Problem with understanding the PhotoView class posted by Thomas Wieczorek @ Sat, 12 Jan 2008 10:46:08 -0000

Thomas Wieczorek — Sat, 12 Jan 2008 10:46:08 -0000

It’s a great book and I like how you go through the iterations.

IMHO it is more readable, when I add self to attributes which belong to the current class. I learned the hard way in Java that it is not much more to write to add this, but it keeps the code clearer for later reviews.

Problem with understanding the PhotoView class posted by Lyle Johnson @ Fri, 11 Jan 2008 22:38:16 -0000

Lyle Johnson — Fri, 11 Jan 2008 22:38:16 -0000

Thomas, you are a fast reader! Glad you figured it out on your own, but I’ll make a note to myself that that could be clearer in the book’s discussion of the code.

Problem with understanding the PhotoView class posted by Thomas Wieczorek @ Fri, 11 Jan 2008 18:09:59 -0000

Thomas Wieczorek — Fri, 11 Jan 2008 18:09:59 -0000

All right, I get it!
app is an instance variable of the superclass. You could also write self.app instead.

Sorry for the ruckus

Problem with understanding the PhotoView class posted by Thomas Wieczorek @ Fri, 11 Jan 2008 17:49:47 -0000

Thomas Wieczorek — Fri, 11 Jan 2008 17:49:47 -0000

I finished the third chapter and I am right now starting the fourth, but I don’t get one thing. Where does the PhotoView class gets its knowlegde of the app instance(page 33, pdf)?
Here’s the code:

class PhotoView < FXImageFrame

    def initialize(p, photo)
        super(p, nil)
        load_image(photo.path)
    end

    def load_image(path)    
        File.open(path, "rb") do |file|
            # I don't get it why "app" works!
            self.image = FXJPGImage.new(app, file.read)
        end
    end
end

app is only defined in the PictureBook class. How come that it works?

Recent Posts in 'Problem with understanding the PhotoView class' | Pragmatic Forums

Problem with understanding the PhotoView class posted by Thomas Wieczorek @ Sat, 12 Jan 2008 10:46:08 -0000

Problem with understanding the PhotoView class posted by Lyle Johnson @ Fri, 11 Jan 2008 22:38:16 -0000

Problem with understanding the PhotoView class posted by Thomas Wieczorek @ Fri, 11 Jan 2008 18:09:59 -0000

Problem with understanding the PhotoView class posted by Thomas Wieczorek @ Fri, 11 Jan 2008 17:49:47 -0000