I just switched to dkwm (https://bitbucket.org/natemaia/dk/src/master/), pretty good and light, it is really near bspwm. And I wanted to make my own bar to go with, I use this : https://github.com/fahmiirsyadk/ox. The bar is starting to look nice, but the problem is that the wm doesn't know there is a bar, so the windows are full screen (and go under the bar).

So my question is how does the wm know there is a bar and how to specfy the height ?

Thanks you