Fixed several possible issues with PPC start/stop dyeing buttons visibility.

Prevented navigation conflicts raised by impatient users.

3 files changed, 30 insertions, 1 deletions

diff --git a/Software/Visual_Studio/PPC/Modules/Tango.PPC.Jobs/ViewModels/JobSummeryViewVM.cs b/Software/Visual_Studio/PPC/Modules/Tango.PPC.Jobs/ViewModels/JobSummeryViewVM.cs
index 365075d4a..d6eb3bc63 100644
--- a/Software/Visual_Studio/PPC/Modules/Tango.PPC.Jobs/ViewModels/JobSummeryViewVM.cs
+++ b/Software/Visual_Studio/PPC/Modules/Tango.PPC.Jobs/ViewModels/JobSummeryViewVM.cs
@@ -26,6 +26,7 @@ namespace Tango.PPC.Jobs.ViewModels
     {
         private ObservablesContext _context;
         private bool _canStartJob;
+        private bool _startingJob;
 
         private bool _isPreparingJob;
         /// <summary>
@@ -96,12 +97,17 @@ namespace Tango.PPC.Jobs.ViewModels
         /// </summary>
         private async void StartJob()
         {
+            if (_startingJob) return;
+
+            _startingJob = true;
+
             try
             {
                 LogManager.Log("Start job command pressed. Starting job and navigating to job progress view...");
 
                 await PrintingManager.Print(Job, _context);
                 await NavigationManager.NavigateTo<JobsModule>(false, nameof(JobProgressView));
+                _startingJob = false;
             }
             catch (InsufficientLiquidQuantityException)
             {
@@ -112,6 +118,10 @@ namespace Tango.PPC.Jobs.ViewModels
                 LogManager.Log(ex, "Could not start the current job.");
                 await NotificationProvider.ShowError($"{ex.Message}");
             }
+            finally
+            {
+                _startingJob = false;
+            }
         }
 
         /// <summary>
diff --git a/Software/Visual_Studio/PPC/Modules/Tango.PPC.Jobs/ViewModels/JobViewVM.cs b/Software/Visual_Studio/PPC/Modules/Tango.PPC.Jobs/ViewModels/JobViewVM.cs
index efaf98966..665847081 100644
--- a/Software/Visual_Studio/PPC/Modules/Tango.PPC.Jobs/ViewModels/JobViewVM.cs
+++ b/Software/Visual_Studio/PPC/Modules/Tango.PPC.Jobs/ViewModels/JobViewVM.cs
@@ -56,6 +56,7 @@ namespace Tango.PPC.Jobs.ViewModels
         private ActionTimer _volumeConversionTimer;
         private IColorConverter _converter;
         private string _current_job_string;
+        private bool startingJob = false;
 
         #region Properties
 
@@ -545,7 +546,7 @@ namespace Tango.PPC.Jobs.ViewModels
             }
             catch (Exception ex)
             {
-                LogManager.Log(ex, $"Error loading job '{_job_to_load.Name}'");
+                LogManager.Log(ex, $"Error loading job '{(_job_to_load != null ? _job_to_load.Name : "null")}'");
                 await NotificationProvider.ShowError("An error occurred while trying to load the selected job.");
                 _can_navigate_back = true;
                 await NavigationManager.NavigateBack();
@@ -647,11 +648,16 @@ namespace Tango.PPC.Jobs.ViewModels
         /// </summary>
         private async void StartJob()
         {
+            if (startingJob) return;
+
             try
             {
+                Debug.WriteLine("Job Starting...");
+                startingJob = true;
                 LogManager.Log("Start job command pressed. Starting job and navigating to job progress view...");
                 var handler = await PrintingManager.Print(Job, _db);
                 await NavigationManager.NavigateTo<JobsModule>(nameof(JobProgressView));
+                startingJob = false;
             }
             catch (InsufficientLiquidQuantityException)
             {
@@ -662,6 +668,10 @@ namespace Tango.PPC.Jobs.ViewModels
                 LogManager.Log(ex, "Could not start the current job.");
                 await NotificationProvider.ShowError($"{ex.Message}.");
             }
+            finally
+            {
+                startingJob = false;
+            }
         }
 
         /// <summary>
diff --git a/Software/Visual_Studio/PPC/Tango.PPC.UI/Navigation/DefaultNavigationManager.cs b/Software/Visual_Studio/PPC/Tango.PPC.UI/Navigation/DefaultNavigationManager.cs
index 3502648d4..7c71ef3d0 100644
--- a/Software/Visual_Studio/PPC/Tango.PPC.UI/Navigation/DefaultNavigationManager.cs
+++ b/Software/Visual_Studio/PPC/Tango.PPC.UI/Navigation/DefaultNavigationManager.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Linq;
 using System.Reflection;
 using System.Runtime.CompilerServices;
@@ -501,6 +502,10 @@ namespace Tango.PPC.UI.Navigation
 
         private void NotifyOnBeforeNavigated(object fromVM, object toVM)
         {
+            IsBackEnabled = false;
+
+            if (fromVM == toVM) return;
+
             if (fromVM is PPCViewModel)
             {
                 (fromVM as PPCViewModel)?.OnBeforeNavigatedFrom();
@@ -514,6 +519,10 @@ namespace Tango.PPC.UI.Navigation
 
         private void NotifyOnNavigated(object fromVM, object toVM)
         {
+            IsBackEnabled = true;
+
+            if (fromVM == toVM) return;
+
             if (fromVM is PPCViewModel)
             {
                 (fromVM as PPCViewModel)?.OnNavigatedFrom();