Problems with removing empty trailing bars

• May 15, 2021 - 16:06

Hi,

here is a German melody with some chords. Its construction is in this link for all people who can speak German.
https://youtu.be/3sqhHhwYTDI
This very composition ends with an empty bar with chords before it repeats and plays till "Fine". Unfortunately after that empty bar, there are some more empty bars with no chords.
If we go to Tools > Delete empty traling bars, then every empty traling bar will be deleted, even that one with the chords.
I think this bug should be fixed as some songs end with such bars and it is veery tedious to delete bars at the end.

Attachment	Size
After Removing Empty Trailing Bars.png	196.64 KB
Before Removing Empty Trailing Bars.png	34.56 KB
German song with such property.png	5.44 KB

Comments

Jojo-Schmitz

• May 15, 2021 - 16:12

Please report this in the issue tracker
The workaround is easy though, just select those measures and press Ctrl+Del

Here's the code responsible for this:

//---------------------------------------------------------
//   firstTrailingMeasure
//---------------------------------------------------------
 
Measure* Score::firstTrailingMeasure(ChordRest** cr)
      {
      Measure* firstMeasure = nullptr;
      auto m = lastMeasure();
 
      // No active selection: prepare first empty trailing measure of entire score
      if (!cr)
            for (; m && m->isFullMeasureRest(); firstMeasure = m, m = m->prevMeasure());
      // Active selection: select full measure rest of active staff's empty trailing measure
      else {
            ChordRest* tempCR = *cr;
            while (m && (tempCR = m->first()->nextChordRest(trackZeroVoice((*cr)->track()), false))->isFullMeasureRest()) {
                  *cr = tempCR;
                  firstMeasure = m;
                  m = m->prevMeasure();
                  }
            }
      return firstMeasure;
      }

Which reveals that it indeed, starting with the last measure, picks on measures with full measure rests, not checking for chord symbols or anything else that would e.g. prevent a staff from getting hidden.
Seems that using the same algorithm that does hide empty staves should get used here.

Another workaround: in that last measure with 2 chord symbols, use 2 rests, or more exact: not a full measure rest.

Jojo-Schmitz

• May 15, 2021 - 17:46

Changing

      if (!cr)
            for (; m && m->isFullMeasureRest(); firstMeasure = m, m = m->prevMeasure());

      if (!cr)
            for (; m && m->isEmpty(-1); firstMeasure = m, m = m->prevMeasure());

might work, if also fixing a bug in Measure::isEmpty() that makes it crash on the -1, regardless this being documented to work and to check all staves for being empty.
For the else branch a different approach might be needed though.

Jojo-Schmitz

• May 15, 2021 - 19:05

Thanks for #321227: Problems with removing empty trailing bars

bobjp

• May 15, 2021 - 20:19

Or until it gets fixed, put a whole note in that DC measure, and delete it after the four measures are deleted