offer to transfer data More...

#include <wayland-client-protocol.hpp>

Inheritance diagram for wayland::data_offer_t:

Collaboration diagram for wayland::data_offer_t:

Public Types
enum	wrapper_type { wrapper_type::standard, wrapper_type::display, wrapper_type::foreign, wrapper_type::proxy_wrapper }

Public Member Functions
void	accept (uint32_t serial, std::string mime_type)
	accept one of the offered mime types More...

void	receive (std::string mime_type, int fd)
	request that the data is transferred More...

void	finish ()
	the offer will no longer be used More...

bool	can_finish () const
	Check whether the finish function is available with the currently bound version of the protocol. More...

void	set_actions (data_device_manager_dnd_action dnd_actions, data_device_manager_dnd_action preferred_action)
	set the available/preferred drag-and-drop actions More...

bool	can_set_actions () const
	Check whether the set_actions function is available with the currently bound version of the protocol. More...

std::function< void(std::string)> &	on_offer ()
	advertise offered mime type More...

std::function< void(data_device_manager_dnd_action)> &	on_source_actions ()
	notify the source-side available actions More...

std::function< void(data_device_manager_dnd_action)> &	on_action ()
	notify the selected action More...

uint32_t	get_id () const
	Get the id of a proxy object. More...

std::string	get_class () const
	Get the interface name (class) of a proxy object. More...

uint32_t	get_version () const
	Get the protocol object version of a proxy object. More...

wrapper_type	get_wrapper_type () const
	Get the type of a proxy object. More...

void	set_queue (event_queue_t queue)
	Assign a proxy to an event queue. More...

wl_proxy *	c_ptr () const
	Get a pointer to the underlying C struct. More...

bool	proxy_has_object () const
	Check whether this wrapper actually wraps an object. More...

	operator bool () const
	Check whether this wrapper actually wraps an object. More...

bool	operator== (const proxy_t &right) const
	Check whether two wrappers refer to the same object. More...

bool	operator!= (const proxy_t &right) const
	Check whether two wrappers refer to different objects. More...

void	proxy_release ()
	Release the wrapped object (if any), making this an empty wrapper. More...

Static Public Attributes
static constexpr std::uint32_t	accept_since_version = 1
	Minimum protocol version required for the accept function. More...

static constexpr std::uint32_t	receive_since_version = 1
	Minimum protocol version required for the receive function. More...

static constexpr std::uint32_t	finish_since_version = 3
	Minimum protocol version required for the finish function. More...

static constexpr std::uint32_t	set_actions_since_version = 3
	Minimum protocol version required for the set_actions function. More...

Detailed Description

offer to transfer data

A wl_data_offer represents a piece of data offered for transfer by another client (the source client). It is used by the copy-and-paste and drag-and-drop mechanisms. The offer describes the different mime types that the data can be converted to and provides the mechanism for transferring the data directly from the source client.

Definition at line 656 of file wayland-client-protocol.hpp.

Member Enumeration Documentation

◆ wrapper_type

enum wayland::proxy_t::wrapper_type

stronginherited

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 105 of file wayland-client.hpp.

Member Function Documentation

◆ accept()

void data_offer_t::accept	(	uint32_t	serial,
		std::string	mime_type
	)

accept one of the offered mime types

Parameters

serial	serial number of the accept request
mime_type	mime type accepted by the client

Indicate that the client can accept the given mime type, or NULL for not accepted.

For objects of version 2 or older, this request is used by the client to give feedback whether the client can receive the given mime type, or NULL if none is accepted; the feedback does not determine whether the drag-and-drop operation succeeds or not.

For objects of version 3 or newer, this request determines the final result of the drag-and-drop operation. If the end result is that no mime types were accepted, the drag-and-drop operation will be cancelled and the corresponding drag source will receive wl_data_source.cancelled. Clients may still use this event in conjunction with wl_data_source.action for feedback.

Definition at line 1984 of file wayland-client-protocol.cpp.

◆ c_ptr()

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

◆ can_finish()

bool data_offer_t::can_finish ( ) const

Check whether the finish function is available with the currently bound version of the protocol.

Definition at line 1998 of file wayland-client-protocol.cpp.

◆ can_set_actions()

bool data_offer_t::can_set_actions ( ) const

Check whether the set_actions function is available with the currently bound version of the protocol.

Definition at line 2007 of file wayland-client-protocol.cpp.

◆ finish()

void data_offer_t::finish ( )

the offer will no longer be used

Notifies the compositor that the drag destination successfully finished the drag-and-drop operation.

Upon receiving this request, the compositor will emit wl_data_source.dnd_finished on the drag source client.

It is a client error to perform other requests than wl_data_offer.destroy after this one. It is also an error to perform this request after a NULL mime type has been set in wl_data_offer.accept or no action was received through wl_data_offer.action.

If wl_data_offer.finish request is received for a non drag and drop operation, the invalid_finish protocol error is raised.

Definition at line 1994 of file wayland-client-protocol.cpp.

◆ get_class()

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

◆ get_id()

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

Examples: dump.cpp.

◆ get_version()

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

◆ get_wrapper_type()

wrapper_type wayland::proxy_t::get_wrapper_type ( ) const

inlineinherited

Get the type of a proxy object.

Definition at line 288 of file wayland-client.hpp.

◆ on_action()

std::function< void(data_device_manager_dnd_action)> & data_offer_t::on_action ( )

notify the selected action

Parameters

dnd_action action selected by the compositor

This event indicates the action selected by the compositor after matching the source/destination side actions. Only one action (or none) will be offered here.

This event can be emitted multiple times during the drag-and-drop operation in response to destination side action changes through wl_data_offer.set_actions.

This event will no longer be emitted after wl_data_device.drop happened on the drag-and-drop destination, the client must honor the last action received, or the last preferred one set through wl_data_offer.set_actions when handling an "ask" action.

Compositors may also change the selected action on the fly, mainly in response to keyboard modifier changes during the drag-and-drop operation.

The most recent action received is always the valid one. Prior to receiving wl_data_device.drop, the chosen action may change (e.g. due to keyboard modifiers being pressed). At the time of receiving wl_data_device.drop the drag-and-drop destination must honor the last action received.

Action changes may still happen after wl_data_device.drop, especially on "ask" actions, where the drag-and-drop destination may choose another action afterwards. Action changes happening at this stage are always the result of inter-client negotiation, the compositor shall no longer be able to induce a different action.

Upon "ask" actions, it is expected that the drag-and-drop destination may potentially choose a different action and/or mime type, based on wl_data_offer.source_actions and finally chosen by the user (e.g. popping up a menu with the available options). The final wl_data_offer.set_actions and wl_data_offer.accept requests must happen before the call to wl_data_offer.finish.

Definition at line 2022 of file wayland-client-protocol.cpp.

◆ on_offer()

std::function< void(std::string)> & data_offer_t::on_offer ( )

advertise offered mime type

Parameters

mime_type offered mime type

Sent immediately after creating the wl_data_offer object. One event per offered mime type.

Definition at line 2012 of file wayland-client-protocol.cpp.

◆ on_source_actions()

std::function< void(data_device_manager_dnd_action)> & data_offer_t::on_source_actions ( )

notify the source-side available actions

Parameters

source_actions actions offered by the data source

This event indicates the actions offered by the data source. It will be sent right after wl_data_device.enter, or anytime the source side changes its offered actions through wl_data_source.set_actions.

Definition at line 2017 of file wayland-client-protocol.cpp.

◆ operator bool()

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

◆ operator!=()

bool wayland::proxy_t::operator!= ( const proxy_t & right ) const

inherited

Check whether two wrappers refer to different objects.

◆ operator==()

bool wayland::proxy_t::operator== ( const proxy_t & right ) const

inherited

Check whether two wrappers refer to the same object.

◆ proxy_has_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

◆ proxy_release()

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.

◆ receive()

void data_offer_t::receive	(	std::string	mime_type,
		int	fd
	)

request that the data is transferred

Parameters

mime_type	mime type desired by receiver
fd	file descriptor for data transfer

To transfer the offered data, the client issues this request and indicates the mime type it wants to receive. The transfer happens through the passed file descriptor (typically created with the pipe system call). The source client writes the data in the mime type representation requested and then closes the file descriptor.

The receiving client reads from the read end of the pipe until EOF and then closes its end, at which point the transfer is complete.

This request may happen multiple times for different mime types, both before and after wl_data_device.drop. Drag-and-drop destination clients may preemptively fetch data or examine it more closely to determine acceptance.

Definition at line 1989 of file wayland-client-protocol.cpp.

◆ set_actions()

void data_offer_t::set_actions	(	data_device_manager_dnd_action	dnd_actions,
		data_device_manager_dnd_action	preferred_action
	)

set the available/preferred drag-and-drop actions

Parameters

dnd_actions	actions supported by the destination client
preferred_action	action preferred by the destination client

Sets the actions that the destination side client supports for this operation. This request may trigger the emission of wl_data_source.action and wl_data_offer.action events if the compositor needs to change the selected action.

This request can be called multiple times throughout the drag-and-drop operation, typically in response to wl_data_device.enter or wl_data_device.motion events.

This request determines the final result of the drag-and-drop operation. If the end result is that no action is accepted, the drag source will receive wl_drag_source.cancelled.

The dnd_actions argument must contain only values expressed in the wl_data_device_manager.dnd_actions enum, and the preferred_action argument must only contain one of those values set, otherwise it will result in a protocol error.

While managing an "ask" action, the destination drag-and-drop client may perform further wl_data_offer.receive requests, and is expected to perform one last wl_data_offer.set_actions request with a preferred action other than "ask" (and optionally wl_data_offer.accept) before requesting wl_data_offer.finish, in order to convey the action selected by the user. If the preferred action is not in the wl_data_offer.source_actions mask, an error will be raised.

If the "ask" action is dismissed (e.g. user cancellation), the client is expected to perform wl_data_offer.destroy right away.

This request can only be made on drag-and-drop offers, a protocol error will be raised otherwise.

Definition at line 2003 of file wayland-client-protocol.cpp.

◆ set_queue()

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.

Member Data Documentation

◆ accept_since_version

constexpr std::uint32_t wayland::data_offer_t::accept_since_version = 1

staticconstexpr

Minimum protocol version required for the accept function.

Definition at line 705 of file wayland-client-protocol.hpp.

◆ finish_since_version

constexpr std::uint32_t wayland::data_offer_t::finish_since_version = 3

staticconstexpr

Minimum protocol version required for the finish function.

Definition at line 756 of file wayland-client-protocol.hpp.

◆ receive_since_version

constexpr std::uint32_t wayland::data_offer_t::receive_since_version = 1

staticconstexpr

Minimum protocol version required for the receive function.

Definition at line 732 of file wayland-client-protocol.hpp.

◆ set_actions_since_version

constexpr std::uint32_t wayland::data_offer_t::set_actions_since_version = 3

staticconstexpr

Minimum protocol version required for the set_actions function.

Definition at line 804 of file wayland-client-protocol.hpp.

The documentation for this class was generated from the following files:

build/wayland-client-protocol.hpp
build/wayland-client-protocol.cpp

Public Types

Public Member Functions

Static Public Attributes

Detailed Description

Member Enumeration Documentation

◆ wrapper_type

Member Function Documentation

◆ accept()

◆ c_ptr()

◆ can_finish()

◆ can_set_actions()

◆ finish()

◆ get_class()

◆ get_id()

◆ get_version()

◆ get_wrapper_type()

◆ on_action()

◆ on_offer()

◆ on_source_actions()

◆ operator bool()

◆ operator!=()

◆ operator==()

◆ proxy_has_object()

◆ proxy_release()

◆ receive()

◆ set_actions()

◆ set_queue()

Member Data Documentation

◆ accept_since_version

◆ finish_since_version

◆ receive_since_version

◆ set_actions_since_version