On Thu, Apr 14, 2016 at 04:28:11PM +0800, Jonas Ådahl wrote: > Hi, > > This is the continuation of the previous patch series meaning to split up > xdg_surface into different per-role interfaces, while making it possible to > map > more types of surfaces. It enables using xdg_shell to create tooltips and > other > non-grabbing popups, as well as introduces a declarative system for enabling > clients to position its child surfaces (such as menus and popovers) within the > "work area" of the compositor. > > Regarding the new popup interface, it should make it possible to use popups > for > both grabbing popup chains such as menus with sub menus, as well as tooltips > and non-grabbing popups. The one-popup-chain rule still exists, but one can > now > have multiple popups on the same surface. For example it is possible to a > non-grabbing pop over surface, while still showing tooltips on the toplevel > surface. > > One currently unsolved stacking related issue is how to avoid newly created > popups being stacked above previous ones. For example a tooltip on a menu item > will stacked under a sub menu surface if the sub menu is created after the > tooltip. > > The new positioning API is meant to provide a declarative high level > description of how the compositor should try to position the child surface if > it would overflow outside of some compositor specific "work area" (in the > protocol referred to as "constrained"). With this it should be possible to > describe most if not all common menu positioning semantics out there, with the > possibility to adding more rules later. > > With the new API, a client will perform the following operations to map a menu > that is to be expanded right of and below some user interface element (such as > button), flips vertically to the other side of the button if doesn't fit > below, > and slides along the x-axis if it would end up outside of the left or right > screen edge: > > toplevel_xdg_surface = xdg_surface of the toplevel surface > button_rect = surface window geometry relative rectangle of the button widget > menu_window_rect = window geometry of the menu surface > > /* Create base interfaces. */ > menu_wl_surface = wl_compositor.create_surface() > menu_xdg_surface = xdg_shell.get_xdg_surface(menu_wl_surface) > > /* Set up positioning description. */ > menu_xdg_positioner = xdg_shell.create_positioner() > menu_xdg_positioner.set_anchor_rect(button_rect) > menu_xdg_positioner.set_gravity(gravity_bottom|gravity_right) > menu_xdg_positioner.set_anchor(anchor_bottom|anchor_right) > menu_xdg_positioner.set_constrain_action(slide_x|flip_y) > > /* Make it a popup. */ > menu_xdg_popup = xdg_surface.get_popup(menu_xdg_surface, > toplevel_xdg_surface, > menu_xdg_positioner) > menu_xdg_positioner.destroy() > > /* Set up initial required state. */ > menu_xdg_surface.set_window_geometry(menu_window_rect) > menu_xdg_popup.grab(seat, serial) > > /* Commit intial state (note now content is attached!). */ > menu_wl_surface.commit()
Obviously "now" here is a typo, and should be "no". *no* content is attached at this stage. (Thanks Pekka for pointing this out) Jonas > > ... compositor will given the window geometry and parent surface compute a > resulting position. .... > > *** received from the compositor: menu_xdg_popup.configure(x, y), > menu_xdg_surface.configure(serial) > > menu_wl_surface.attach(buffer_with_menu_content_drawn_into_it) > menu_wl_surface.commit() > > .. compositor will map the surface at the previously computer position > > The currently unsolved problems with the positioning API is whether it is > within scope to provide wl_subsurface like parent-child state synchronization > capabilities, whether a popup can ever be moved once it has been initially > positioned, and whether to allow the client to move the popup after it has > been > positioned (by setting new positioners). > > Moving could easily be added in a later revision, but parent-child state > synchronization and whether the compositor is allowed move the popup after it > was initially positioned are probably questions that should be answered up > front. > > > Jonas > > > > Jonas Ådahl (7): > xdg-shell: Turn xdg_surface into a generic base interface > xdg-shell: Put xdg_shell events after requests > xdg-shell: Add error codes for invalid surface state > xdg-shell: Improve error enum formatting some > xdg-shell: Make get_popup take a xdg_surface instead of wl_surface > xdg-shell: Make xdg_popup non-grabbing by default > xdg-shell: Introduce xdg_positioner > > unstable/xdg-shell/xdg-shell-unstable-v6.xml | 586 > ++++++++++++++++++++------- > 1 file changed, 437 insertions(+), 149 deletions(-) > > -- > 2.4.3 > _______________________________________________ wayland-devel mailing list wayland-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/wayland-devel
