Contradiction with show() method

Posted by David Webster on Mar 29, 2009; 8:34pm
URL: http://imagej.273.s1.nabble.com/Contradiction-with-show-method-tp3693120.html

I am learning Java via th "monkey see, monkey do" method and get what seems
to be a contradiction.

I ran a test similar to the one shown in Burger and Berge on page 502.(see
run method below). Without the updateAndDraw(),  the invert()
result should not be display'ed. But,
In case 1, with  the wait(2000) and updateAndDraw() commented out,
I  get the inverted image being displayed (It shouldn't be).
In case 2, I use the wait(200) and get only the original image being
displayed.
In case 3, I add the updateAndDraw() and get  the inverted image.
Only case 3 makes any sense


        public void run(ImageProcessor ip) {

                ImageProcessor ip1 = ip.duplicate();
                ImagePlus  im1 = new ImagePlus("im1",ip1);
                im1.show();
                //IJ.wait(2000);
                ip1.invert();
                //im1.updateAndDraw();
        }

David Webster