--- name: "wayland_xdg_positioner_t" section: "3" platform: "linux" package: "waylandpp-dev" version: "1.0.0-6+b2" release: "Debian 13 (Trixie)" platforms: ["linux"] url: "https://new.carta.tech/wayland_xdg_positioner_t" --- # wayland\_xdg\_positioner\_t(3) child surface positioner ## NAME wayland::xdg\_positioner\_t - child surface positioner ## SYNOPSIS `#include ` Inherits **wayland::proxy\_t**. ### Public Types enum class **wrapper\_type** { **standard**, **display**, **foreign**, **proxy\_wrapper** }\ ### Public Member Functions void **set\_size** (int32\_t width, int32\_t height)\ set the size of the to-be positioned rectangle void **set\_anchor\_rect** (int32\_t x, int32\_t y, int32\_t width, int32\_t height)\ set the anchor rectangle within the parent surface void **set\_anchor** (xdg\_positioner\_anchor const &anchor)\ set anchor rectangle anchor void **set\_gravity** (xdg\_positioner\_gravity const &gravity)\ set child surface gravity void **set\_constraint\_adjustment** (**xdg\_positioner\_constraint\_adjustment** const &constraint\_adjustment)\ set the adjustment to be done when constrained void **set\_offset** (int32\_t x, int32\_t y)\ set surface position offset void **set\_reactive** ()\ continuously reconstrain the surface bool **can\_set\_reactive** () const\ Check whether the **set\_reactive** function is available with the currently bound version of the protocol. void **set\_parent\_size** (int32\_t parent\_width, int32\_t parent\_height)\ bool **can\_set\_parent\_size** () const\ Check whether the **set\_parent\_size** function is available with the currently bound version of the protocol. void **set\_parent\_configure** (uint32\_t serial)\ set parent configure this is a response to bool **can\_set\_parent\_configure** () const\ Check whether the **set\_parent\_configure** function is available with the currently bound version of the protocol. uint32\_t **get\_id** () const\ Get the id of a proxy object. std::string **get\_class** () const\ Get the interface name (class) of a proxy object. uint32\_t **get\_version** () const\ Get the protocol object version of a proxy object. **wrapper\_type** **get\_wrapper\_type** () const\ Get the type of a proxy object. void **set\_queue** (**event\_queue\_t** queue)\ Assign a proxy to an event queue. wl\_proxy \* **c\_ptr** () const\ Get a pointer to the underlying C struct. bool **proxy\_has\_object** () const\ Check whether this wrapper actually wraps an object. **operator bool** () const\ Check whether this wrapper actually wraps an object. bool **operator==** (const **proxy\_t** &right) const\ Check whether two wrappers refer to the same object. bool **operator!=** (const **proxy\_t** &right) const\ Check whether two wrappers refer to different objects. void **proxy\_release** ()\ Release the wrapped object (if any), making this an empty wrapper. ### Static Public Attributes static constexpr std::uint32\_t **set\_size\_since\_version** = 1\ Minimum protocol version required for the **set\_size** function. static constexpr std::uint32\_t **set\_anchor\_rect\_since\_version** = 1\ Minimum protocol version required for the **set\_anchor\_rect** function. static constexpr std::uint32\_t **set\_anchor\_since\_version** = 1\ Minimum protocol version required for the **set\_anchor** function. static constexpr std::uint32\_t **set\_gravity\_since\_version** = 1\ Minimum protocol version required for the **set\_gravity** function. static constexpr std::uint32\_t **set\_constraint\_adjustment\_since\_version** = 1\ Minimum protocol version required for the **set\_constraint\_adjustment** function. static constexpr std::uint32\_t **set\_offset\_since\_version** = 1\ Minimum protocol version required for the **set\_offset** function. static constexpr std::uint32\_t **set\_reactive\_since\_version** = 3\ Minimum protocol version required for the **set\_reactive** function. static constexpr std::uint32\_t **set\_parent\_size\_since\_version** = 3\ Minimum protocol version required for the **set\_parent\_size** function. static constexpr std::uint32\_t **set\_parent\_configure\_since\_version** = 3\ Minimum protocol version required for the **set\_parent\_configure** function. ## Detailed Description child surface positioner The xdg\_positioner provides a collection of rules for the placement of a child surface relative to a parent surface. Rules can be defined to ensure the child surface remains within the visible area's borders, and to specify how the child surface changes its position, such as sliding along an axis, or flipping around a rectangle. These positioner-created rules are constrained by the requirement that a child surface must intersect with or be at least partially adjacent to its parent surface. See the various requests for details about possible rules. At the time of the request, the compositor makes a copy of the rules specified by the xdg\_positioner. Thus, after the request is complete the xdg\_positioner object can be destroyed or reused; further changes to the object will have no effect on previous usages. For an xdg\_positioner object to be considered complete, it must have a non-zero size set by set\_size, and a non-zero anchor rectangle set by set\_anchor\_rect. Passing an incomplete xdg\_positioner object when positioning a surface raises an error. Definition at line **669** of file **wayland-client-protocol-extra.hpp**. ## Member Enumeration Documentation ### enum class wayland::proxy\_t::wrapper\_type` [strong]`, ` [inherited]` Underlying wl\_proxy type and properties of a **proxy\_t** that affect construction, destruction, and event handling **Enumerator** - *standard* *C pointer is a standard type compatible with wl\_proxy\*. Events are dispatched and it is destructed when the* **proxy\_t** *is destructed. User data is set.* - *display* *C pointer is a wl\_display\*. No events are dispatched, wl\_display\_disconnect is called when the* **proxy\_t** *is destructed. User data is set.* - *foreign* *C pointer is a standard type compatible with wl\_proxy\*, but another library owns it and it should not be touched in a way that could affect the operation of the other library. No events are dispatched, wl\_proxy\_destroy is not called when the* **proxy\_t** *is destructed, user data is not touched. Consequently, there is no reference counting for the* **proxy\_t***. Lifetime of such wrappers should preferably be short to minimize the chance that the owning library decides to destroy the wl\_proxy.* - *proxy\_wrapper* *C pointer is a wl\_proxy\* that was constructed with wl\_proxy\_create\_wrapper. No events are dispatched, wl\_proxy\_wrapper\_destroy is called when the* **proxy\_t** *is destroyed. Reference counting is active. A reference to the* **proxy\_t** *creating this proxy wrapper is held to extend its lifetime until after the proxy wrapper is destroyed.* *Definition at line* **116** *of file* **wayland-client.hpp***.* ## Member Function Documentation ### wl\_proxy \* wayland::proxy\_t::c\_ptr () const` [inherited]` *Get a pointer to the underlying C struct.* **Returns** *The underlying wl\_proxy wrapped by this* **proxy\_t** *if it exists, otherwise an exception is thrown* ### bool xdg\_positioner\_t::can\_set\_parent\_configure () const *Check whether the* **set\_parent\_configure** *function is available with the currently bound version of the protocol.* *Definition at line* **1168** *of file* **wayland-client-protocol-extra.cpp***.* ### bool xdg\_positioner\_t::can\_set\_parent\_size () const *Check whether the* **set\_parent\_size** *function is available with the currently bound version of the protocol.* *Definition at line* **1157** *of file* **wayland-client-protocol-extra.cpp***.* ### bool xdg\_positioner\_t::can\_set\_reactive () const *Check whether the* **set\_reactive** *function is available with the currently bound version of the protocol.* *Definition at line* **1146** *of file* **wayland-client-protocol-extra.cpp***.* ### std::string wayland::proxy\_t::get\_class () const` [inherited]` *Get the interface name (class) of a proxy object.* **Returns** *The interface name of the object associated with the proxy* ### uint32\_t wayland::proxy\_t::get\_id () const` [inherited]` *Get the id of a proxy object.* **Returns** *The id the object associated with the proxy* ### uint32\_t wayland::proxy\_t::get\_version () const` [inherited]` *Get the protocol object version of a proxy object. Gets the protocol object version of a proxy object, or 0 if the proxy was created with unversioned API.* *A returned value of 0 means that no version information is available, so the caller must make safe assumptions about the object's real version.* **display\_t** *will always return version 0.* **Returns** *The protocol object version of the proxy or 0* ### wrapper\_type wayland::proxy\_t::get\_wrapper\_type () const` [inline]`, ` [inherited]` *Get the type of a proxy object.* *Definition at line* **302** *of file* **wayland-client.hpp***.* ### wayland::proxy\_t::operator bool () const` [inherited]` *Check whether this wrapper actually wraps an object.* **Returns** *true if there is an underlying object, false if this wrapper is empty* ### bool wayland::proxy\_t::operator!= (const proxy\_t & right) const` [inherited]` *Check whether two wrappers refer to different objects.* ### bool wayland::proxy\_t::operator== (const proxy\_t & right) const` [inherited]` *Check whether two wrappers refer to the same object.* ### bool wayland::proxy\_t::proxy\_has\_object () const` [inherited]` *Check whether this wrapper actually wraps an object.* **Returns** *true if there is an underlying object, false if this wrapper is empty* ### void wayland::proxy\_t::proxy\_release ()` [inherited]` *Release the wrapped object (if any), making this an empty wrapper. Note that* **display\_t** *instances cannot be released this way. Attempts to do so are ignored.* **Examples** **foreign\_display.cpp***.* ### void xdg\_positioner\_t::set\_anchor (xdg\_positioner\_anchor const & anchor) *set anchor rectangle anchor* **Parameters** *anchor anchor* *Defines the anchor point for the anchor rectangle. The specified anchor is used derive an anchor point that the child surface will be positioned relative to. If a corner anchor is set (e.g. 'top\_left' or 'bottom\_right'), the anchor point will be at the specified corner; otherwise, the derived anchor point will be centered on the specified edge, or in the center of the anchor rectangle if no edge is specified.* *Definition at line* **1117** *of file* **wayland-client-protocol-extra.cpp***.* ### void xdg\_positioner\_t::set\_anchor\_rect (int32\_t x, int32\_t y, int32\_t width, int32\_t height) *set the anchor rectangle within the parent surface* **Parameters** *x x position of anchor rectangle* \ *y y position of anchor rectangle* \ *width width of anchor rectangle* \ *height height of anchor rectangle* *Specify the anchor rectangle within the parent surface that the child surface will be placed relative to. The rectangle is relative to the window geometry as defined by xdg\_surface.set\_window\_geometry of the parent surface.* *When the xdg\_positioner object is used to position a child surface, the anchor rectangle may not extend outside the window geometry of the positioned child's parent surface.* *If a negative size is set the invalid\_input error is raised.* *Definition at line* **1111** *of file* **wayland-client-protocol-extra.cpp***.* ### void xdg\_positioner\_t::set\_constraint\_adjustment (xdg\_positioner\_constraint\_adjustment const & constraint\_adjustment) *set the adjustment to be done when constrained* **Parameters** *constraint\_adjustment bit mask of constraint adjustments* *Specify how the window should be positioned if the originally intended position caused the surface to be constrained, meaning at least partially outside positioning boundaries set by the compositor. The adjustment is set by constructing a bitmask describing the adjustment to be made when the surface is constrained on that axis.* *If no bit for one axis is set, the compositor will assume that the child surface should not change its position on that axis when constrained.* *If more than one bit for one axis is set, the order of how adjustments are applied is specified in the corresponding adjustment descriptions.* *The default adjustment is none.* *Definition at line* **1129** *of file* **wayland-client-protocol-extra.cpp***.* ### void xdg\_positioner\_t::set\_gravity (xdg\_positioner\_gravity const & gravity) *set child surface gravity* **Parameters** *gravity gravity direction* *Defines in what direction a surface should be positioned, relative to the anchor point of the parent surface. If a corner gravity is specified (e.g. 'bottom\_right' or 'top\_left'), then the child surface will be placed towards the specified gravity; otherwise, the child surface will be centered over the anchor point on any axis that had no gravity specified.* *Definition at line* **1123** *of file* **wayland-client-protocol-extra.cpp***.* ### void xdg\_positioner\_t::set\_offset (int32\_t x, int32\_t y) *set surface position offset* **Parameters** *x surface position x offset* \ *y surface position y offset* *Specify the surface position offset relative to the position of the anchor on the anchor rectangle and the anchor on the surface. For example if the anchor of the anchor rectangle is at (x, y), the surface has the gravity bottom\|right, and the offset is (ox, oy), the calculated surface position will be (x + ox, y + oy). The offset position of the surface is the one used for constraint testing. See set\_constraint\_adjustment.* *An example use case is placing a popup menu on top of a user interface element, while aligning the user interface element of the parent surface with some user interface element placed somewhere in the popup surface.* *Definition at line* **1135** *of file* **wayland-client-protocol-extra.cpp***.* ### void xdg\_positioner\_t::set\_parent\_configure (uint32\_t serial) *set parent configure this is a response to* **Parameters** *serial serial of parent configure event* *Set the serial of an xdg\_surface.configure event this positioner will be used in response to. The compositor may use this information together with set\_parent\_size to determine what future state the popup should be constrained using.* *Definition at line* **1163** *of file* **wayland-client-protocol-extra.cpp***.* ### void xdg\_positioner\_t::set\_parent\_size (int32\_t parent\_width, int32\_t parent\_height) **Parameters** *parent\_width future window geometry width of parent* \ *parent\_height future window geometry height of parent* *Set the parent window geometry the compositor should use when positioning the popup. The compositor may use this information to determine the future state the popup should be constrained using. If this doesn't match the dimension of the parent the popup is eventually positioned against, the behavior is undefined.* *The arguments are given in the surface-local coordinate space.* *Definition at line* **1152** *of file* **wayland-client-protocol-extra.cpp***.* ### void wayland::proxy\_t::set\_queue (event\_queue\_t queue)` [inherited]` *Assign a proxy to an event queue.* **Parameters** *queue The event queue that will handle this proxy* *Assign proxy to event queue. Events coming from proxy will be queued in queue instead of the display's main queue.* *See also:* **display\_t::dispatch\_queue()***.* **Examples** **proxy\_wrapper.cpp***.* ### void xdg\_positioner\_t::set\_reactive () *continuously reconstrain the surface When set reactive, the surface is reconstrained if the conditions used for constraining changed, e.g. the parent window moved.* *If the conditions changed and the popup was reconstrained, an xdg\_popup.configure event is sent with updated geometry, followed by an xdg\_surface.configure event.* *Definition at line* **1141** *of file* **wayland-client-protocol-extra.cpp***.* ### void xdg\_positioner\_t::set\_size (int32\_t width, int32\_t height) *set the size of the to-be positioned rectangle* **Parameters** *width width of positioned rectangle* \ *height height of positioned rectangle* *Set the size of the surface that is to be positioned with the positioner object. The size is in surface-local coordinates and corresponds to the window geometry. See xdg\_surface.set\_window\_geometry.* *If a zero or negative size is set the invalid\_input error is raised.* *Definition at line* **1105** *of file* **wayland-client-protocol-extra.cpp***.* ## Member Data Documentation ### constexpr std::uint32\_t wayland::xdg\_positioner\_t::set\_anchor\_rect\_since\_version = 1` [static]`, ` [constexpr]` *Minimum protocol version required for the* **set\_anchor\_rect** *function.* *Definition at line* **730** *of file* **wayland-client-protocol-extra.hpp***.* ### constexpr std::uint32\_t wayland::xdg\_positioner\_t::set\_anchor\_since\_version = 1` [static]`, ` [constexpr]` *Minimum protocol version required for the* **set\_anchor** *function.* *Definition at line* **747** *of file* **wayland-client-protocol-extra.hpp***.* ### constexpr std::uint32\_t wayland::xdg\_positioner\_t::set\_constraint\_adjustment\_since\_version = 1` [static]`, ` [constexpr]` *Minimum protocol version required for the* **set\_constraint\_adjustment** *function.* *Definition at line* **788** *of file* **wayland-client-protocol-extra.hpp***.* ### constexpr std::uint32\_t wayland::xdg\_positioner\_t::set\_gravity\_since\_version = 1` [static]`, ` [constexpr]` *Minimum protocol version required for the* **set\_gravity** *function.* *Definition at line* **764** *of file* **wayland-client-protocol-extra.hpp***.* ### constexpr std::uint32\_t wayland::xdg\_positioner\_t::set\_offset\_since\_version = 1` [static]`, ` [constexpr]` *Minimum protocol version required for the* **set\_offset** *function.* *Definition at line* **811** *of file* **wayland-client-protocol-extra.hpp***.* ### constexpr std::uint32\_t wayland::xdg\_positioner\_t::set\_parent\_configure\_since\_version = 3` [static]`, ` [constexpr]` *Minimum protocol version required for the* **set\_parent\_configure** *function.* *Definition at line* **871** *of file* **wayland-client-protocol-extra.hpp***.* ### constexpr std::uint32\_t wayland::xdg\_positioner\_t::set\_parent\_size\_since\_version = 3` [static]`, ` [constexpr]` *Minimum protocol version required for the* **set\_parent\_size** *function.* *Definition at line* **851** *of file* **wayland-client-protocol-extra.hpp***.* ### constexpr std::uint32\_t wayland::xdg\_positioner\_t::set\_reactive\_since\_version = 3` [static]`, ` [constexpr]` *Minimum protocol version required for the* **set\_reactive** *function.* *Definition at line* **827** *of file* **wayland-client-protocol-extra.hpp***.* ### constexpr std::uint32\_t wayland::xdg\_positioner\_t::set\_size\_since\_version = 1` [static]`, ` [constexpr]` *Minimum protocol version required for the* **set\_size** *function.* *Definition at line* **706** *of file* **wayland-client-protocol-extra.hpp***.* ## Author *Generated automatically by Doxygen for Wayland++ from the source code.*