> > On 8/18/2020 12:31 PM, James Platt wrote: >> I'm looking at implementing a zoom contents (not zoom window) feature in a >> GUI with lots of elements and I'm wondering about the best way to do this. >> Most, if not all, standard GUI widgets in Racket can be resized by changing >> the font size of their contents or label. Then redraw the widget and you >> have the whole thing in a new size. So zoom could be done by creating a >> function which handles each element individually but I would like a more >> general solution, if possible. Most widgets use the value >> normal-control-font for their default but it doesn't look like this can be >> changed at present. If there were a setter for normal-control-font, it >> looks like you could have a menu item change it, then recursively get the >> children of the frame it is attached to and redraw them. Would this >> actually work? Is there a better way to do it? > > If you can access (or render) the contents as a 'pict', then it be scaled > somewhat arbitrarily (though a scaled version is not guaranteed to look good). > https://docs.racket-lang.org/pict/Pict_Drawing_Adjusters.html > > It is a form of BitBLT operation. I would search the docs for "blt" or > "blit" in addition to "scale" and "size". Sorry I can't point you more > directly to relevant functions: I've done a lot of GUI programming, but, > unfortunately, I know it from C++ using device contexts directly, not from > using Racket's graphics.
If I understand correctly, I would do that like in the Stackoverflow post below. Note the need for using the bitmap% version of the button label. The advantage of this approach is that you can change the label dynamically with a send. The drawback is that I would have to create a modified version of every widget. I was just hoping for a solution which would not require so much customization of a standard Racket package. https://stackoverflow.com/questions/48414363/how-to-change-the-color-of-text-in-a-racket-gui-button/48468797#48468797 -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/racket-users/08CD0FAF-AFCD-4B43-87C4-422C79AA2361%40biomantica.com.
