Fixed text element changed event

I18N Commander/UI WinForms/AppEvents.cs

@@ -17,10 +17,10 @@ internal static class AppEvents
     #region Event: Text element was changed
 
     // Text element changed event which can be subscribed:
-    internal static event EventHandler<TextElement> WhenTextElementChanged;
+    internal static event EventHandler<TextElement?> WhenTextElementChanged;
     
     // Method to raise the text element changed event:
-    internal static void TextElementChanged(TextElement textElement) => WhenTextElementChanged?.Invoke(null, textElement);
+    internal static void TextElementChanged(TextElement? textElement) => WhenTextElementChanged?.Invoke(null, textElement);
 
     #endregion
 }

I18N Commander/UI WinForms/Components/TextElements.cs

@@ -182,13 +182,20 @@ public partial class TextElements : UserControl
 
     private async void listTextElements_ItemSelectionChanged(object sender, ListViewItemSelectionChangedEventArgs e)
     {
-        // Load the text element:
+        if (e.IsSelected)
+        {
+            // Get the text element's id:
             var selectedTextElementId = (int)e.Item.Tag;
+            
+            // Load the text element:
             this.currentTextElement = await TextElementProcessor.LoadTextElement(selectedTextElementId);
 
             // Fire the event:
             AppEvents.TextElementChanged(this.currentTextElement);
         }
+        else
+            AppEvents.TextElementChanged(null);
+    }
 
     private async void textBoxFilter_KeyUp(object sender, KeyEventArgs e) => await this.LoadTextElements();
 }

I18N Commander/UI WinForms/Components/Translation.cs

@@ -63,6 +63,18 @@ public sealed partial class Translation : UserControl
         this.isLoading = false;
     }
 
+    public void Clear()
+    {
+        this.isLoading = true;
+        
+        this.currentTranslationId = -1;
+        this.textBox.Text = string.Empty;
+        this.textBox.Multiline = true;
+        this.Height = 280;
+        
+        this.isLoading = false;
+    }
+
     private async void textBox_TextChanged(object sender, EventArgs e)
     {
         if(this.isLoading)

I18N Commander/UI WinForms/Components/Translations.cs

@@ -1,22 +1,58 @@
 using Processor;
+using Timer = System.Timers.Timer;
 
 namespace UI_WinForms.Components;
 
 public partial class Translations : UserControl
 {
     private readonly Dictionary<string, Translation> translationComponents = new();
+    private readonly Timer clearTimer;
 
     public Translations()
     {
         this.InitializeComponent();
+        this.Enabled = false;
+        this.clearTimer = new Timer
+        {
+            Enabled = false,
+            Interval = 600, // ms
+            AutoReset = false,
+        };
+        this.clearTimer.Elapsed += (sender, args) => this.ClearTranslations();
         this.Load += async (sender, args) => await this.SetupTranslations();
         AppEvents.WhenTextElementChanged += async (sender, textElement) =>
         {
+            if(textElement is null)
+            {
+                this.clearTimer.Start();
+                return;
+            }
+            
+            this.clearTimer.Stop();
+            if (!this.Enabled)
+                this.Enabled = true;
+            
             var allTranslations = await TranslationProcessor.GetTranslations(textElement);
             foreach (var translation in allTranslations)
                 if (this.translationComponents.ContainsKey(translation.Culture))
                     await this.translationComponents[translation.Culture].Configure(translation);
         };
+        
+        AppEvents.WhenSectionChanged += (sender, section) => this.ClearTranslations();
+    }
+    
+    private void ClearTranslations()
+    {
+        // Perform UI changes on the UI thread:
+        if (this.InvokeRequired)
+        {
+            this.Invoke(this.ClearTranslations);
+            return;
+        }
+
+        this.Enabled = false;
+        foreach (var (_, translation) in this.translationComponents)
+            translation.Clear();
     }
 
     private async Task SetupTranslations()