UndoManager Class Reference

Works with HistoryWindow to provide the Undo functionality. More...

#include <UndoManager.h>

Inheritance diagram for UndoManager:

Public Types
using	Consumer = std::function< void(const UndoState &) >

Public Member Functions
	UndoManager ()
	~UndoManager ()
	UndoManager (const UndoManager &)=delete
UndoManager &	operator= (const UndoManager &)=delete
void	PushState (const TrackList *l, const SelectedRegion &selectedRegion, const std::shared_ptr< Tags > &tags, const wxString &longDescription, const wxString &shortDescription, UndoPush flags=UndoPush::AUTOSAVE)
void	ModifyState (const TrackList *l, const SelectedRegion &selectedRegion, const std::shared_ptr< Tags > &tags)
void	ClearStates ()
void	RemoveStates (int num)
void	RemoveStateAt (int n)
unsigned int	GetNumStates ()
unsigned int	GetCurrentState ()
void	StopConsolidating ()
void	GetShortDescription (unsigned int n, wxString *desc)
wxLongLong_t	GetLongDescription (unsigned int n, wxString *desc, wxString *size)
void	SetLongDescription (unsigned int n, const wxString &desc)
void	SetStateTo (unsigned int n, const Consumer &consumer)
void	Undo (const Consumer &consumer)
void	Redo (const Consumer &consumer)
bool	UndoAvailable ()
bool	RedoAvailable ()
bool	UnsavedChanges ()
void	StateSaved ()
wxLongLong_t	GetClipboardSpaceUsage () const
void	CalculateSpaceUsage ()
void	SetODChangesFlag ()
	to mark as unsaved changes without changing the state/tracks. More...
bool	HasODChangesFlag ()
void	ResetODChangesFlag ()

Private Attributes
int	current
int	saved
UndoStack	stack
wxString	lastAction
bool	mayConsolidate { false }
SpaceArray	space
unsigned long long	mClipboardSpaceUsage {}
bool	mODChanges
ODLock	mODChangesMutex

Detailed Description

Works with HistoryWindow to provide the Undo functionality.

Definition at line 107 of file UndoManager.h.

Member Typedef Documentation

using UndoManager::Consumer = std::function< void( const UndoState & ) >

Definition at line 137 of file UndoManager.h.

Constructor & Destructor Documentation

UndoManager::UndoManager

(

)

Definition at line 66 of file UndoManager.cpp.

References current, ResetODChangesFlag(), and saved.

{
   current = -1;
   saved = -1;
   ResetODChangesFlag();
}

UndoManager::~UndoManager

(

)

Definition at line 73 of file UndoManager.cpp.

References ClearStates().

{
   ClearStates();
}

UndoManager::UndoManager ( const UndoManager &  )

delete

Member Function Documentation

void UndoManager::CalculateSpaceUsage

(

)

Definition at line 115 of file UndoManager.cpp.

References AudacityProject::GetClipboardTracks(), mClipboardSpaceUsage, space, and stack.

Referenced by HistoryWindow::DoUpdate().

{
   space.clear();
   space.resize(stack.size(), 0);

   Set seen;

   // After copies and pastes, a block file may be used in more than
   // one place in one undo history state, and it may be used in more than
   // one undo history state.  It might even be used in two states, but not
   // in another state that is between them -- as when you have state A,
   // then make a cut to get state B, but then paste it back into state C.

   // So be sure to count each block file once only, in the last undo item that
   // contains it.

   // Why the last and not the first? Because the user of the History dialog
   // may DELETE undo states, oldest first.  To reclaim disk space you must
   // DELETE all states containing the block file.  So the block file's
   // contribution to space usage should be counted only in that latest state.

   for (size_t nn = stack.size(); nn--;)
   {
      // Scan all tracks at current level
      auto tracks = stack[nn]->state.tracks.get();
      space[nn] = CalculateUsage(tracks, &seen);
   }

   mClipboardSpaceUsage = CalculateUsage
      (AudacityProject::GetClipboardTracks(), nullptr);

   //TIMER_STOP( space_calc );
}

void UndoManager::ClearStates

(

)

Definition at line 198 of file UndoManager.cpp.

References current, RemoveStates(), saved, and stack.

Referenced by AudacityProject::InitialState(), AudacityProject::OnCloseWindow(), AudacityProject::ResetProjectToEmpty(), and ~UndoManager().

{
   RemoveStates(stack.size());
   current = -1;
   saved = -1;
}

wxLongLong_t UndoManager::GetClipboardSpaceUsage ( ) const

inline

Definition at line 151 of file UndoManager.h.

Referenced by HistoryWindow::DoUpdate().

   { return mClipboardSpaceUsage; }

unsigned int UndoManager::GetCurrentState

(

)

Definition at line 210 of file UndoManager.cpp.

References current.

Referenced by HistoryWindow::DoUpdate().

{
   return current + 1;  // the array is 0 based, the abstraction is 1 based
}

wxLongLong_t UndoManager::GetLongDescription	(	unsigned int	n,
		wxString *	desc,
		wxString *	size
	)

Definition at line 149 of file UndoManager.cpp.

References Internat::FormatSize(), space, and stack.

Referenced by HistoryWindow::DoUpdate().

{
   n -= 1; // 1 based to zero based

   wxASSERT(n < stack.size());
   wxASSERT(space.size() == stack.size());

   *desc = stack[n]->description;

   *size = Internat::FormatSize(space[n]);

   return space[n];
}

unsigned int UndoManager::GetNumStates

(

)

Definition at line 205 of file UndoManager.cpp.

References stack.

Referenced by HistoryWindow::DoUpdate().

{
   return stack.size();
}

void UndoManager::GetShortDescription	(	unsigned int	n,
		wxString *	desc
	)

Definition at line 164 of file UndoManager.cpp.

References stack.

{
   n -= 1; // 1 based to zero based

   wxASSERT(n < stack.size());

   *desc = stack[n]->shortDescription;
}

bool UndoManager::HasODChangesFlag

(

)

Definition at line 403 of file UndoManager.cpp.

References mODChanges, and mODChangesMutex.

Referenced by UnsavedChanges().

{
   bool ret;
   mODChangesMutex.Lock();
   ret=mODChanges;
   mODChangesMutex.Unlock();
   return ret;
}

void UndoManager::ModifyState	(	const TrackList *	l,
		const SelectedRegion &	selectedRegion,
		const std::shared_ptr< Tags > &	tags
	)

Definition at line 225 of file UndoManager.cpp.

References TrackList::Create(), current, safenew, SonifyBeginModifyState, SonifyEndModifyState, and stack.

Referenced by AudacityProject::ModifyState(), and PushState().

{
   if (current == wxNOT_FOUND) {
      return;
   }

   SonifyBeginModifyState();
   // Delete current -- not necessary, but let's reclaim space early
   stack[current]->state.tracks.reset();

   // Duplicate
   auto tracksCopy = TrackList::Create();
   for (auto t : *l) {
      if ( t->GetId() == TrackId{} )
         // Don't copy a pending added track
         continue;
      tracksCopy->Add(t->Duplicate());
   }

   // Replace
   stack[current]->state.tracks = std::move(tracksCopy);
   stack[current]->state.tags = tags;

   stack[current]->state.selectedRegion = selectedRegion;
   SonifyEndModifyState();

   // wxWidgets will own the event object
   QueueEvent( safenew wxCommandEvent{ EVT_UNDO_MODIFIED } );
}

UndoManager& UndoManager::operator= ( const UndoManager &  )

delete

void UndoManager::PushState	(	const TrackList *	l,
		const SelectedRegion &	selectedRegion,
		const std::shared_ptr< Tags > &	tags,
		const wxString &	longDescription,
		const wxString &	shortDescription,
		UndoPush	flags = UndoPush::AUTOSAVE
	)

Definition at line 257 of file UndoManager.cpp.

References CONSOLIDATE, TrackList::Create(), current, lastAction, mayConsolidate, MINIMAL, ModifyState(), RemoveStateAt(), safenew, saved, and stack.

Referenced by AudacityProject::InitialState(), and AudacityProject::PushState().

{
   unsigned int i;

   if ( ((flags & UndoPush::CONSOLIDATE) != UndoPush::MINIMAL) &&
       lastAction == longDescription &&
       mayConsolidate ) {
      ModifyState(l, selectedRegion, tags);
      // MB: If the "saved" state was modified by ModifyState, reset
      //  it so that UnsavedChanges returns true.
      if (current == saved) {
         saved = -1;
      }
      return;
   }

   auto tracksCopy = TrackList::Create();
   for (auto t : *l) {
      if ( t->GetId() == TrackId{} )
         // Don't copy a pending added track
         continue;
      tracksCopy->Add(t->Duplicate());
   }

   mayConsolidate = true;

   i = current + 1;
   while (i < stack.size()) {
      RemoveStateAt(i);
   }

   // Assume tags was duplicted before any changes.
   // Just save a NEW shared_ptr to it.
   stack.push_back(
      std::make_unique<UndoStackElem>
         (std::move(tracksCopy),
            longDescription, shortDescription, selectedRegion, tags)
   );

   current++;

   if (saved >= current) {
      saved = -1;
   }

   lastAction = longDescription;

   // wxWidgets will own the event object
   QueueEvent( safenew wxCommandEvent{ EVT_UNDO_PUSHED } );
}

void UndoManager::Redo

(

const Consumer &

consumer

)

Definition at line 345 of file UndoManager.cpp.

References current, lastAction, mayConsolidate, RedoAvailable(), safenew, and stack.

{
   wxASSERT(RedoAvailable());

   current++;

   /*
   if (!RedoAvailable()) {
      *sel0 = stack[current]->sel0;
      *sel1 = stack[current]->sel1;
   }
   else {
      current++;
      *sel0 = stack[current]->sel0;
      *sel1 = stack[current]->sel1;
      current--;
   }
   */

   lastAction = wxT("");
   mayConsolidate = false;

   consumer( stack[current]->state );

   // wxWidgets will own the event object
   QueueEvent( safenew wxCommandEvent{ EVT_UNDO_RESET } );
}

bool UndoManager::RedoAvailable

(

)

Definition at line 220 of file UndoManager.cpp.

References current, and stack.

Referenced by Redo(), and AudacityProject::RedoAvailable().

{
   return (current < (int)stack.size() - 1);
}

void UndoManager::RemoveStateAt

(

int

n

)

Definition at line 182 of file UndoManager.cpp.

References stack.

Referenced by PushState(), and RemoveStates().

{
   stack.erase(stack.begin() + n);
}

void UndoManager::RemoveStates

(

int

num

)

Definition at line 188 of file UndoManager.cpp.

References current, RemoveStateAt(), and saved.

Referenced by ClearStates(), and HistoryWindow::OnDiscard().

{
   for (int i = 0; i < num; i++) {
      RemoveStateAt(0);

      current -= 1;
      saved -= 1;
   }
}

void UndoManager::ResetODChangesFlag

(

)

Definition at line 412 of file UndoManager.cpp.

References mODChanges, and mODChangesMutex.

Referenced by StateSaved(), and UndoManager().

{
   mODChangesMutex.Lock();
   mODChanges=false;
   mODChangesMutex.Unlock();
}

void UndoManager::SetLongDescription	(	unsigned int	n,
		const wxString &	desc
	)

Definition at line 173 of file UndoManager.cpp.

References desc, and stack.

{
   n -= 1;

   wxASSERT(n < stack.size());

   stack[n]->description = desc;
}

void UndoManager::SetODChangesFlag

(

)

to mark as unsaved changes without changing the state/tracks.

Definition at line 396 of file UndoManager.cpp.

References mODChanges, and mODChangesMutex.

{
   mODChangesMutex.Lock();
   mODChanges=true;
   mODChangesMutex.Unlock();
}

void UndoManager::SetStateTo	(	unsigned int	n,
		const Consumer &	consumer
	)

Definition at line 313 of file UndoManager.cpp.

References current, lastAction, mayConsolidate, safenew, and stack.

Referenced by AudacityProject::SetStateTo().

{
   n -= 1;

   wxASSERT(n < stack.size());

   current = n;

   lastAction = wxT("");
   mayConsolidate = false;

   consumer( stack[current]->state );

   // wxWidgets will own the event object
   QueueEvent( safenew wxCommandEvent{ EVT_UNDO_RESET } );
}

void UndoManager::StateSaved

(

)

Definition at line 378 of file UndoManager.cpp.

References current, ResetODChangesFlag(), and saved.

Referenced by AudacityProject::DoSave(), and AudacityProject::InitialState().

{
   saved = current;
   ResetODChangesFlag();
}

void UndoManager::StopConsolidating ( )

inline

Definition at line 128 of file UndoManager.h.

{ mayConsolidate = false; }

void UndoManager::Undo

(

const Consumer &

consumer

)

Definition at line 330 of file UndoManager.cpp.

References current, lastAction, mayConsolidate, safenew, stack, and UndoAvailable().

{
   wxASSERT(UndoAvailable());

   current--;

   lastAction = wxT("");
   mayConsolidate = false;

   consumer( stack[current]->state );

   // wxWidgets will own the event object
   QueueEvent( safenew wxCommandEvent{ EVT_UNDO_RESET } );
}

bool UndoManager::UndoAvailable

(

)

Definition at line 215 of file UndoManager.cpp.

References current.

Referenced by Undo(), and AudacityProject::UndoAvailable().

{
   return (current > 0);
}

bool UndoManager::UnsavedChanges

(

)

Definition at line 373 of file UndoManager.cpp.

References current, HasODChangesFlag(), and saved.

Referenced by AudacityProject::OnCloseWindow().

{
   return (saved != current) || HasODChangesFlag();
}

Member Data Documentation

int UndoManager::current

private

Definition at line 164 of file UndoManager.h.

Referenced by ClearStates(), GetCurrentState(), ModifyState(), PushState(), Redo(), RedoAvailable(), RemoveStates(), SetStateTo(), StateSaved(), Undo(), UndoAvailable(), UndoManager(), and UnsavedChanges().

wxString UndoManager::lastAction

private

Definition at line 168 of file UndoManager.h.

Referenced by PushState(), Redo(), SetStateTo(), and Undo().

bool UndoManager::mayConsolidate { false }

private

Definition at line 169 of file UndoManager.h.

Referenced by PushState(), Redo(), SetStateTo(), and Undo().

unsigned long long UndoManager::mClipboardSpaceUsage {}

private

Definition at line 172 of file UndoManager.h.

Referenced by CalculateSpaceUsage().

bool UndoManager::mODChanges

private

Definition at line 174 of file UndoManager.h.

Referenced by HasODChangesFlag(), ResetODChangesFlag(), and SetODChangesFlag().

ODLock UndoManager::mODChangesMutex

private

Definition at line 175 of file UndoManager.h.

Referenced by HasODChangesFlag(), ResetODChangesFlag(), and SetODChangesFlag().

int UndoManager::saved

private

Definition at line 165 of file UndoManager.h.

Referenced by ClearStates(), PushState(), RemoveStates(), StateSaved(), UndoManager(), and UnsavedChanges().

SpaceArray UndoManager::space

private

Definition at line 171 of file UndoManager.h.

Referenced by CalculateSpaceUsage(), and GetLongDescription().

UndoStack UndoManager::stack

private

Definition at line 166 of file UndoManager.h.

Referenced by CalculateSpaceUsage(), ClearStates(), GetLongDescription(), GetNumStates(), GetShortDescription(), ModifyState(), PushState(), Redo(), RedoAvailable(), RemoveStateAt(), SetLongDescription(), SetStateTo(), and Undo().

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The documentation for this class was generated from the following files:

• UndoManager.h
• UndoManager.cpp