x11 resizing windows

Portal · 06-30-2019, 04:06 AM

If one creates a window using

Code:

win=XCreateSimpleWindow(dpy,RootWindow(dpy,screen) ,50,50,800,500,10, BlackPixel(dpy,screen), WhitePixel(dpy,screen));

"win" can be moved/resized by default. However, if I do:

Code:

childwin=XCreateSimpleWindow(dpy,win,50,50,200,100,2, BlackPixel(dpy,screen), grey.pixel);

"childwin" cannot be moved/resized by default. Why is this?

GazL · 06-30-2019, 01:44 PM

The top level window(s) of applications are usually managed by the Window Manager which does the moving/resizing. Child windows are not. To allow for a child window to be moved/resized, your application will need to handle it itself.

Typically the program needs to listen for configure notify events on the main window and then respond to any resizing events reported by moving and resizing its child windows as appropriate for the new size of the top level window.

Most folks can't be bothered to deal with all the detail this requires and use toolkits such as Qt or GTK that do all this sort of boiler-plate stuff for them.

I like writing programs with libX11, but you typically end up with a couple of hundred lines of code before your program even does anything.

Portal · 07-01-2019, 02:33 AM

oh that makes sense...thanks! I was wondering how Qt layouts work....
I know xlib can be messy, but I really want to start making my own window managers. Do you know any good tutorials on writing window managers?

GazL · 07-01-2019, 03:33 AM

If you don't mind C++ this one seems reasonable, though it looks like the author never completed the full series of articles. Still, what's there is useful.

Personally, I'd rather see it done in pure C as I'm not really a fan of the whole OO thing.

Portal · 07-01-2019, 09:38 AM

The guy does have the full code on github though. I will probably finish whatever he doesn't cover by reading the source code...
Yeah I also prefer raw C... despite all the fancy features C++ provides.