From 19acf89d2a2f33ea98c152248d2b6914399e66f7 Mon Sep 17 00:00:00 2001
From: Leland Lucius <github@homerow.net>
Date: Wed, 27 May 2015 08:50:00 -0500
Subject: [PATCH] Fix for bug #869

---
 src/effects/Effect.cpp | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/src/effects/Effect.cpp b/src/effects/Effect.cpp
index ab3644037..7d3bd42f7 100755
--- a/src/effects/Effect.cpp
+++ b/src/effects/Effect.cpp
@@ -2522,21 +2522,24 @@ void Effect::Preview(bool dryOnly)
       if (token) {
          int previewing = eProgressSuccess;
 
-         mProgress = new ProgressDialog(GetName(),
-                                       _("Previewing"), pdlgHideCancelButton);
+         // The progress dialog must be deleted before stopping the stream
+         // to allow events to flow to the app during StopStream processing.
+         // The progress dialog blocks these events.
+         ProgressDialog *progress =
+            new ProgressDialog(GetName(), _("Previewing"), pdlgHideCancelButton);
 
          while (gAudioIO->IsStreamActive(token) && previewing == eProgressSuccess) {
             ::wxMilliSleep(100);
-            previewing = mProgress->Update(gAudioIO->GetStreamTime() - mT0, mT1);
+            previewing = progress->Update(gAudioIO->GetStreamTime() - mT0, mT1);
          }
+
+         delete progress;
+
          gAudioIO->StopStream();
 
          while (gAudioIO->IsBusy()) {
             ::wxMilliSleep(100);
          }
-
-         delete mProgress;
-         mProgress = NULL;
       }
       else {
          wxMessageBox(_("Error while opening sound device. Please check the playback device settings and the project sample rate."),