add next & previous controls

Author: cjakeman

Source/Menu/MainForm.Designer.cs

@@ -1443,6 +1443,13 @@ void comboBoxTimetable_EnabledChanged(object sender, EventArgs e)
         }
 
         #region NotificationPages
+        public int CurrentNotificationNo = 0;
+        private bool firstVisible = true;
+        private bool previousVisible = false;
+        private bool lastVisible = false;
+        private bool nextVisible = true;
+
+
         private void pbNotificationsNone_Click(object sender, EventArgs e)
         {
             ToggleNotificationPages();
@@ -1473,7 +1480,7 @@ private void ToggleNotificationPages()
 
         private void FiddleNewNotificationPageCount()
         {
-            NotificationManager.LastPageViewed = 1;
+            //NotificationManager.LastPageViewed = 1;
             UpdateNotificationPageAlert();
         }
 
@@ -1490,7 +1497,7 @@ void ShowNotificationPages()
         {
             Win32.LockWindowUpdate(Handle);
             ClearPanel();
-            NotificationManager.PopulatePageList();
+            NotificationManager.PopulatePage();
             var notificationPage = GetCurrentNotificationPage();
             notificationPage.FlowNDetails();
             Win32.LockWindowUpdate(IntPtr.Zero);
@@ -1502,12 +1509,23 @@ void ShowNotificationPages()
         /// <returns></returns>
         NotificationPage GetCurrentNotificationPage()
         {
-            return NotificationManager.PageList[0];
+            return NotificationManager.Page;
         }
 
-        public NotificationPage CreateNotificationPage(Notifications notifications)
+        /// <summary>
+        /// Returns a new notificationPage with default images and label
+        /// </summary>
+        /// <returns></returns>
+        public NotificationPage CreateNotificationPage()
+        // Located in MainForm to get access to MainForm.Resources
         {
-            return new NotificationPage(this, panelDetails);
+            var previousImage = (Image)Resources.GetObject("Notification_previous");
+            var nextImage = (Image)Resources.GetObject("Notification_next");
+            var firstImage = (Image)Resources.GetObject("Notification_first");
+            var lastImage = (Image)Resources.GetObject("Notification_last");
+            var pageCount = $"{CurrentNotificationNo + 1}/{NotificationManager.Notifications.NotificationList.Count}";
+            return new NotificationPage(this, panelDetails, nextImage, previousImage, firstImage, lastImage, pageCount,
+                previousVisible, firstVisible, nextVisible, lastVisible);
         }
 
         // 3 should be enough, but is there a way to get unlimited buttons?
@@ -1524,6 +1542,51 @@ public void Button2_Click(object sender, EventArgs e)
             GetCurrentNotificationPage().DoButton(UpdateManager, 2);
         }
 
+        public void Next_Click(object sender, EventArgs e)
+        {
+            ChangePage(1);
+            // GetCurrentNotificationPage().DoNext(1);
+        }
+
+        public void Previous_Click(object sender, EventArgs e)
+        {
+            ChangePage(-1);
+            //GetCurrentNotificationPage().DoNext(-1);
+        }
+
+        private void ChangePage(int step)
+        {
+            SetVisibility(step);
+            CurrentNotificationNo += step;
+            ShowNotificationPages();
+        }
+
+        private void SetVisibility(int step)
+        {
+            if (step < 0)
+            {
+                if (CurrentNotificationNo + step <= 0)
+                {
+                    previousVisible = false;
+                    firstVisible = true;
+                    return;
+                }
+            }
+            else
+            {
+                if (CurrentNotificationNo + step >= NotificationManager.Notifications.NotificationList.Count - 1)
+                {
+                    nextVisible = false;
+                    lastVisible = true;
+                    return;
+                }
+            }
+            nextVisible = true;
+            lastVisible = false;
+            previousVisible = true;
+            firstVisible = false;
+        }
+
         #endregion NotificationPages
     }
 }

Source/Menu/MainForm.cs

@@ -34,6 +34,14 @@
 //TODO Add caching of criteria
 //TODO Add "includeIf" for individual notifications
 
+// Notifications are read only once as a background task at start into NotificationList.
+// Every time the notifications page is re-visited, the options may have changed, so
+// the visibility of each notification in NotificationList is re-assessed. Also its date.
+// A SortedPageList is created which contains a list of indexes for the notifications to be shown sorted as latest first.
+// Every time the notifications page is re-visited or the page is incremented up or down,
+// the current notification is re-assessed and
+// the panel is re-loaded with Controls for the current page.
+
 namespace ORTS
 {
     class NotificationManager
@@ -44,17 +52,18 @@ class NotificationManager
         // We don't track the reading of each notification but set the NewNotificationCount = 0 after the last of the new ones has been read.
         public int NewPageCount = 1;
         public int LastPageViewed = 0;
-        public int Index = 0;
+        //public int Index = 0;
 
         public Notifications Notifications;
-        public List<NotificationPage> PageList = new List<NotificationPage>();
         private Exception Error;
         private Dictionary<string, string> ParameterDictionary;
 
         private readonly MainForm MainForm; // Needed so we can add controls to the NotificationPage
         private readonly UpdateManager UpdateManager;
         private readonly UserSettings Settings;
 
+        public NotificationPage Page { get; private set; }
+
         public NotificationManager(MainForm mainForm, UpdateManager updateManager, UserSettings settings) 
         { 
             MainForm = mainForm;
@@ -78,7 +87,7 @@ public void CheckNotifications()
                 ReplaceParameters();
                 LogParameters();
 
-                PopulatePageList();
+                PopulatePage();
                 ArePagesVisible = false;
             }
             catch (WebException ex)
@@ -135,24 +144,22 @@ private string GetRemoteJson()
             return client.DownloadString(new Uri("https://wepp.co.uk/openrails/notifications2/menu.json"));
         }
 
-        public void PopulatePageList()
+        public void PopulatePage()
         {
-            SetUpdateNotificationPage();
-
-            var NotificationPage = PageList.LastOrDefault();
-            new NTextControl(NotificationPage, "").Add();
-            new NTextControl(NotificationPage, "(Toggle icon to hide these notifications.)").Add();
+            Page = UpdateNotificationPage();
+            new NTextControl(Page, "").Add();
+            new NTextControl(Page, "(Toggle icon to hide these notifications.)").Add();
         }
 
         /// <summary>
         /// Ultimately there will be a list of notifications downloaded from https://static.openrails.org/api/notifications/menu.json .
         /// Until then, there is a single notification announcing either that a new update is available or the installation is up to date.
         /// </summary>
-        private void SetUpdateNotificationPage()
+        private NotificationPage UpdateNotificationPage()
         {
+            var page = MainForm.CreateNotificationPage();
+
             MainForm.UpdateNotificationPageAlert();
-            PageList.Clear();
-            var page = MainForm.CreateNotificationPage(Notifications);
 
             if (UpdateManager.LastCheckError != null || Error != null)
             {
@@ -173,24 +180,23 @@ private void SetUpdateNotificationPage()
                 new NTextControl(page, "Is your Internet connected?").Add();
 
                 new NRetryControl(page, "Retry", 140, "Try again to fetch notifications", MainForm).Add();
-                PageList.Add(page);
-                return;
             }
 
             NewPageCount = 1;
             var list = Notifications.NotificationList;
-            var n = list[Index];
+            var n = list[MainForm.CurrentNotificationNo];
             LogNotification(n);
 
-            var skipPage = false;
-            new NTitleControl(page, Index + 1, list.Count, n.Date, n.Title).Add();
+            //var skipPage = false;
+            new NTitleControl(page, MainForm.CurrentNotificationNo + 1, list.Count, n.Date, n.Title).Add();
 
             // Check constraints for each item
-            foreach(var item in n.ItemList)
+            foreach (var item in n.ItemList)
             {
                 if (AreChecksMet(item)) AddItemToPage(page, item);
             }
-            if (skipPage == false) PageList.Add(page);
+
+            return page;
         }
 
         #region Process Criteria
@@ -337,9 +343,6 @@ public void ReplaceParameters()
             {
                 n.Title = ReplaceParameter(n.Title);
                 n.Date = ReplaceParameter(n.Date);
-                //n.PrefixItemList?.ForEach(item => ReplaceItemParameter(item));
-                //n.Met.ItemList?.ForEach(item => ReplaceItemParameter(item));
-                //n.SuffixItemList?.ForEach(item => ReplaceItemParameter(item));
                 n.ItemList?.ForEach(item => ReplaceItemParameter(item));
             }
             foreach (var list in Notifications.CheckList)