Added catches for some errors, Allowed to write schedule to any calendar

GUT.Schedule/GUT.Schedule/Activities/ExportActivity.cs

@@ -1,7 +1,9 @@
 using Android.App;
+using Android.Content;
 using Android.OS;
 using Android.Widget;
 using GUT.Schedule.Models;
+using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
 
@@ -22,17 +24,30 @@ namespace GUT.Schedule
 
             status = FindViewById<TextView>(Resource.Id.status);
 
-            status.Text = "Загрузка расписания";
-            List<Subject> schedule = await Parser.LoadSchedule();
+            try
+            {
+                status.Text = "Загрузка расписания";
+                List<Subject> schedule = await Parser.LoadSchedule();
 
-            schedule = schedule.FindAll(i => i.StartTime.Date >= Data.StartDate && i.StartTime.Date <= Data.EndDate);   // Filtering schedule according to export range
+                schedule = schedule.FindAll(i => i.StartTime.Date >= Data.StartDate && i.StartTime.Date <= Data.EndDate);   // Filtering schedule according to export range
 
-            status.Text = "Экспортирование в календарь";
-            Calendar.Export(schedule);
+                status.Text = "Экспортирование в календарь";
+                Calendar.Export(schedule);
 
 
-            status.Text = "Готово";
-            await Task.Delay(1000);
+                status.Text = "Готово";
+                await Task.Delay(1000);
+            }
+            catch (Exception e)
+            {
+                Android.Support.V7.App.AlertDialog.Builder builder = new Android.Support.V7.App.AlertDialog.Builder(this);
+                builder.SetMessage(e.Message)
+                    .SetTitle(e.GetType().ToString())
+                    .SetPositiveButton("ОК", (EventHandler<DialogClickEventArgs>)null);
+
+                Android.Support.V7.App.AlertDialog dialog = builder.Create();
+                dialog.Show();
+            }
             base.OnBackPressed();   // Navigates back to main activity (always because I don't allow backward navigation)
         }
 

GUT.Schedule/GUT.Schedule/Activities/StartActivity.cs

@@ -8,6 +8,7 @@ using Android.Support.V4.App;
 using Android.Support.V4.Content;
 using Android.Support.V7.App;
 using Android.Widget;
+using System;
 using System.Linq;
 using System.Net.Http;
 
@@ -33,7 +34,7 @@ namespace GUT.Schedule
             if (ContextCompat.CheckSelfPermission(this, Manifest.Permission.WriteCalendar) != Permission.Granted)
             {
                 if (ActivityCompat.ShouldShowRequestPermissionRationale(this, Manifest.Permission.WriteCalendar))
-                    ShowDialog();
+                    ShowRationale();
                 else
                     RequestPermissions();
             }
@@ -43,15 +44,31 @@ namespace GUT.Schedule
 
         private async void Proceed()
         {
-            status.Text = "Загрузка списка календарей";
-            Calendar.LoadCalendars();
+            try
+            {
+                status.Text = "Загрузка списка календарей";
+                Calendar.LoadCalendars();
+                if (Calendar.Calendars.Count == 0)
+                    ShowDialog("Создайте новый календарь", "На вашем устройстве нет календарей пригодных для записи расписания");
+            }
+            catch (Exception e)
+            {
+                ShowDialog(e.GetType().ToString(), e.Message);
+            }
 
-            status.Text = "Загрузка списка факультетов";
-            await Parser.LoadFaculties();
+            try
+            {
+                status.Text = "Загрузка списка факультетов";
+                await Parser.LoadFaculties();
 
-            status.Text = "Загрузка дат смещения";
-            using (HttpClient client = new HttpClient())
+                status.Text = "Загрузка дат смещения";
+                using HttpClient client = new HttpClient();
                 Data.FirstWeekDay = int.Parse(await client.GetStringAsync("https://xfox111.net/schedule_offset.txt"));
+            }
+            catch
+            {
+                ShowDialog("Не удалось загрузить данные", "Проверьте интернет-соединение или попробуйте позже");
+            }
 
             StartActivity(new Intent(this, typeof(MainActivity)));
         }
@@ -63,7 +80,7 @@ namespace GUT.Schedule
             if (grantResults.All(i => i == Permission.Granted))
                 Proceed();
             else
-                ShowDialog();
+                ShowRationale();
         }
 
         private void RequestPermissions() =>
@@ -74,7 +91,7 @@ namespace GUT.Schedule
                 Manifest.Permission.Internet
             }, 76);     // IDK why I need requestCode value to be set (instead of 76 there can be any other number. Anyway it doesn't affect anything)
 
-        private void ShowDialog()
+        private void ShowRationale()
         {
             Android.Support.V7.App.AlertDialog.Builder builder = new Android.Support.V7.App.AlertDialog.Builder(this);
             builder.SetMessage("Разрешите приложению получать доступ к календарю. Без этого разрешения приложение не сможет добавлять расписание в ваш календарь")
@@ -85,6 +102,17 @@ namespace GUT.Schedule
             dialog.Show();
         }
 
+        private void ShowDialog(string title, string content)
+        {
+            Android.Support.V7.App.AlertDialog.Builder builder = new Android.Support.V7.App.AlertDialog.Builder(this);
+            builder.SetMessage(content)
+                .SetTitle(title)
+                .SetPositiveButton("ОК", (EventHandler<DialogClickEventArgs>)null);
+
+            Android.Support.V7.App.AlertDialog dialog = builder.Create();
+            dialog.Show();
+        }
+
         public override void OnBackPressed() { }    // Disables back button
     }
 }

GUT.Schedule/GUT.Schedule/Calendar.cs

@@ -27,9 +27,7 @@ namespace GUT.Schedule
             string[] calendarsProjection = {
                 CalendarContract.Calendars.InterfaceConsts.Id,
                 CalendarContract.Calendars.InterfaceConsts.CalendarDisplayName,
-                CalendarContract.Calendars.InterfaceConsts.AccountName,
-                CalendarContract.Calendars.InterfaceConsts.OwnerAccount,
-                CalendarContract.Calendars.InterfaceConsts.AccountType,
+                CalendarContract.Calendars.InterfaceConsts.AccountName
             };
 
             // Retrieving calendars data
@@ -38,8 +36,7 @@ namespace GUT.Schedule
             cursor.MoveToNext();
             for (int i = 0; i < cursor.Count; i++)
             {
-                if (cursor.GetString(4) == "com.google" && !cursor.GetString(3).Contains("google"))         // Loading only users' main calendars
-                    Calendars.Add((cursor.GetString(0), $"{cursor.GetString(1)} ({cursor.GetString(2)})"));
+                Calendars.Add((cursor.GetString(0), $"{cursor.GetString(1)} ({cursor.GetString(2)})"));
                 cursor.MoveToNext();
             }
         }

GUT.Schedule/GUT.Schedule/Properties/AndroidManifest.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="101" android:versionName="1.0.1" package="com.xfox111.gut.schedule" android:installLocation="auto">
+<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="102" android:versionName="1.0.2" package="com.xfox111.gut.schedule" android:installLocation="auto">
 	<uses-sdk android:minSdkVersion="16" android:targetSdkVersion="28" />
 	<application android:allowBackup="true" android:icon="@mipmap/ic_launcher" android:label="ГУТ.Расписание" android:roundIcon="@mipmap/ic_launcher_round" android:supportsRtl="true" android:theme="@style/AppTheme.NoActionBar"></application>
 	<uses-permission android:name="android.permission.READ_CALENDAR" />