title: Absolute position of Flutter widgets
body: <p>I need to code an image viewer for images too large to fit on the screen. I want to adjust the position of the image so that I can control which section of the image is visible. My plan was to set the position with a negative value to move it outside the screen area but I can't seem to get that to work. Negative margins don't cut it either. Any other bright ideas?
  Thanks.</p>