Enum wayland_server::protocol::wl_data_source::Event

#[non_exhaustive]
pub enum Event {
    Target {
        mime_type: Option<String>,
    },
    Send {
        mime_type: String,
        fd: RawFd,
    },
    Cancelled,
    DndDropPerformed,
    DndFinished,
    Action {
        dnd_action: DndAction,
    },
}

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Target

Fields

mime_type: Option<String>

a target accepts an offered mime type

Sent when a target accepts pointer_focus or motion events. If a target does not accept any of the offered types, type is NULL.

Used for feedback during drag-and-drop.

Send

Fields

mime_type: String

fd: RawFd

send the data

Request for data from the client. Send the data as the specified mime type over the passed file descriptor, then close it.

Cancelled

selection was cancelled

This data source is no longer valid. There are several reasons why this could happen:

• The data source has been replaced by another data source.
• The drag-and-drop operation was performed, but the drop destination did not accept any of the mime types offered through wl_data_source.target.
• The drag-and-drop operation was performed, but the drop destination did not select any of the actions present in the mask offered through wl_data_source.action.
• The drag-and-drop operation was performed but didn’t happen over a surface.
• The compositor cancelled the drag-and-drop operation (e.g. compositor dependent timeouts to avoid stale drag-and-drop transfers).

The client should clean up and destroy this data source.

For objects of version 2 or older, wl_data_source.cancelled will only be emitted if the data source was replaced by another data source.

DndDropPerformed

the drag-and-drop operation physically finished

The user performed the drop action. This event does not indicate acceptance, wl_data_source.cancelled may still be emitted afterwards if the drop destination does not accept any mime type.

However, this event might however not be received if the compositor cancelled the drag-and-drop operation before this event could happen.

Note that the data_source may still be used in the future and should not be destroyed here.

Only available since version 3 of the interface

DndFinished

the drag-and-drop operation concluded

The drop destination finished interoperating with this data source, so the client is now free to destroy this data source and free all associated data.

If the action used to perform the operation was “move”, the source can now delete the transferred data.

Only available since version 3 of the interface

Action

Fields

dnd_action: DndAction

notify the selected action

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, mainly in response to destination side changes through wl_data_offer.set_actions, and as the data device enters/leaves surfaces.

It is only possible to receive this event after wl_data_source.dnd_drop_performed if the drag-and-drop operation ended in an “ask” action, in which case the final wl_data_source.action event will happen immediately before wl_data_source.dnd_finished.

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. The chosen action may change alongside negotiation (e.g. an “ask” action can turn into a “move” operation), so the effects of the final action must always be applied in wl_data_offer.dnd_finished.

Clients can trigger cursor surface changes from this point, so they reflect the current action.

Only available since version 3 of the interface

Trait Implementations

impl Debug for Event

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl MessageGroup for Event

const MESSAGES: &'static [MessageDesc] = _

Wire representation of this MessageGroup

type Map = ResourceMap

The wrapper type for ObjectMap allowing the mapping of Object and NewId arguments to the object map during parsing.

fn is_destructor(&self) -> bool

Whether this message is a destructor

fn opcode(&self) -> u16

The opcode of this message

fn since(&self) -> u32

The minimal object version for which this message exists

fn child<Meta: ObjectMetadata>(
    opcode: u16,
    version: u32,
    meta: &Meta
) -> Option<Object<Meta>>

Retrieve the child Object associated with this message if any

fn from_raw(msg: Message, map: &mut Self::Map) -> Result<Self, ()>

Construct a message from its raw representation

fn into_raw(self, sender_id: u32) -> Message

Turn this message into its raw representation

unsafe fn from_raw_c(
    obj: *mut c_void,
    opcode: u32,
    args: *const wl_argument
) -> Result<Event, ()>

Construct a message of this group from its C representation

fn as_raw_c_in<F, T>(self, f: F) -> T where
    F: FnOnce(u32, &mut [wl_argument]) -> T, 

Build a C representation of this message