From 2d0394796ed0dad359da120f4d82fdf8ec3b8431 Mon Sep 17 00:00:00 2001
From: Paul Licameli <paul.licameli@audacityteam.org>
Date: Sun, 7 Feb 2021 21:17:45 -0500
Subject: [PATCH] Facade class for basic UI, injection of a wxWidgets
 implementation...

... but none of the methods is defined yet.

The intention is to inject dependencies on wxWidgets (or other) toolkit so that
lower-level files have less build dependency on wxCore classes or on the
event loop.

Original commit: d20cf012556a819e68515d86bb66a2c047007539

Signed-off-by: Panagiotis Vasilopoulos <hello@alwayslivid.com>
---
 libraries/CMakeLists.txt              |    1 +
 libraries/lib-basic-ui/BasicUI.cpp    |   25 +
 libraries/lib-basic-ui/BasicUI.h      |   47 ++
 libraries/lib-basic-ui/CMakeLists.txt |   23 +
 src/AudacityApp.cpp                   |   24 +-
 src/CMakeLists.txt                    | 1082 +++++++++++++++++++++----
 src/widgets/wxWidgetsBasicUI.cpp      |   12 +
 src/widgets/wxWidgetsBasicUI.h        |   23 +
 8 files changed, 1066 insertions(+), 171 deletions(-)
 create mode 100644 libraries/lib-basic-ui/BasicUI.cpp
 create mode 100644 libraries/lib-basic-ui/BasicUI.h
 create mode 100644 libraries/lib-basic-ui/CMakeLists.txt
 create mode 100644 src/widgets/wxWidgetsBasicUI.cpp
 create mode 100644 src/widgets/wxWidgetsBasicUI.h

diff --git a/libraries/CMakeLists.txt b/libraries/CMakeLists.txt
index 21c06a373..ebb1f5fc8 100644
--- a/libraries/CMakeLists.txt
+++ b/libraries/CMakeLists.txt
@@ -7,6 +7,7 @@ set( LIBRARIES
    lib-strings
    lib-utility
    lib-components
+   lib-basic-ui
 )
 
 foreach( LIBRARY ${LIBRARIES} )
diff --git a/libraries/lib-basic-ui/BasicUI.cpp b/libraries/lib-basic-ui/BasicUI.cpp
new file mode 100644
index 000000000..bda996756
--- /dev/null
+++ b/libraries/lib-basic-ui/BasicUI.cpp
@@ -0,0 +1,25 @@
+/*!********************************************************************
+
+Audacity: A Digital Audio Editor
+
+@file BasicUI.cpp
+
+Paul Licameli
+
+**********************************************************************/
+#include "BasicUI.h"
+
+namespace  BasicUI {
+Services::~Services() = default;
+
+static Services *theInstance = nullptr;
+
+Services *Get() { return theInstance; }
+
+Services *Install(Services *pInstance)
+{
+   auto result = theInstance;
+   theInstance = pInstance;
+   return result;
+}
+}
diff --git a/libraries/lib-basic-ui/BasicUI.h b/libraries/lib-basic-ui/BasicUI.h
new file mode 100644
index 000000000..2a9c89b28
--- /dev/null
+++ b/libraries/lib-basic-ui/BasicUI.h
@@ -0,0 +1,47 @@
+/*!********************************************************************
+
+Audacity: A Digital Audio Editor
+
+@file BasicUI.h
+@brief Toolkit-neutral facade for basic user interface services
+
+Paul Licameli
+
+**********************************************************************/
+#ifndef __AUDACITY_BASIC_UI__
+#define __AUDACITY_BASIC_UI__
+
+namespace BasicUI {
+
+//! @name Types used in the Services interface
+//! @{
+
+//! @}
+
+//! Abstract class defines a few user interface services, not mentioning particular toolkits
+/*! The intention is that the application supplies a concrete implementation at
+ startup.  Most code will not use this class directly, but call the inline
+ functions that follow. */
+class BASIC_UI_API Services {
+public:
+   virtual ~Services();
+};
+
+//! Fetch the global instance, or nullptr if none is yet installed
+BASIC_UI_API Services *Get();
+
+//! Install an implementation; return the previously installed instance
+BASIC_UI_API Services *Install(Services *pInstance);
+
+/*! @name Functions that invoke global Services
+   These dispatch to the global Services, if supplied.  If none was supplied,
+   they are mostly no-ops, with exceptions as noted.  All should be called on
+   the main thread only, except as noted.
+ */
+//! @{
+
+//! @}
+}
+
+
+#endif
diff --git a/libraries/lib-basic-ui/CMakeLists.txt b/libraries/lib-basic-ui/CMakeLists.txt
new file mode 100644
index 000000000..c733d7f1e
--- /dev/null
+++ b/libraries/lib-basic-ui/CMakeLists.txt
@@ -0,0 +1,23 @@
+#[[
+This library defines a facade interface, BasicUI::Services, for a few basic
+interactions with the user, such as showing simple dialog boxes, and for
+enqueuing actions to the event loop, and yielding to to the event dispatcher.
+
+The interface makes no mention of classes in wxWidgets.  Using this library
+instead of making direct use of wxWidgets enlarges the parts of the program
+that are toolkit neutral.
+
+There is a global pointer to an instance of Services, and the main program is
+expected, at startup, to create a static instance of a subclass of Services and
+set the pointer.  If it does not, then calls to the non-member functions in
+namespace BasicUI are no-ops.
+]]#
+
+set( SOURCES
+   BasicUI.cpp
+   BasicUI.h
+)
+audacity_library( lib-basic-ui "${SOURCES}"
+   ""
+   "" ""
+)
diff --git a/src/AudacityApp.cpp b/src/AudacityApp.cpp
index 4fab923aa..f716588ef 100644
--- a/src/AudacityApp.cpp
+++ b/src/AudacityApp.cpp
@@ -110,6 +110,7 @@ It handles initialization and termination by subclassing wxApp.
 #include "tracks/ui/Scrubbing.h"
 #include "widgets/FileConfig.h"
 #include "widgets/FileHistory.h"
+#include "widgets/wxWidgetsBasicUI.h"
 
 #ifdef EXPERIMENTAL_EASY_CHANGE_KEY_BINDINGS
 #include "prefs/KeyConfigPrefs.h"
@@ -975,17 +976,22 @@ bool AudacityApp::OnInit() {
     // Ensure we have an event loop during initialization
     wxEventLoopGuarantor eventLoop;
 
-    // Fire up SQLite
-    if (!ProjectFileIO::InitializeSQL())
-        this->CallAfter([] {
-        ::AudacityMessageBox(
-            XO("SQLite library failed to initialize.  Audacity cannot continue."));
-        QuitAudacity(true);
-                        });
+   // Inject basic GUI services behind the facade
+   {
+      static wxWidgetsBasicUI uiServices;
+      (void)BasicUI::Install(&uiServices);
+   }
 
+   // Fire up SQLite
+   if ( !ProjectFileIO::InitializeSQL() )
+      this->CallAfter([]{
+         ::AudacityMessageBox(
+            XO("SQLite library failed to initialize.  Audacity cannot continue.") );
+         QuitAudacity( true );
+      });
 
-    // cause initialization of wxWidgets' global logger target
-    (void)AudacityLogger::Get();
+   // cause initialization of wxWidgets' global logger target
+   (void)AudacityLogger::Get();
 
 #if defined(__WXMAC__)
     // Disable window animation
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 8e91f5ff6..a3fd8a369 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -409,168 +409,926 @@ list( APPEND SOURCES PRIVATE
   commands/Validators.h
 )
 
-# ~~~
-# Effects source files
-# ~~~
-list( APPEND SOURCES PRIVATE
-  # Built-in effects
-  effects/Amplify.cpp
-  effects/Amplify.h
-  effects/AutoDuck.cpp
-  effects/AutoDuck.h
-  effects/BassTreble.cpp
-  effects/BassTreble.h
-  effects/Biquad.cpp
-  effects/Biquad.h
-  effects/ChangePitch.cpp
-  effects/ChangePitch.h
-  effects/ChangeSpeed.cpp
-  effects/ChangeSpeed.h
-  effects/ChangeTempo.cpp
-  effects/ChangeTempo.h
-  effects/ClickRemoval.cpp
-  effects/ClickRemoval.h
-  effects/Compressor.cpp
-  effects/Compressor.h
-  effects/Contrast.cpp
-  effects/Contrast.h
-  effects/Distortion.cpp
-  effects/Distortion.h
-  effects/DtmfGen.cpp
-  effects/DtmfGen.h
-  effects/EBUR128.cpp
-  effects/EBUR128.h
-  effects/Echo.cpp
-  effects/Echo.h
-  effects/Effect.cpp
-  effects/Effect.h
-  effects/EffectManager.cpp
-  effects/EffectManager.h
-  effects/EffectUI.cpp
-  effects/EffectUI.h
-  effects/Equalization.cpp
-  effects/Equalization.h
-  effects/Equalization48x.cpp
-  effects/Equalization48x.h
-  effects/Fade.cpp
-  effects/Fade.h
-  effects/FindClipping.cpp
-  effects/FindClipping.h
-  effects/Generator.cpp
-  effects/Generator.h
-  effects/Invert.cpp
-  effects/Invert.h
-  effects/LoadEffects.cpp
-  effects/LoadEffects.h
-  effects/Loudness.cpp
-  effects/Loudness.h
-  effects/Noise.cpp
-  effects/Noise.h
-  effects/NoiseReduction.cpp
-  effects/NoiseReduction.h
-  effects/NoiseRemoval.cpp
-  effects/NoiseRemoval.h
-  effects/Normalize.cpp
-  effects/Normalize.h
-  effects/Paulstretch.cpp
-  effects/Paulstretch.h
-  effects/Phaser.cpp
-  effects/Phaser.h
-  effects/RealtimeEffectManager.cpp
-  effects/RealtimeEffectManager.h
-  effects/Repair.cpp
-  effects/Repair.h
-  effects/Repeat.cpp
-  effects/Repeat.h
-  effects/Reverb.cpp
-  effects/Reverb.h
-  effects/Reverb_libSoX.h
-  effects/Reverse.cpp
-  effects/Reverse.h
-  effects/SBSMSEffect.cpp
-  effects/SBSMSEffect.h
-  effects/ScienFilter.cpp
-  effects/ScienFilter.h
-  effects/ScoreAlignDialog.cpp
-  effects/ScoreAlignDialog.h
-  effects/Silence.cpp
-  effects/Silence.h
-  effects/SimpleMono.cpp
-  effects/SimpleMono.h
-  effects/SoundTouchEffect.cpp
-  effects/SoundTouchEffect.h
-  effects/StereoToMono.cpp
-  effects/StereoToMono.h
-  effects/TimeScale.cpp
-  effects/TimeScale.h
-  effects/TimeWarper.cpp
-  effects/TimeWarper.h
-  effects/ToneGen.cpp
-  effects/ToneGen.h
-  effects/TruncSilence.cpp
-  effects/TruncSilence.h
-  effects/TwoPassSimpleMono.cpp
-  effects/TwoPassSimpleMono.h
-  effects/Wahwah.cpp
-  effects/Wahwah.h
-  # VST effects
-  $<$<BOOL:${USE_VST}>:
-    effects/VST/VSTControl.h
-    effects/VST/VSTEffect.cpp
-    effects/VST/VSTEffect.h
-    effects/VST/aeffectx.h
-  >
-  $<$<AND:$<BOOL:${USE_VST}>,$<BOOL:${wxIS_GTK}>>:
-    effects/VST/VSTControlGTK.cpp
-    effects/VST/VSTControlGTK.h
-  >
-  $<$<AND:$<BOOL:${USE_VST}>,$<BOOL:${wxIS_WIN}>>:
-    effects/VST/VSTControlMSW.cpp
-    effects/VST/VSTControlMSW.h
-  >
-  $<$<AND:$<BOOL:${USE_VST}>,$<BOOL:${wxIS_MAC}>>:
-    effects/VST/VSTControlOSX.h
-    effects/VST/VSTControlOSX.mm
-  >
-  # Audio Unit effects
-  $<$<AND:$<BOOL:${USE_AUDIO_UNITS}>,$<BOOL:${wxIS_MAC}>>:
-    effects/audiounits/AUControl.h
-    effects/audiounits/AUControl.mm
-    effects/audiounits/AudioUnitEffect.cpp
-    effects/audiounits/AudioUnitEffect.h
-  >
-  # Ladspa effects
-  $<$<BOOL:${USE_LADSPA}>:
-    effects/ladspa/LadspaEffect.cpp
-    effects/ladspa/LadspaEffect.h
-    effects/ladspa/ladspa.h
-  >
-  # LV2 effects
-  $<$<BOOL:${USE_LV2}>:
-    effects/lv2/LV2Effect.cpp
-    effects/lv2/LV2Effect.h
-    effects/lv2/LoadLV2.cpp
-    effects/lv2/LoadLV2.h
-    effects/lv2/NativeWindow.h
-    effects/lv2/lv2_external_ui.h
-    effects/lv2/zix/common.h
-    effects/lv2/zix/ring.cpp
-    effects/lv2/zix/ring.h
-  >
-  # Nyquist effects
-  $<$<BOOL:${USE_NYQUIST}>:
-    effects/nyquist/LoadNyquist.cpp
-    effects/nyquist/LoadNyquist.h
-    effects/nyquist/Nyquist.cpp
-    effects/nyquist/Nyquist.h
-  >
-  # VAMP effects
-  $<$<BOOL:${USE_VAMP}>:
-    effects/vamp/LoadVamp.cpp
-    effects/vamp/LoadVamp.h
-    effects/vamp/VampEffect.cpp
-    effects/vamp/VampEffect.h
-  >
+list( APPEND SOURCES
+   PRIVATE
+      AColor.cpp
+      AColor.h
+      AColorResources.h
+      ActiveProjects.cpp
+      ActiveProjects.h
+      AboutDialog.cpp
+      AboutDialog.h
+      AdornedRulerPanel.cpp
+      AdornedRulerPanel.h
+      AllThemeResources.cpp
+      AllThemeResources.h
+      AttachedVirtualFunction.h
+      AudacityApp.cpp
+      AudacityApp.h
+      $<$<BOOL:${wxIS_MAC}>:AudacityApp.mm>
+      AudacityException.cpp
+      AudacityException.h
+      AudacityFileConfig.cpp
+      AudacityFileConfig.h
+      AudacityHeaders.cpp
+      AudacityHeaders.h
+      AudacityLogger.cpp
+      AudacityLogger.h
+      AudioIO.cpp
+      AudioIO.h
+      AudioIOBase.cpp
+      AudioIOBase.h
+      AudioIOListener.h
+      AutoRecoveryDialog.cpp
+      AutoRecoveryDialog.h
+      BatchCommandDialog.cpp
+      BatchCommandDialog.h
+      BatchCommands.cpp
+      BatchCommands.h
+      BatchProcessDialog.cpp
+      BatchProcessDialog.h
+      Benchmark.cpp
+      Benchmark.h
+      CellularPanel.cpp
+      CellularPanel.h
+      ClassicThemeAsCeeCode.h
+      ClientData.h
+      ClientDataHelpers.h
+      Clipboard.cpp
+      Clipboard.h
+      CommonCommandFlags.cpp
+      CommonCommandFlags.h
+      DarkThemeAsCeeCode.h
+      DBConnection.cpp
+      DBConnection.h
+      DeviceChange.cpp
+      DeviceChange.h
+      DeviceManager.cpp
+      DeviceManager.h
+      Diags.cpp
+      Diags.h
+      Dither.cpp
+      Dither.h
+      Envelope.cpp
+      Envelope.h
+      EnvelopeEditor.cpp
+      EnvelopeEditor.h
+      FFT.cpp
+      FFT.h
+      FFmpeg.cpp
+      FFmpeg.h
+      FileException.cpp
+      FileException.h
+      FileFormats.cpp
+      FileFormats.h
+      FileIO.cpp
+      FileIO.h
+      FileNames.cpp
+      FileNames.h
+      FreqWindow.cpp
+      FreqWindow.h
+      HelpText.cpp
+      HelpText.h
+      HiContrastThemeAsCeeCode.h
+      HistoryWindow.cpp
+      HistoryWindow.h
+      HitTestResult.h
+      ImageManipulation.cpp
+      ImageManipulation.h
+      InconsistencyException.cpp
+      InconsistencyException.h
+      InterpolateAudio.cpp
+      InterpolateAudio.h
+      KeyboardCapture.cpp
+      KeyboardCapture.h
+      LabelDialog.cpp
+      LabelDialog.h
+      LabelTrack.cpp
+      LabelTrack.h
+      LangChoice.cpp
+      LangChoice.h
+      Legacy.cpp
+      Legacy.h
+      LightThemeAsCeeCode.h
+      Lyrics.cpp
+      Lyrics.h
+      LyricsWindow.cpp
+      LyricsWindow.h
+      MacroMagic.h
+      Matrix.cpp
+      Matrix.h
+      Menus.cpp
+      Menus.h
+      Mix.cpp
+      Mix.h
+      MixerBoard.cpp
+      MixerBoard.h
+      ModuleManager.cpp
+      ModuleManager.h
+      ModuleSettings.cpp
+      ModuleSettings.h
+      NoteTrack.cpp
+      NoteTrack.h
+      NumberScale.h
+      PitchName.cpp
+      PitchName.h
+      PlatformCompatibility.cpp
+      PlatformCompatibility.h
+      PlaybackSchedule.cpp
+      PlaybackSchedule.h
+      PluginManager.cpp
+      PluginManager.h
+      PluginRegistrationDialog.cpp
+      PluginRegistrationDialog.h
+      Prefs.cpp
+      Prefs.h
+      Printing.cpp
+      Printing.h
+      Profiler.cpp
+      Profiler.h
+      Project.cpp
+      Project.h
+      ProjectAudioIO.cpp
+      ProjectAudioIO.h
+      ProjectAudioManager.cpp
+      ProjectAudioManager.h
+      ProjectFileIO.cpp
+      ProjectFileIO.h
+      ProjectFileIORegistry.cpp
+      ProjectFileIORegistry.h
+      ProjectFileManager.cpp
+      ProjectFileManager.h
+      ProjectHistory.cpp
+      ProjectHistory.h
+      ProjectManager.cpp
+      ProjectManager.h
+      ProjectSelectionManager.cpp
+      ProjectSelectionManager.h
+      ProjectSerializer.cpp
+      ProjectSerializer.h
+      ProjectSettings.cpp
+      ProjectSettings.h
+      ProjectStatus.cpp
+      ProjectStatus.h
+      ProjectWindow.cpp
+      ProjectWindow.h
+      ProjectWindowBase.cpp
+      ProjectWindowBase.h
+      RealFFTf.cpp
+      RealFFTf.h
+      RealFFTf48x.cpp
+      RealFFTf48x.h
+      RefreshCode.h
+      Registrar.h
+      Registry.cpp
+      Registry.h
+      Resample.cpp
+      Resample.h
+      RingBuffer.cpp
+      RingBuffer.h
+      SampleBlock.cpp
+      SampleBlock.h
+      SampleFormat.cpp
+      SampleFormat.h
+      Screenshot.cpp
+      Screenshot.h
+      SelectUtilities.cpp
+      SelectUtilities.h
+      SelectedRegion.cpp
+      SelectedRegion.h
+      SelectionState.cpp
+      SelectionState.h
+      Sequence.cpp
+      Sequence.h
+      Shuttle.cpp
+      Shuttle.h
+      ShuttleGetDefinition.cpp
+      ShuttleGetDefinition.h
+      ShuttleGui.cpp
+      ShuttleGui.h
+      ShuttlePrefs.cpp
+      ShuttlePrefs.h
+      Snap.cpp
+      Snap.h
+      SoundActivatedRecord.cpp
+      SoundActivatedRecord.h
+      Spectrum.cpp
+      Spectrum.h
+      SpectrumAnalyst.cpp
+      SpectrumAnalyst.h
+      SplashDialog.cpp
+      SplashDialog.h
+      SqliteSampleBlock.cpp
+      SseMathFuncs.cpp
+      SseMathFuncs.h
+      Tags.cpp
+      Tags.h
+      TempDirectory.cpp
+      TempDirectory.h
+      Theme.cpp
+      Theme.h
+      ThemeAsCeeCode.h
+      TimeDialog.cpp
+      TimeDialog.h
+      TimeTrack.cpp
+      TimeTrack.h
+      TimerRecordDialog.cpp
+      TimerRecordDialog.h
+      Track.cpp
+      Track.h
+      TrackArtist.cpp
+      TrackArtist.h
+      TrackInfo.cpp
+      TrackInfo.h
+      TrackPanel.cpp
+      TrackPanel.h
+      TrackPanelAx.cpp
+      TrackPanelAx.h
+      TrackPanelCell.cpp
+      TrackPanelCell.h
+      TrackPanelDrawable.cpp
+      TrackPanelDrawable.h
+      TrackPanelDrawingContext.h
+      TrackPanelListener.h
+      TrackPanelMouseEvent.h
+      TrackPanelResizeHandle.cpp
+      TrackPanelResizeHandle.h
+      TrackPanelResizerCell.cpp
+      TrackPanelResizerCell.h
+      TrackUtilities.cpp
+      TrackUtilities.h
+      UIHandle.cpp
+      UIHandle.h
+      UndoManager.cpp
+      UndoManager.h
+      UserException.cpp
+      UserException.h
+      ViewInfo.cpp
+      ViewInfo.h
+      VoiceKey.cpp
+      VoiceKey.h
+      WaveClip.cpp
+      WaveClip.h
+      WaveTrack.cpp
+      WaveTrack.h
+      WaveTrackLocation.h
+      WrappedType.cpp
+      WrappedType.h
+      ZoomInfo.cpp
+      ZoomInfo.h
+      float_cast.h
+      wxFileNameWrapper.h
+
+      # Commands
+
+      commands/AppCommandEvent.cpp
+      commands/AppCommandEvent.h
+      commands/AudacityCommand.cpp
+      commands/AudacityCommand.h
+      commands/BatchEvalCommand.cpp
+      commands/BatchEvalCommand.h
+      commands/Command.cpp
+      commands/Command.h
+      commands/CommandBuilder.cpp
+      commands/CommandBuilder.h
+      commands/CommandContext.cpp
+      commands/CommandContext.h
+      commands/CommandDirectory.cpp
+      commands/CommandDirectory.h
+      commands/CommandFlag.h
+      commands/CommandFunctors.h
+      commands/CommandHandler.cpp
+      commands/CommandHandler.h
+      commands/CommandManager.cpp
+      commands/CommandManager.h
+      commands/CommandManagerWindowClasses.h
+      commands/CommandMisc.h
+      commands/CommandSignature.cpp
+      commands/CommandSignature.h
+      commands/CommandTargets.cpp
+      commands/CommandTargets.h
+      commands/CommandType.cpp
+      commands/CommandType.h
+      commands/CompareAudioCommand.cpp
+      commands/CompareAudioCommand.h
+      commands/Demo.cpp
+      commands/Demo.h
+      commands/DragCommand.cpp
+      commands/DragCommand.h
+      commands/GetInfoCommand.cpp
+      commands/GetInfoCommand.h
+      commands/GetTrackInfoCommand.cpp
+      commands/GetTrackInfoCommand.h
+      commands/HelpCommand.cpp
+      commands/HelpCommand.h
+      commands/ImportExportCommands.cpp
+      commands/ImportExportCommands.h
+      commands/Keyboard.cpp
+      commands/Keyboard.h
+      commands/LoadCommands.cpp
+      commands/LoadCommands.h
+      commands/MessageCommand.cpp
+      commands/MessageCommand.h
+      commands/OpenSaveCommands.cpp
+      commands/OpenSaveCommands.h
+      commands/PreferenceCommands.cpp
+      commands/PreferenceCommands.h
+      commands/ResponseQueue.cpp
+      commands/ResponseQueue.h
+      commands/ScreenshotCommand.cpp
+      commands/ScreenshotCommand.h
+      commands/ScriptCommandRelay.cpp
+      commands/ScriptCommandRelay.h
+      commands/SelectCommand.cpp
+      commands/SelectCommand.h
+      commands/SetClipCommand.cpp
+      commands/SetClipCommand.h
+      commands/SetEnvelopeCommand.cpp
+      commands/SetEnvelopeCommand.h
+      commands/SetLabelCommand.cpp
+      commands/SetLabelCommand.h
+      commands/SetProjectCommand.cpp
+      commands/SetProjectCommand.h
+      commands/SetTrackInfoCommand.cpp
+      commands/SetTrackInfoCommand.h
+      commands/Validators.h
+
+      # Built-in Effects
+
+      effects/Amplify.cpp
+      effects/Amplify.h
+      effects/AutoDuck.cpp
+      effects/AutoDuck.h
+      effects/BassTreble.cpp
+      effects/BassTreble.h
+      effects/Biquad.cpp
+      effects/Biquad.h
+      effects/ChangePitch.cpp
+      effects/ChangePitch.h
+      effects/ChangeSpeed.cpp
+      effects/ChangeSpeed.h
+      effects/ChangeTempo.cpp
+      effects/ChangeTempo.h
+      effects/ClickRemoval.cpp
+      effects/ClickRemoval.h
+      effects/Compressor.cpp
+      effects/Compressor.h
+      effects/Contrast.cpp
+      effects/Contrast.h
+      effects/Distortion.cpp
+      effects/Distortion.h
+      effects/DtmfGen.cpp
+      effects/DtmfGen.h
+      effects/EBUR128.cpp
+      effects/EBUR128.h
+      effects/Echo.cpp
+      effects/Echo.h
+      effects/Effect.cpp
+      effects/Effect.h
+      effects/EffectManager.cpp
+      effects/EffectManager.h
+      effects/EffectUI.cpp
+      effects/EffectUI.h
+      effects/Equalization.cpp
+      effects/Equalization.h
+      effects/Equalization48x.cpp
+      effects/Equalization48x.h
+      effects/Fade.cpp
+      effects/Fade.h
+      effects/FindClipping.cpp
+      effects/FindClipping.h
+      effects/Generator.cpp
+      effects/Generator.h
+      effects/Invert.cpp
+      effects/Invert.h
+      effects/LoadEffects.cpp
+      effects/LoadEffects.h
+      effects/Loudness.cpp
+      effects/Loudness.h
+      effects/Noise.cpp
+      effects/Noise.h
+      effects/NoiseReduction.cpp
+      effects/NoiseReduction.h
+      effects/NoiseRemoval.cpp
+      effects/NoiseRemoval.h
+      effects/Normalize.cpp
+      effects/Normalize.h
+      effects/Paulstretch.cpp
+      effects/Paulstretch.h
+      effects/Phaser.cpp
+      effects/Phaser.h
+      effects/RealtimeEffectManager.cpp
+      effects/RealtimeEffectManager.h
+      effects/Repair.cpp
+      effects/Repair.h
+      effects/Repeat.cpp
+      effects/Repeat.h
+      effects/Reverb.cpp
+      effects/Reverb.h
+      effects/Reverb_libSoX.h
+      effects/Reverse.cpp
+      effects/Reverse.h
+      effects/SBSMSEffect.cpp
+      effects/SBSMSEffect.h
+      effects/ScienFilter.cpp
+      effects/ScienFilter.h
+      effects/ScoreAlignDialog.cpp
+      effects/ScoreAlignDialog.h
+      effects/Silence.cpp
+      effects/Silence.h
+      effects/SimpleMono.cpp
+      effects/SimpleMono.h
+      effects/SoundTouchEffect.cpp
+      effects/SoundTouchEffect.h
+      effects/StereoToMono.cpp
+      effects/StereoToMono.h
+      effects/TimeScale.cpp
+      effects/TimeScale.h
+      effects/TimeWarper.cpp
+      effects/TimeWarper.h
+      effects/ToneGen.cpp
+      effects/ToneGen.h
+      effects/TruncSilence.cpp
+      effects/TruncSilence.h
+      effects/TwoPassSimpleMono.cpp
+      effects/TwoPassSimpleMono.h
+      effects/Wahwah.cpp
+      effects/Wahwah.h
+
+      # VST Effects
+
+      $<$<BOOL:${USE_VST}>:
+         effects/VST/VSTControl.h
+         effects/VST/VSTEffect.cpp
+         effects/VST/VSTEffect.h
+         effects/VST/aeffectx.h
+      >
+
+      $<$<AND:$<BOOL:${USE_VST}>,$<BOOL:${wxIS_GTK}>>:
+         effects/VST/VSTControlGTK.cpp
+         effects/VST/VSTControlGTK.h
+      >
+
+      $<$<AND:$<BOOL:${USE_VST}>,$<BOOL:${wxIS_WIN}>>:
+         effects/VST/VSTControlMSW.cpp
+         effects/VST/VSTControlMSW.h
+      >
+
+      $<$<AND:$<BOOL:${USE_VST}>,$<BOOL:${wxIS_MAC}>>:
+         effects/VST/VSTControlOSX.h
+         effects/VST/VSTControlOSX.mm
+      >
+
+      # Audio Unit Effects
+
+      $<$<AND:$<BOOL:${USE_AUDIO_UNITS}>,$<BOOL:${wxIS_MAC}>>:
+         effects/audiounits/AUControl.h
+         effects/audiounits/AUControl.mm
+         effects/audiounits/AudioUnitEffect.cpp
+         effects/audiounits/AudioUnitEffect.h
+      >
+
+      # Ladspa Effects
+
+      $<$<BOOL:${USE_LADSPA}>:
+         effects/ladspa/LadspaEffect.cpp
+         effects/ladspa/LadspaEffect.h
+         effects/ladspa/ladspa.h
+      >
+
+      # LV2 Effects
+
+      $<$<BOOL:${USE_LV2}>:
+         effects/lv2/LV2Effect.cpp
+         effects/lv2/LV2Effect.h
+         effects/lv2/LoadLV2.cpp
+         effects/lv2/LoadLV2.h
+         effects/lv2/NativeWindow.h
+         effects/lv2/lv2_external_ui.h
+         effects/lv2/zix/common.h
+         effects/lv2/zix/ring.cpp
+         effects/lv2/zix/ring.h
+      >
+
+      # Nyquist Effects
+
+      $<$<BOOL:${USE_NYQUIST}>:
+         effects/nyquist/LoadNyquist.cpp
+         effects/nyquist/LoadNyquist.h
+         effects/nyquist/Nyquist.cpp
+         effects/nyquist/Nyquist.h
+      >
+
+      # VAMP Effects
+
+      $<$<BOOL:${USE_VAMP}>:
+         effects/vamp/LoadVamp.cpp
+         effects/vamp/LoadVamp.h
+         effects/vamp/VampEffect.cpp
+         effects/vamp/VampEffect.h
+      >
+
+      # Export
+
+      export/Export.cpp
+      export/Export.h
+
+      # Standard exporters
+      export/ExportCL.cpp
+      export/ExportMP3.cpp
+      export/ExportMP3.h
+      export/ExportMultiple.cpp
+      export/ExportMultiple.h
+      export/ExportPCM.cpp
+
+      # Optional exporters
+      $<$<BOOL:${USE_FFMPEG}>:
+         export/ExportFFmpeg.cpp
+         export/ExportFFmpegDialogs.cpp
+         export/ExportFFmpegDialogs.h
+      >
+
+      $<$<BOOL:${USE_LIBFLAC}>:
+         export/ExportFLAC.cpp
+      >
+
+      $<$<BOOL:${USE_LIBTWOLAME}>:
+         export/ExportMP2.cpp
+      >
+
+      $<$<AND:$<BOOL:${USE_LIBOGG}>,$<BOOL:${USE_LIBVORBIS}>>:
+         export/ExportOGG.cpp
+      >
+
+      # Import
+
+      import/FormatClassifier.cpp
+      import/FormatClassifier.h
+      import/Import.cpp
+      import/Import.h
+      import/ImportForwards.h
+      import/MultiFormatReader.cpp
+      import/MultiFormatReader.h
+      import/RawAudioGuess.cpp
+      import/RawAudioGuess.h
+      import/SpecPowerMeter.cpp
+      import/SpecPowerMeter.h
+
+      # Standard importers
+
+      import/ImportAUP.cpp
+      import/ImportLOF.cpp
+      import/ImportPCM.cpp
+      import/ImportPlugin.h
+      import/ImportPlugin.cpp
+      import/ImportRaw.cpp
+      import/ImportRaw.h
+
+      # Optional importers
+
+      $<$<BOOL:${USE_FFMPEG}>:
+         import/ImportFFmpeg.cpp
+      >
+
+      $<$<BOOL:${USE_LIBFLAC}>:
+         import/ImportFLAC.cpp
+      >
+
+      $<$<BOOL:${USE_GSTREAMER}>:
+         import/ImportGStreamer.cpp
+      >
+
+      $<$<BOOL:${USE_MIDI}>:
+         import/ImportMIDI.cpp
+         import/ImportMIDI.h
+      >
+
+      $<$<BOOL:${USE_LIBMAD}>:
+         import/ImportMP3.cpp
+      >
+
+      $<$<AND:$<BOOL:${USE_LIBOGG}>,$<BOOL:${USE_LIBVORBIS}>>:
+         import/ImportOGG.cpp
+      >
+
+      # Menus
+
+      menus/ClipMenus.cpp
+      menus/EditMenus.cpp
+      menus/ExtraMenus.cpp
+      menus/FileMenus.cpp
+      menus/HelpMenus.cpp
+      menus/LabelMenus.cpp
+      menus/NavigationMenus.cpp
+      menus/PluginMenus.cpp
+      menus/SelectMenus.cpp
+      menus/ToolbarMenus.cpp
+      menus/TrackMenus.cpp
+      menus/TransportMenus.cpp
+      menus/ViewMenus.cpp
+      menus/WindowMenus.cpp
+
+      # Preferences
+
+      prefs/BatchPrefs.cpp
+      prefs/BatchPrefs.h
+      prefs/DevicePrefs.cpp
+      prefs/DevicePrefs.h
+      prefs/DirectoriesPrefs.cpp
+      prefs/DirectoriesPrefs.h
+      prefs/EffectsPrefs.cpp
+      prefs/EffectsPrefs.h
+      prefs/ExtImportPrefs.cpp
+      prefs/ExtImportPrefs.h
+      prefs/GUIPrefs.cpp
+      prefs/GUIPrefs.h
+      prefs/GUISettings.h
+      prefs/ImportExportPrefs.cpp
+      prefs/ImportExportPrefs.h
+      prefs/KeyConfigPrefs.cpp
+      prefs/KeyConfigPrefs.h
+      prefs/LibraryPrefs.cpp
+      prefs/LibraryPrefs.h
+      prefs/MidiIOPrefs.cpp
+      prefs/MidiIOPrefs.h
+      prefs/ModulePrefs.cpp
+      prefs/ModulePrefs.h
+      prefs/MousePrefs.cpp
+      prefs/MousePrefs.h
+      prefs/PlaybackPrefs.cpp
+      prefs/PlaybackPrefs.h
+      prefs/PrefsDialog.cpp
+      prefs/PrefsDialog.h
+      prefs/PrefsPanel.cpp
+      prefs/PrefsPanel.h
+      prefs/QualityPrefs.cpp
+      prefs/QualityPrefs.h
+      prefs/QualitySettings.cpp
+      prefs/QualitySettings.h
+      prefs/RecordingPrefs.cpp
+      prefs/RecordingPrefs.h
+      prefs/SpectrogramSettings.cpp
+      prefs/SpectrogramSettings.h
+      prefs/SpectrumPrefs.cpp
+      prefs/SpectrumPrefs.h
+      prefs/ThemePrefs.cpp
+      prefs/ThemePrefs.h
+      prefs/TracksBehaviorsPrefs.cpp
+      prefs/TracksBehaviorsPrefs.h
+      prefs/TracksPrefs.cpp
+      prefs/TracksPrefs.h
+      prefs/WarningsPrefs.cpp
+      prefs/WarningsPrefs.h
+      prefs/WaveformPrefs.cpp
+      prefs/WaveformPrefs.h
+      prefs/WaveformSettings.cpp
+      prefs/WaveformSettings.h
+
+      # Toolbars
+
+      toolbars/ControlToolBar.cpp
+      toolbars/ControlToolBar.h
+      toolbars/DeviceToolBar.cpp
+      toolbars/DeviceToolBar.h
+      toolbars/EditToolBar.cpp
+      toolbars/EditToolBar.h
+      toolbars/MeterToolBar.cpp
+      toolbars/MeterToolBar.h
+      toolbars/ScrubbingToolBar.cpp
+      toolbars/ScrubbingToolBar.h
+      toolbars/SelectionBar.cpp
+      toolbars/SelectionBar.h
+      toolbars/SelectionBarListener.h
+      toolbars/SpectralSelectionBar.cpp
+      toolbars/SpectralSelectionBar.h
+      toolbars/SpectralSelectionBarListener.h
+      toolbars/TimeToolBar.cpp
+      toolbars/TimeToolBar.h
+      toolbars/ToolBar.cpp
+      toolbars/ToolBar.h
+      toolbars/ToolDock.cpp
+      toolbars/ToolDock.h
+      toolbars/ToolManager.cpp
+      toolbars/ToolManager.h
+      toolbars/ToolsToolBar.cpp
+      toolbars/ToolsToolBar.h
+      toolbars/TranscriptionToolBar.cpp
+      toolbars/TranscriptionToolBar.h
+
+      # Tracks
+
+      tracks/labeltrack/ui/LabelDefaultClickHandle.cpp
+      tracks/labeltrack/ui/LabelDefaultClickHandle.h
+      tracks/labeltrack/ui/LabelGlyphHandle.cpp
+      tracks/labeltrack/ui/LabelGlyphHandle.h
+      tracks/labeltrack/ui/LabelTextHandle.cpp
+      tracks/labeltrack/ui/LabelTextHandle.h
+      tracks/labeltrack/ui/LabelTrackControls.cpp
+      tracks/labeltrack/ui/LabelTrackControls.h
+      tracks/labeltrack/ui/LabelTrackShifter.cpp
+      tracks/labeltrack/ui/LabelTrackVRulerControls.cpp
+      tracks/labeltrack/ui/LabelTrackVRulerControls.h
+      tracks/labeltrack/ui/LabelTrackView.cpp
+      tracks/labeltrack/ui/LabelTrackView.h
+      tracks/playabletrack/notetrack/ui/NoteTrackAffordanceControls.h
+      tracks/playabletrack/notetrack/ui/NoteTrackAffordanceControls.cpp
+      tracks/playabletrack/notetrack/ui/NoteTrackButtonHandle.cpp
+      tracks/playabletrack/notetrack/ui/NoteTrackButtonHandle.h
+      tracks/playabletrack/notetrack/ui/NoteTrackControls.cpp
+      tracks/playabletrack/notetrack/ui/NoteTrackControls.h
+      tracks/playabletrack/notetrack/ui/NoteTrackShifter.cpp
+      tracks/playabletrack/notetrack/ui/NoteTrackSliderHandles.cpp
+      tracks/playabletrack/notetrack/ui/NoteTrackSliderHandles.h
+      tracks/playabletrack/notetrack/ui/NoteTrackVRulerControls.cpp
+      tracks/playabletrack/notetrack/ui/NoteTrackVRulerControls.h
+      tracks/playabletrack/notetrack/ui/NoteTrackVZoomHandle.cpp
+      tracks/playabletrack/notetrack/ui/NoteTrackVZoomHandle.h
+      tracks/playabletrack/notetrack/ui/NoteTrackView.cpp
+      tracks/playabletrack/notetrack/ui/NoteTrackView.h
+      tracks/playabletrack/notetrack/ui/StretchHandle.cpp
+      tracks/playabletrack/notetrack/ui/StretchHandle.h
+      tracks/playabletrack/ui/PlayableTrackButtonHandles.cpp
+      tracks/playabletrack/ui/PlayableTrackButtonHandles.h
+      tracks/playabletrack/ui/PlayableTrackControls.cpp
+      tracks/playabletrack/ui/PlayableTrackControls.h
+      tracks/playabletrack/wavetrack/ui/CutlineHandle.cpp
+      tracks/playabletrack/wavetrack/ui/CutlineHandle.h
+      tracks/playabletrack/wavetrack/ui/SampleHandle.cpp
+      tracks/playabletrack/wavetrack/ui/SampleHandle.h
+      tracks/playabletrack/wavetrack/ui/SpectrumVRulerControls.cpp
+      tracks/playabletrack/wavetrack/ui/SpectrumVRulerControls.h
+      tracks/playabletrack/wavetrack/ui/SpectrumVZoomHandle.cpp
+      tracks/playabletrack/wavetrack/ui/SpectrumVZoomHandle.h
+      tracks/playabletrack/wavetrack/ui/SpectrumView.cpp
+      tracks/playabletrack/wavetrack/ui/SpectrumView.h
+      tracks/playabletrack/wavetrack/ui/WaveTrackAffordanceControls.cpp
+      tracks/playabletrack/wavetrack/ui/WaveTrackAffordanceControls.h
+      tracks/playabletrack/wavetrack/ui/WaveTrackControls.cpp
+      tracks/playabletrack/wavetrack/ui/WaveTrackControls.h
+      tracks/playabletrack/wavetrack/ui/WaveTrackShifter.cpp
+      tracks/playabletrack/wavetrack/ui/WaveTrackSliderHandles.cpp
+      tracks/playabletrack/wavetrack/ui/WaveTrackSliderHandles.h
+      tracks/playabletrack/wavetrack/ui/WaveTrackVRulerControls.cpp
+      tracks/playabletrack/wavetrack/ui/WaveTrackVRulerControls.h
+      tracks/playabletrack/wavetrack/ui/WaveTrackVZoomHandle.cpp
+      tracks/playabletrack/wavetrack/ui/WaveTrackVZoomHandle.h
+      tracks/playabletrack/wavetrack/ui/WaveTrackView.cpp
+      tracks/playabletrack/wavetrack/ui/WaveTrackView.h
+      tracks/playabletrack/wavetrack/ui/WaveTrackViewConstants.cpp
+      tracks/playabletrack/wavetrack/ui/WaveTrackViewConstants.h
+      tracks/playabletrack/wavetrack/ui/WaveformVRulerControls.cpp
+      tracks/playabletrack/wavetrack/ui/WaveformVRulerControls.h
+      tracks/playabletrack/wavetrack/ui/WaveformVZoomHandle.cpp
+      tracks/playabletrack/wavetrack/ui/WaveformVZoomHandle.h
+      tracks/playabletrack/wavetrack/ui/WaveformView.cpp
+      tracks/playabletrack/wavetrack/ui/WaveformView.h
+      tracks/timetrack/ui/TimeTrackControls.cpp
+      tracks/timetrack/ui/TimeTrackControls.h
+      tracks/timetrack/ui/TimeTrackVRulerControls.cpp
+      tracks/timetrack/ui/TimeTrackVRulerControls.h
+      tracks/timetrack/ui/TimeTrackVZoomHandle.cpp
+      tracks/timetrack/ui/TimeTrackVZoomHandle.h
+      tracks/timetrack/ui/TimeTrackView.cpp
+      tracks/timetrack/ui/TimeTrackView.h
+
+      # Tracks UI
+
+      tracks/ui/AffordanceHandle.cpp
+      tracks/ui/AffordanceHandle.h
+      tracks/ui/BackgroundCell.cpp
+      tracks/ui/BackgroundCell.h
+      tracks/ui/ButtonHandle.cpp
+      tracks/ui/ButtonHandle.h
+      tracks/ui/CommonTrackControls.cpp
+      tracks/ui/CommonTrackControls.h
+      tracks/ui/CommonTrackPanelCell.cpp
+      tracks/ui/CommonTrackPanelCell.h
+      tracks/ui/CommonTrackView.cpp
+      tracks/ui/CommonTrackView.h
+      tracks/ui/EditCursorOverlay.cpp
+      tracks/ui/EditCursorOverlay.h
+      tracks/ui/EnvelopeHandle.cpp
+      tracks/ui/EnvelopeHandle.h
+      tracks/ui/PlayIndicatorOverlay.cpp
+      tracks/ui/PlayIndicatorOverlay.h
+      tracks/ui/ScrubUI.cpp
+      tracks/ui/ScrubUI.h
+      tracks/ui/Scrubbing.cpp
+      tracks/ui/Scrubbing.h
+      tracks/ui/SelectHandle.cpp
+      tracks/ui/SelectHandle.h
+      tracks/ui/SliderHandle.cpp
+      tracks/ui/SliderHandle.h
+      tracks/ui/TimeShiftHandle.cpp
+      tracks/ui/TimeShiftHandle.h
+      tracks/ui/TrackButtonHandles.cpp
+      tracks/ui/TrackButtonHandles.h
+      tracks/ui/TrackControls.cpp
+      tracks/ui/TrackControls.h
+      tracks/ui/TrackSelectHandle.cpp
+      tracks/ui/TrackSelectHandle.h
+      tracks/ui/TrackVRulerControls.cpp
+      tracks/ui/TrackVRulerControls.h
+      tracks/ui/TrackView.cpp
+      tracks/ui/TrackView.h
+      tracks/ui/ZoomHandle.cpp
+      tracks/ui/ZoomHandle.h
+
+      # ui helpers
+      ui/AccessibleLinksFormatter.h
+      ui/AccessibleLinksFormatter.cpp
+
+      # Widgets
+
+      widgets/AButton.cpp
+      widgets/AButton.h
+      widgets/ASlider.cpp
+      widgets/ASlider.h
+      widgets/AttachableScrollBar.cpp
+      widgets/AttachableScrollBar.h
+      widgets/AudacityMessageBox.cpp
+      widgets/AudacityMessageBox.h
+      widgets/BackedPanel.cpp
+      widgets/BackedPanel.h
+      widgets/ErrorDialog.cpp
+      widgets/ErrorDialog.h
+      widgets/ExpandingToolBar.cpp
+      widgets/ExpandingToolBar.h
+      widgets/FileConfig.cpp
+      widgets/FileConfig.h
+      widgets/FileDialog/FileDialog.cpp
+      widgets/FileDialog/FileDialog.h
+      $<$<BOOL:${wxIS_WIN}>:
+         widgets/FileDialog/win/FileDialogPrivate.cpp
+         widgets/FileDialog/win/FileDialogPrivate.h
+      >
+      $<$<BOOL:${wxIS_MAC}>:
+         widgets/FileDialog/mac/FileDialogPrivate.mm
+         widgets/FileDialog/mac/FileDialogPrivate.h
+      >
+      $<$<BOOL:${wxIS_GTK}>:
+         widgets/FileDialog/gtk/FileDialogPrivate.cpp
+         widgets/FileDialog/gtk/FileDialogPrivate.h
+      >
+      widgets/FileHistory.cpp
+      widgets/FileHistory.h
+      widgets/Grabber.cpp
+      widgets/Grabber.h
+      widgets/Grid.cpp
+      widgets/Grid.h
+      widgets/HelpSystem.cpp
+      widgets/HelpSystem.h
+      widgets/HtmlWindow.cpp
+      widgets/HtmlWindow.h
+      widgets/ImageRoll.cpp
+      widgets/ImageRoll.h
+      widgets/KeyView.cpp
+      widgets/KeyView.h
+      widgets/Meter.cpp
+      widgets/Meter.h
+      widgets/MeterPanelBase.cpp
+      widgets/MeterPanelBase.h
+      widgets/MultiDialog.cpp
+      widgets/MultiDialog.h
+      widgets/NumericTextCtrl.cpp
+      widgets/NumericTextCtrl.h
+      widgets/Overlay.cpp
+      widgets/Overlay.h
+      widgets/OverlayPanel.cpp
+      widgets/OverlayPanel.h
+      widgets/PopupMenuTable.cpp
+      widgets/PopupMenuTable.h
+      widgets/ProgressDialog.cpp
+      widgets/ProgressDialog.h
+      widgets/ReadOnlyText.h
+      widgets/Ruler.cpp
+      widgets/Ruler.h
+      widgets/UnwritableLocationErrorDialog.cpp
+      widgets/UnwritableLocationErrorDialog.h
+      widgets/Warning.cpp
+      widgets/Warning.h
+      widgets/WindowAccessible.cpp
+      widgets/WindowAccessible.h
+      widgets/numformatter.cpp
+      widgets/numformatter.h
+      widgets/valnum.cpp
+      widgets/valnum.h
+      widgets/wxPanelWrapper.cpp
+      widgets/wxPanelWrapper.h
+      widgets/wxTextCtrlWrapper.h
+      widgets/wxWidgetsBasicUI.cpp
+      widgets/wxWidgetsBasicUI.h
+
+      # XML handling
+      xml/XMLFileReader.cpp
+      xml/XMLFileReader.h
+      xml/XMLTagHandler.cpp
+      xml/XMLTagHandler.h
+      xml/XMLWriter.cpp
+      xml/XMLWriter.h
+      xml/audacityproject.dtd
+
+      Experimental.cmake
 )
 
 # ~~~
diff --git a/src/widgets/wxWidgetsBasicUI.cpp b/src/widgets/wxWidgetsBasicUI.cpp
new file mode 100644
index 000000000..dc2479dcf
--- /dev/null
+++ b/src/widgets/wxWidgetsBasicUI.cpp
@@ -0,0 +1,12 @@
+/*!********************************************************************
+
+Audacity: A Digital Audio Editor
+
+@file wxWidgetsBasicUI.cpp
+
+Paul Licameli
+
+**********************************************************************/
+#include "wxWidgetsBasicUI.h"
+
+wxWidgetsBasicUI::~wxWidgetsBasicUI() = default;
diff --git a/src/widgets/wxWidgetsBasicUI.h b/src/widgets/wxWidgetsBasicUI.h
new file mode 100644
index 000000000..d4077970a
--- /dev/null
+++ b/src/widgets/wxWidgetsBasicUI.h
@@ -0,0 +1,23 @@
+/*!********************************************************************
+
+Audacity: A Digital Audio Editor
+
+@file wxWidgetsBasicUI.h
+@brief Implementation of BasicUI using wxWidgets
+
+Paul Licameli
+
+**********************************************************************/
+#ifndef __WXWIDGETS_BASIC_UI__
+#define __WXWIDGETS_BASIC_UI__
+
+#include "BasicUI.h"
+
+//! An implementation of BasicUI::Services in terms of the wxWidgets toolkit
+/*! This is a singleton that doesn't need AUDACITY_DLL_API visibility */
+class wxWidgetsBasicUI final : public BasicUI::Services {
+public:
+   ~wxWidgetsBasicUI() override;
+};
+
+#endif