Fix #50

Author: chuongmep

AddInManager/App.cs

@@ -37,6 +37,7 @@ public Result OnStartup(UIControlledApplication application)
 #if !(R25 || R26 || R27)
         AppDomain.CurrentDomain.AssemblyResolve += CurrentDomain_AssemblyResolve;
 #endif
+        CodeListener.EnsureRegistered();
         CreateRibbonPanel(application);
         application.ControlledApplication.DocumentClosed += DocumentClosed;
         DefaultSetting.Version += VersionChecker.CurrentVersion;

AddInManager/Command/AddInManagerCommand.cs

@@ -11,9 +11,7 @@ public class AddInManagerManual : IExternalCommand
 {
     public Result Execute(ExternalCommandData commandData, ref string message, ElementSet elements)
     {
-        Trace.Listeners.Clear();
-        CodeListener codeListener = new CodeListener();
-        Trace.Listeners.Add(codeListener);
+        CodeListener.EnsureRegistered();
         StaticUtil.RegenOption = RegenerationOption.Manual;
         StaticUtil.TransactMode = TransactionMode.Manual;
         Result result = AddinManagerBase.Instance.ExecuteCommand(commandData, ref message, elements, false);

AddInManager/Model/CodeListener.cs

@@ -5,6 +5,22 @@ namespace RevitAddinManager.Model;
 
 public class CodeListener : TraceListener
 {
+    private static readonly object SyncRoot = new object();
+
+    public static void EnsureRegistered()
+    {
+        lock (SyncRoot)
+        {
+            if (Trace.Listeners.OfType<CodeListener>().Any())
+            {
+                return;
+            }
+
+            Trace.Listeners.Add(new CodeListener());
+            Trace.AutoFlush = true;
+        }
+    }
+
     public override void Write(string message)
     {
         WriteMessage(message);

Test/DebugTraceCommnad.cs

@@ -0,0 +1,16 @@
+using System.Diagnostics;
+using Autodesk.Revit.Attributes;
+using Autodesk.Revit.DB;
+using Autodesk.Revit.UI;
+
+namespace Test;
+
+[Transaction(TransactionMode.Manual)]
+public class DebugTraceCommnad : IExternalCommand
+{
+    public Result Execute(ExternalCommandData commandData, ref string message, ElementSet elements)
+    {
+        Trace.Write("hello");
+        return Result.Succeeded;
+    }
+}