How to call Window.print() on a popup window in NWJS?

Question

In NWJS, I would like to open a popup window with a local file URL to a PDF and then print the PDF right away (on Windows). I tried doing this:

nw.Window.open(
  'file://' + downloadItem.filename.replace(/\\/g, '/'),
  {new_instance: true, height: 600, width: 800},
  function(pdfWin) {
    pdfWin.on('loaded', function() {
      this.print({autoprint: false});
    });
  }
);

But in the developer tools, it says that pdfWin is undefined, which is completely weird to me considering that it should work according to the documentation. I then tried using Window.open with nw.Window.get() and then but I get an error saying Blocked a frame with origin "chrome-extension://..." from accessing a cross-origin frame.

Any ideas?

Answer 1

Alright, I found the problem. The code above works if you take out new_instance: true. If that variable is marked as true, then this is undefined initially and the code doesn't work.