Remove notification when habit is deleted

app/src/main/java/org/isoron/uhabits/commands/DeleteHabitsCommand.java

@@ -47,15 +47,14 @@ public class DeleteHabitsCommand extends Command
     }
 
     @Override
-    public void undo()
+    public Integer getExecuteStringId()
     {
-        throw new UnsupportedOperationException();
+        return R.string.toast_habit_deleted;
     }
 
-    @Override
+    public List<Habit> getHabits()
-    public Integer getExecuteStringId()
     {
-        return R.string.toast_habit_deleted;
+        return new LinkedList<>(habits);
     }
 
     @Override
@@ -63,4 +62,10 @@ public class DeleteHabitsCommand extends Command
     {
         return R.string.toast_habit_restored;
     }
+
+    @Override
+    public void undo()
+    {
+        throw new UnsupportedOperationException();
+    }
 }

app/src/main/java/org/isoron/uhabits/notifications/NotificationTray.java

@@ -88,16 +88,25 @@ public class NotificationTray
     public void onCommandExecuted(@NonNull Command command,
                                   @Nullable Long refreshKey)
     {
-        if (!(command instanceof ToggleRepetitionCommand)) return;
+        if (command instanceof ToggleRepetitionCommand)
-
+        {
-        ToggleRepetitionCommand toggleCommand =
+            ToggleRepetitionCommand toggleCmd =
                 (ToggleRepetitionCommand) command;
 
-        Habit habit = toggleCommand.getHabit();
+            Habit habit = toggleCmd.getHabit();
             if (habit.getCheckmarks().getTodayValue() != Checkmark.UNCHECKED)
                 cancel(habit);
         }
 
+        if (command instanceof DeleteHabitsCommand)
+        {
+            DeleteHabitsCommand deleteCommand = (DeleteHabitsCommand) command;
+            List<Habit> deleted = deleteCommand.getHabits();
+            for(Habit habit : deleted)
+                cancel(habit);
+        }
+    }
+
     @Override
     public void onNotificationsChanged()
     {