Skip to main content

DataTransfer

Struct DataTransfer 

pub struct DataTransfer { /* private fields */ }
Expand description

DataTransfer abstracts over the various ways of transferring data within an application and between applications.

The details will depend on the current platform, but the common features are:

  • Each DataTransfer contains multiple views over the same data in different formats
  • The DataTransfer may contain an in-memory representation of the data, which can be sent and received within the current application
  • Serializing to/deserializing from a given format may be done eagerly or lazily1

Currently, only plaintext and image data is supported. Precisely how this maps to the backend will depend on platform and features. Work to expand this API is ongoing, see the tracking issue for drag-and-drop to follow its progress.

The easiest way to construct this type is with the Default implementation, followed by set_plaintext or set_image. There are also implementations of From<SharedString> and From<Image> which construct a new DataTransfer using those methods respectively. The opposites of these operations are fetch_plaintext and fetch_image.


let message = "Hello, world!";
let data = DataTransfer::from(message.to_shared_string());
assert_eq!(data.fetch_plaintext().unwrap(), message);

  1. Platforms differ on which formats can and cannot be lazy, but all support it in some capacity. Reading data from a DataTransfer cannot be assumed to be a cheap operation. 

Implementations§

§

impl DataTransfer

pub fn set_image(&mut self, image: Image) -> &mut DataTransfer

Sets an image to be transferred by this DataTransfer.

The image can be read using fetch_image. If you only need the DataTransfer to have an image representation, use From<Image>.

Each DataTransfer can only have a single image set at once. If this method is called multiple times, the previous image will be overwritten. However, you can have, for example, both an image representation and a plaintext representation set simultaneously on the same DataTransfer.

pub fn set_plaintext(&mut self, plaintext: SharedString) -> &mut DataTransfer

Sets unstyled, basic text to be transferred by this DataTransfer.

The image can be read using fetch_plaintext. If you only need the DataTransfer to have a plaintext representation, use From<SharedString>.

Each DataTransfer can only have a single plaintext representiation set at once. If this method is called multiple times, the previous text will be overwritten. However, you can have, for example, both an image representation and a plaintext representation set simultaneously on the same DataTransfer.

pub fn has_image(&self) -> bool

Returns true if this data transfer advertises that it is readable as an Image.

This does not necessarily mean that fetch_image will return Ok, as an I/O error may occur.

pub fn has_plaintext(&self) -> bool

Returns true if this data transfer advertises that it is readable as plaintext.

This does not necessarily mean that fetch_plaintext will return Ok, as an I/O error may occur.

pub fn set_user_data(&mut self, value: Rc<dyn Any>) -> &mut DataTransfer

Set the application-internal data represented by this DataTransfer. This can be read with DataTransfer::user_data, and allows circumventing serialize/deserializing the data to bytes when a drag-and-drop or copy-paste operation stays within the application.

pub fn fetch_plaintext(&self) -> Result<SharedString, DataTransferError>

Helper to read this DataTransfer as plaintext, supporting multiple encodings.

The caller should assume that this method call may do I/O.

pub fn fetch_image(&self) -> Result<Image, DataTransferError>

Helper to read this DataTransfer as an image, supporting multiple image types.

The caller should assume that this method call may do I/O.

pub fn user_data(&self) -> Option<Rc<dyn Any>>

Get the application-internal data represented by this DataTransfer, if one exists.

Trait Implementations§

§

impl Clone for DataTransfer

§

fn clone(&self) -> DataTransfer

Returns a duplicate of the value. Read more
1.0.0 (const: unstable) · Source§

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more
§

impl Debug for DataTransfer

§

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

Formats the value using the given formatter. Read more
§

impl Default for DataTransfer

§

fn default() -> DataTransfer

Returns the “default value” for a type. Read more
Source§

impl From<DataTransfer> for Value

Source§

fn from(v: DataTransfer) -> Value

Converts to this type from the input type.
§

impl From<Image> for DataTransfer

§

fn from(value: Image) -> DataTransfer

Converts to this type from the input type.
§

impl From<SharedString> for DataTransfer

§

fn from(value: SharedString) -> DataTransfer

Converts to this type from the input type.
§

impl PartialEq for DataTransfer

§

fn eq(&self, other: &DataTransfer) -> bool

Tests for self and other values to be equal, and is used by ==.
1.0.0 (const: unstable) · Source§

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
Source§

impl TryFrom<Value> for DataTransfer

Source§

type Error = Value

The type returned in the event of a conversion error.
Source§

fn try_from( v: Value, ) -> Result<DataTransfer, <DataTransfer as TryFrom<Value>>::Error>

Performs the conversion.

Auto Trait Implementations§

Blanket Implementations§

Source§

impl<T> Any for T
where T: 'static + ?Sized,

Source§

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
Source§

impl<T> Borrow<T> for T
where T: ?Sized,

Source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
Source§

impl<T> BorrowMut<T> for T
where T: ?Sized,

Source§

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
Source§

impl<T> CloneToUninit for T
where T: Clone,

Source§

unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (clone_to_uninit)
Performs copy-assignment from self to dest. Read more
§

impl<T> Downcast<T> for T

§

fn downcast(&self) -> &T

§

impl<T> Downcast for T
where T: Any,

§

fn into_any(self: Box<T>) -> Box<dyn Any>

Convert Box<dyn Trait> (where Trait: Downcast) to Box<dyn Any>. Box<dyn Any> can then be further downcast into Box<ConcreteType> where ConcreteType implements Trait.
§

fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>

Convert Rc<Trait> (where Trait: Downcast) to Rc<Any>. Rc<Any> can then be further downcast into Rc<ConcreteType> where ConcreteType implements Trait.
§

fn as_any(&self) -> &(dyn Any + 'static)

Convert &Trait (where Trait: Downcast) to &Any. This is needed since Rust cannot generate &Any’s vtable from &Trait’s.
§

fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)

Convert &mut Trait (where Trait: Downcast) to &Any. This is needed since Rust cannot generate &mut Any’s vtable from &mut Trait’s.
Source§

impl<T> From<T> for T

Source§

fn from(t: T) -> T

Returns the argument unchanged.

§

impl<T> Instrument for T

§

fn instrument(self, span: Span) -> Instrumented<Self>

Instruments this type with the provided [Span], returning an Instrumented wrapper. Read more
§

fn in_current_span(self) -> Instrumented<Self>

Instruments this type with the current Span, returning an Instrumented wrapper. Read more
Source§

impl<T, U> Into<U> for T
where U: From<T>,

Source§

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Source§

impl<T> IntoEither for T

Source§

fn into_either(self, into_left: bool) -> Either<Self, Self>

Converts self into a Left variant of Either<Self, Self> if into_left is true. Converts self into a Right variant of Either<Self, Self> otherwise. Read more
Source§

fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
where F: FnOnce(&Self) -> bool,

Converts self into a Left variant of Either<Self, Self> if into_left(&self) returns true. Converts self into a Right variant of Either<Self, Self> otherwise. Read more
§

impl<T> NoneValue for T
where T: Default,

§

type NoneType = T

§

fn null_value() -> T

The none-equivalent value.
§

impl<T> Pointable for T

§

const ALIGN: usize

The alignment of pointer.
§

type Init = T

The type for initializers.
§

unsafe fn init(init: <T as Pointable>::Init) -> usize

Initializes a with the given initializer. Read more
§

unsafe fn deref<'a>(ptr: usize) -> &'a T

Dereferences the given pointer. Read more
§

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

Mutably dereferences the given pointer. Read more
§

unsafe fn drop(ptr: usize)

Drops the object pointed to by the given pointer. Read more
Source§

impl<R, P> ReadPrimitive<R> for P
where R: Read + ReadEndian<P>, P: Default,

Source§

fn read_from_little_endian(read: &mut R) -> Result<Self, Error>

Read this value from the supplied reader. Same as ReadEndian::read_from_little_endian().
Source§

fn read_from_big_endian(read: &mut R) -> Result<Self, Error>

Read this value from the supplied reader. Same as ReadEndian::read_from_big_endian().
Source§

fn read_from_native_endian(read: &mut R) -> Result<Self, Error>

Read this value from the supplied reader. Same as ReadEndian::read_from_native_endian().
Source§

impl<T> Same for T

Source§

type Output = T

Should always be Self
§

impl<SS, SP> SupersetOf<SS> for SP
where SS: SubsetOf<SP>,

§

fn to_subset(&self) -> Option<SS>

The inverse inclusion map: attempts to construct self from the equivalent element of its superset. Read more
§

fn is_in_subset(&self) -> bool

Checks if self is actually part of its subset T (and can be converted to it).
§

fn to_subset_unchecked(&self) -> SS

Use with care! Same as self.to_subset but without any property checks. Always succeeds.
§

fn from_subset(element: &SS) -> SP

The inclusion map: converts self to the equivalent element of its superset.
Source§

impl<T> ToOwned for T
where T: Clone,

Source§

type Owned = T

The resulting type after obtaining ownership.
Source§

fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
Source§

fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
Source§

impl<T, U> TryFrom<U> for T
where U: Into<T>,

Source§

type Error = Infallible

The type returned in the event of a conversion error.
Source§

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
Source§

impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

Source§

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
Source§

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
§

impl<T> Upcast<T> for T

§

fn upcast(&self) -> Option<&T>

§

impl<T> WithSubscriber for T

§

fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>
where S: Into<Dispatch>,

Attaches the provided Subscriber to this type, returning a [WithDispatch] wrapper. Read more
§

fn with_current_subscriber(self) -> WithDispatch<Self>

Attaches the current default Subscriber to this type, returning a [WithDispatch] wrapper. Read more
§

impl<T> Brush for T
where T: Clone + PartialEq + Default + Debug,

§

impl<T> ErasedDestructor for T
where T: 'static,

Source§

impl<T> Scalar for T
where T: 'static + Clone + PartialEq + Debug,