.look4sat.data
+
+class Event<out T>(private val content: T) {
+
+    private var hasBeenHandled = false
+
+    fun getContentIfNotHandled(): T? {
+        return if (hasBeenHandled) {
+            null
+        } else {
+            hasBeenHandled = true
+            content
+        }
+    }
+
+    fun peekContent(): T = content
+}

app/src/main/java/com/rtbishop/look4sat/ui/fragments/EntriesFragment.kt

@@ -16,6 +16,7 @@ import com.rtbishop.look4sat.data.SatEntry
 import com.rtbishop.look4sat.data.TleSource
 import com.rtbishop.look4sat.databinding.FragmentEntriesBinding
 import com.rtbishop.look4sat.ui.adapters.EntriesAdapter
+import com.rtbishop.look4sat.utility.Utilities.snack
 import dagger.hilt.android.AndroidEntryPoint
 
 @AndroidEntryPoint
@@ -62,6 +63,11 @@ class EntriesFragment : Fragment(R.layout.fragment_entries) {
             viewModel.setSelectedEntries(it)
             entriesAdapter.setEntries(it as MutableList<SatEntry>)
         })
+        viewModel.getAppEvent().observe(viewLifecycleOwner, { event ->
+            event.getContentIfNotHandled()?.let {
+                getString(R.string.error_updating_data).snack(requireView())
+            }
+        })
     }
 
     private fun showImportFromWebDialog() {

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

@@ -51,8 +51,7 @@
     <string name="no_downlink_doppler">Тек. нисход: нет</string>
     <string name="no_trans">Не найдены трансиверы для этого спутника</string>
 
-    <string name="err_update_data">Пожалуйста, обновите данные спутников</string>
-    <string name="err_enter_value">Пожалуйста, введите значение</string>
+    <string name="error_updating_data">Ошибка импорта спутников</string>
 
     <string name="pass_aos_az">НПС — %2d°</string>
     <string name="pass_los_az">%2d° — КПС</string>

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

@@ -52,8 +52,7 @@
     <string name="no_downlink_doppler">Curr. downlink: null</string>
     <string name="no_trans">No transceivers found for this satellite</string>
 
-    <string name="err_update_data">Please, update satellite data</string>
-    <string name="err_enter_value">Please, enter the value</string>
+    <string name="error_updating_data">Error importing satellite data</string>
 
     <string name="pass_satName" translatable="false">%s</string>
     <string name="pass_satId" translatable="false">ID: %d</string>