Display on/off quirks

[K.Daube]

Dear experts

(FM-13.0.5.547) I have discovered a strange behaviour:
In the following order the location is not restored after the actions. It seems that SetDisplay destroys it:

  SetDisplay (false);
  savedTR = goCurrentDoc.TextSelection;
// Do a lot of things (loop) on various places in the document
  RestoreTR (goCurrentDoc, savedTR);
  SetDisplay (true);

In the following order things work as expected. Cursor location is restored.

  savedTR = goCurrentDoc.TextSelection;
  SetDisplay (false);
// Do a lot of things (loop) on various places in the document
  SetDisplay (true);
  RestoreTR (goCurrentDoc, savedTR);

The two functions are

function RestoreTR (oTargetDoc, oSavedTR) {
// actions may have left us on a reference page
var bodyPage = oTargetDoc.FirstBodyPageInDoc;  
  oTargetDoc.CurrentPage = bodyPage;  
  oTargetDoc.TextSelection = oSavedTR;  
  oTargetDoc.ScrollToText(oSavedTR);  
} //--- end RestoreTR 
function SetDisplay (bWanted) {
  if (bWanted) {                // switch ON
    if (app.Displaying === 0) {
      app.Displaying = 1;
    }
  } else {                      // switch OFF
    if (app.Displaying === 1) {
      app.Displaying = 0;
    }
  }
} //--- end SetDisplay

What may be the cause of this?

[frameexpert · Accepted solution]

Hi Klaus, I am not sure why this doesn't always work, but it may be that you don't always have a valid TextSelection when the script starts. Also, when you restore, you are assuming that you started on a body page. It may be better to have a "save" function that will be more specific about where you start. For example:

function saveCurrentLocation (doc) {
    var location = {};
    location.pgf = doc.TextSelection.beg.obj;
    location.offset = doc.TextSelection.beg.offset;
    location.page = doc.CurrentPage;
    return location;
}

Now your restore function may be more reliable:

function restoreLocation (doc, location) {
    var textRange, pgf;
    doc.CurrentPage = location.page;
    pgf = location.pgf;
    if (pgf.ObjectValid () === 1) {
        textRange = new TextRange (new TextLoc (pgf, location.offset),
            new TextLoc (pgf, location.offset));
        doc.TextSelection = textRange;
    }
}

[K.Daube]

Thank you, Rick

Your ideas always make the functions more universal!

The only missing thing was

  doc.ScrollToText(textRange);  

before leaving restoreLocation

Klaus