Bug144: Editing performance when Karaoke window is open and very many labels...

... in the first label track.

Problem was calling wxTextCtrl::AppendText once per label, per push of undo
stack, each call causing event handling.

Now call it only once per push.

src/Lyrics.cpp

@@ -18,6 +18,7 @@
 #include "Lyrics.h"
 #include "Internat.h"
 #include "Project.h" // for GetActiveProject
+#include "LabelTrack.h"
 
 #include <wx/arrimpl.cpp>
 WX_DEFINE_OBJARRAY(SyllableArray);
@@ -131,43 +132,59 @@ void Lyrics::Clear()
    mHighlightTextCtrl->Clear();
 }
 
-void Lyrics::Add(double t, wxString syllable)
+void Lyrics::AddLabels(const LabelTrack *pLT)
+{
+   const size_t numLabels = pLT->GetNumLabels();
+   wxString highlightText;
+   for (size_t ii = 0; ii < numLabels; ++ii) {
+      const LabelStruct *const pLabel = pLT->GetLabel(ii);
+      Add(pLabel->getT0(), pLabel->title, highlightText);
+   }
+   mHighlightTextCtrl->AppendText(highlightText);
+}
+
+void Lyrics::Add(double t, wxString syllable, wxString &highlightText)
 {
    int i = mSyllables.GetCount();
 
-   if (mSyllables[i-1].t == t) {
-      // We can't have two syllables with the same time, so append
-      // this to the end of the previous one if they're at the
-      // same time.
-      mSyllables[i-1].text += syllable;
-      mSyllables[i-1].textWithSpace += syllable;
-      mSyllables[i-1].char1 += syllable.Length();
-      return;
+   {
+      Syllable &prevSyllable = mSyllables[i - 1];
+
+      if (prevSyllable.t == t) {
+         // We can't have two syllables with the same time, so append
+         // this to the end of the previous one if they're at the
+         // same time.
+         prevSyllable.text += syllable;
+         prevSyllable.textWithSpace += syllable;
+         prevSyllable.char1 += syllable.Length();
+         return;
+      }
    }
 
    mSyllables.Add(Syllable());
-   mSyllables[i].t = t;
-   mSyllables[i].text = syllable;
+   Syllable &thisSyllable = mSyllables[i];
+   thisSyllable.t = t;
+   thisSyllable.text = syllable;
 
-   mSyllables[i].char0 = mText.Length();
+   thisSyllable.char0 = mText.Length();
 
    // Put a space between syllables unless the previous one
    // ended in a hyphen
    if (i > 0 &&
          // mSyllables[i-1].text.Length() > 0 &&
-         mSyllables[i-1].text.Right(1) != wxT("-"))
-      mSyllables[i].textWithSpace = wxT(" ") + syllable;
+         mSyllables[i - 1].text.Right(1) != wxT("-"))
+      thisSyllable.textWithSpace = wxT(" ") + syllable;
    else
-      mSyllables[i].textWithSpace = syllable;
+      thisSyllable.textWithSpace = syllable;
 
-   mText += mSyllables[i].textWithSpace;
-   mSyllables[i].char1 = mText.Length();
+   mText += thisSyllable.textWithSpace;
+   thisSyllable.char1 = mText.Length();
 
-   int nTextLen = mSyllables[i].textWithSpace.Length();
-   if ((nTextLen > 0) && (mSyllables[i].textWithSpace.Right(1) == wxT("_")))
-      mHighlightTextCtrl->AppendText(mSyllables[i].textWithSpace.Left(nTextLen - 1) + wxT("\n"));
+   int nTextLen = thisSyllable.textWithSpace.Length();
+   if ((nTextLen > 0) && (thisSyllable.textWithSpace.Right(1) == wxT("_")))
+      highlightText += (thisSyllable.textWithSpace.Left(nTextLen - 1) + wxT("\n"));
    else
-      mHighlightTextCtrl->AppendText(mSyllables[i].textWithSpace);
+      highlightText += thisSyllable.textWithSpace;
 }
 
 void Lyrics::Finish(double finalT)

src/Lyrics.h

@@ -18,6 +18,8 @@
 #include <wx/panel.h>
 #include <wx/textctrl.h>
 
+class LabelTrack;
+
 
 #define LYRICS_DEFAULT_WIDTH 608
 #define LYRICS_DEFAULT_HEIGHT 280
@@ -73,7 +75,7 @@ class Lyrics : public wxPanel
    virtual ~Lyrics();
 
    void Clear();
-   void Add(double t, wxString syllable);
+   void AddLabels(const LabelTrack *pLT);
    void Finish(double finalT);
 
    int FindSyllable(long startChar); // Find the syllable whose char0 <= startChar <= char1.
@@ -103,6 +105,8 @@ class Lyrics : public wxPanel
    void HandleLayout();
 
 private:
+   void Add(double t, wxString syllable, wxString &highlightText);
+
    unsigned int GetDefaultFontSize() const; // Depends on mLyricsStyle. Call only after mLyricsStyle is set.
 
    void SetDrawnFont(wxDC *dc); // for kBouncingBallLyrics

src/Project.cpp

@@ -4096,9 +4096,7 @@ void AudacityProject::UpdateLyrics()
 
    Lyrics* pLyricsPanel = mLyricsWindow->GetLyricsPanel();
    pLyricsPanel->Clear();
-   for (int i = 0; i < pLabelTrack->GetNumLabels(); i++)
-      pLyricsPanel->Add(pLabelTrack->GetLabel(i)->getT0(),
-                        pLabelTrack->GetLabel(i)->title);
+   pLyricsPanel->AddLabels(pLabelTrack);
    pLyricsPanel->Finish(pLabelTrack->GetEndTime());
    pLyricsPanel->Update(this->GetSel0());
 }