Add option to show only installed themes

Author: t1m0thyj

src/JsonConfig.cs

@@ -44,6 +44,7 @@ public class AppConfig : INotifyPropertyChanged
         public string lastShuffleTime { get; set; }
         public string[] shuffleHistory { get; set; }
         public string[] favoriteThemes { get; set; }
+        public bool showInstalledOnly { get; set; }
 
         // General settings
         public string language { get; set; }

src/ThemeDialog.Designer.cs

@@ -350,17 +350,24 @@ private void contextMenuStrip1_Opening(object sender, CancelEventArgs e)
         {
             var hitTestInfo = listView1.HitTest(listView1.PointToClient(Cursor.Position));
             int itemIndex = hitTestInfo.Item?.Index ?? -1;
+            string themeId = null;
+            ThemeConfig theme = null;
 
-            if (itemIndex <= 0)
+            if (itemIndex < 0)
             {
                 e.Cancel = true;
                 return;
             }
+            else if (itemIndex > 0)
+            {
+                themeId = (string)listView1.Items[itemIndex].Tag;
+                theme = ThemeManager.themeSettings.Find(t => t.themeId == themeId);
+            }
 
-            string themeId = (string)listView1.Items[itemIndex].Tag;
-            ThemeConfig theme = ThemeManager.themeSettings.Find(t => t.themeId == themeId);
             bool isWindowsTheme = themeId == DefaultThemes.GetWindowsTheme()?.themeId;
-            contextMenuStrip1.Items[1].Enabled = ThemeManager.IsThemeDownloaded(theme) && !isWindowsTheme;
+            contextMenuStrip1.Items[0].Enabled = itemIndex > 0;
+            contextMenuStrip1.Items[1].Enabled = theme != null && ThemeManager.IsThemeDownloaded(theme) &&
+                !isWindowsTheme;
 
             if (JsonConfig.settings.favoriteThemes == null ||
                 !JsonConfig.settings.favoriteThemes.Contains(themeId))
@@ -372,14 +379,17 @@ private void contextMenuStrip1_Opening(object sender, CancelEventArgs e)
                 contextMenuStrip1.Items[0].Text = _("Remove from favorites");
             }
 
-            if (ThemeManager.defaultThemes.Contains(themeId) || isWindowsTheme)
+            if (themeId == null || ThemeManager.defaultThemes.Contains(themeId) || isWindowsTheme)
             {
                 contextMenuStrip1.Items[1].Text = _("Delete");
             }
             else
             {
                 contextMenuStrip1.Items[1].Text = _("Delete permanently");
             }
+
+            contextMenuStrip1.Items[3].Text = _("Show only installed themes");
+            (contextMenuStrip1.Items[3] as ToolStripMenuItem).Checked = JsonConfig.settings.showInstalledOnly;
         }
 
         private void favoriteThemeMenuItem_Click(object sender, EventArgs e)
@@ -424,6 +434,11 @@ private void deleteThemeMenuItem_Click(object sender, EventArgs e)
             }
         }
 
+        private void showInstalledMenuItem_Click(object sender, EventArgs e)
+        {
+            ThemeDialogUtils.ToggleShowInstalledOnly(listView1, !JsonConfig.settings.showInstalledOnly);
+        }
+
         private void OnDownloadDialogClosed(object sender, FormClosedEventArgs e)
         {
             if (e.CloseReason == CloseReason.UserClosing &&

src/ThemeDialog.cs

@@ -72,6 +72,11 @@ internal static void LoadThemes(List<ThemeConfig> themes, ListView listView, The
 
             foreach (ThemeConfig theme in themes.ToList())
             {
+                if (JsonConfig.settings.showInstalledOnly && !ThemeManager.IsThemeDownloaded(theme))
+                {
+                    continue;
+                }
+
                 try
                 {
                     using (Image thumbnailImage = ThemeThumbLoader.GetThumbnailImage(theme, thumbnailSize, true))
@@ -221,5 +226,31 @@ internal static bool DeleteTheme(ThemeConfig theme, ListView listView, int itemI
 
             return result == DialogResult.Yes;
         }
+
+        internal static void ToggleShowInstalledOnly(ListView listView, bool newValue)
+        {
+            JsonConfig.settings.showInstalledOnly = newValue;
+            if (newValue)
+            {
+                foreach (ListViewItem item in listView.Items)
+                {
+                    if (item.Index > 0)
+                    {
+                        string themeId = (string)item.Tag;
+                        ThemeConfig theme = ThemeManager.themeSettings.Find(t => t.themeId == themeId);
+                        if (!ThemeManager.IsThemeDownloaded(theme))
+                        {
+                            listView.Items.Remove(item);
+                            listView.LargeImageList.Images[item.ImageIndex].Dispose();
+                        }
+                    }
+                }
+            }
+            else
+            {
+                LoadThemes(ThemeManager.themeSettings.Where(theme => !ThemeManager.IsThemeDownloaded(theme)).ToList(),
+                    listView, new ThemeLoadOpts());
+            }
+        }
     }
 }