From 192530d8a5024db64a6f6e4c3129a3127c588c7d Mon Sep 17 00:00:00 2001
From: Paul Licameli <paul.licameli@audacityteam.org>
Date: Mon, 1 Jul 2019 08:11:25 -0400
Subject: [PATCH] Free ScrubbingToolBar from cycles...

... by having it update itself in idle time, not needing a push from Scrubber

Shrinking that remnant of the big strongly connected component to 6
---
 src/toolbars/ScrubbingToolBar.cpp | 8 +++++++-
 src/toolbars/ScrubbingToolBar.h   | 2 ++
 src/tracks/ui/Scrubbing.cpp       | 5 -----
 3 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/src/toolbars/ScrubbingToolBar.cpp b/src/toolbars/ScrubbingToolBar.cpp
index 988fe1103..4fe092ec7 100644
--- a/src/toolbars/ScrubbingToolBar.cpp
+++ b/src/toolbars/ScrubbingToolBar.cpp
@@ -52,6 +52,7 @@ EVT_COMMAND_RANGE( STBFirstButton,
                   STBFirstButton + STBNumButtons - 1,
                   wxEVT_COMMAND_BUTTON_CLICKED,
                   ScrubbingToolBar::OnButton )
+EVT_IDLE( ScrubbingToolBar::OnIdle )
 END_EVENT_TABLE()
 
 //Standard contructor
@@ -223,7 +224,6 @@ void ScrubbingToolBar::EnableDisableButtons()
    seekButton->SetEnabled(true);
 
    AudacityProject *p = &mProject;
-   if (!p) return;
 
    auto &scrubber = Scrubber::Get( *p );
    const auto canScrub = scrubber.CanScrub();
@@ -262,6 +262,12 @@ void ScrubbingToolBar::EnableDisableButtons()
    scrubber.CheckMenuItems();
 }
 
+void ScrubbingToolBar::OnIdle( wxIdleEvent &evt )
+{
+   evt.Skip();
+   EnableDisableButtons();
+}
+
 static RegisteredToolbarFactory factory{ ScrubbingBarID,
    []( AudacityProject &project ){
       return ToolBar::Holder{ safenew ScrubbingToolBar{ project } }; }
diff --git a/src/toolbars/ScrubbingToolBar.h b/src/toolbars/ScrubbingToolBar.h
index ce13a3804..fc692aea3 100644
--- a/src/toolbars/ScrubbingToolBar.h
+++ b/src/toolbars/ScrubbingToolBar.h
@@ -72,6 +72,8 @@ private:
    wxImage *downImage;
    wxImage *hiliteImage;
 
+   void OnIdle( wxIdleEvent &evt );
+
 public:
 
    DECLARE_CLASS(ScrubbingToolBar)
diff --git a/src/tracks/ui/Scrubbing.cpp b/src/tracks/ui/Scrubbing.cpp
index b4a2e5059..4de7ce16f 100644
--- a/src/tracks/ui/Scrubbing.cpp
+++ b/src/tracks/ui/Scrubbing.cpp
@@ -30,7 +30,6 @@ Paul Licameli split from TrackPanel.cpp
 #include "../../prefs/PlaybackPrefs.h"
 #include "../../prefs/TracksPrefs.h"
 #include "../../toolbars/ControlToolBar.h"
-#include "../../toolbars/ScrubbingToolBar.h"
 #include "../../toolbars/ToolManager.h"
 
 #undef USE_TRANSCRIPTION_TOOLBAR
@@ -1120,10 +1119,6 @@ void Scrubber::OnScrubOrSeek(bool seek)
    auto &ruler = AdornedRulerPanel::Get( *mProject );
    // Update button images
    ruler.UpdateButtonStates();
-
-   auto scrubbingToolBar = &ScrubbingToolBar::Get( *mProject );
-   scrubbingToolBar->EnableDisableButtons();
-   scrubbingToolBar->RegenerateTooltips();
 }
 
 void Scrubber::OnScrub(const CommandContext&)