[Doitsu]

Originally Posted by fbrzvnrnd

This because some ebook readers (Lekt on Android and Azardi) give error when meet navigator.epubReadingSystem.name and stop the jevascript code.

I only have rudimentary JavaScript skills but checking navigator.hasOwnProperty should allow you to find out whether an epub3 app supports epubReadingSystem. (Apps that don't support epubReadingSystem usually only have minimal epub3 support.)

For a ready-made example, see this very simple epub3 test file, which uses the following code:

  function showinfo() {
      if (navigator && navigator.hasOwnProperty('epubReadingSystem')) {
          var versionInfo = "name: " + navigator.epubReadingSystem.name + " " + navigator.epubReadingSystem.version + "\nplatform: " + navigator.platform + "\nlayoutStyle: " + navigator.epubReadingSystem.layoutStyle + "\n";
          var features = ["dom-manipulation", "layout-changes", "touch-events", "mouse-events", "keyboard-events", "spine-scripting"];
          var featureLog = "";
          for (var i = 0; i < 6; i++) {
              if (navigator.epubReadingSystem.hasFeature(features[i])) {
                  featureLog += features[i] + ": supported\n";
              } else {
                  featureLog += features[i] + ": NOT supported\n";
              }
          }
          alert(versionInfo + featureLog);
      } else {
          alert('epubReadingSystem object not found.' + "\nappName: " + navigator.appName + "\nappVersion: " + navigator.appVersion + "\nplatform: " + navigator.platform);
      }
  }

It'll return Netscape as the navigator.appName value for Sigil, Azardi and Lektz. IMHO, Gitden Reader is usually better at rendering epub3 books than Lektz.