pub enum EventPayload<'a> {
Show 50 variants
Clicked,
TextChanged(&'a str),
TextSubmitted(&'a str),
FocusLost,
ProtocolError {
code: u32,
message: &'a str,
},
KeyDown {
key: Key,
shift_key: bool,
ctrl_key: bool,
alt_key: bool,
meta_key: bool,
repeat: bool,
code: u32,
text: &'a str,
},
RangeRequested {
start: u32,
count: u32,
},
ValueChanged(f64),
WindowSizeChanged {
width_dp: f32,
height_dp: f32,
class: WindowSizeClass,
height_class: WindowHeightClass,
safe_area_top: f32,
safe_area_leading: f32,
safe_area_trailing: f32,
},
FilesEntered,
FilesDropped(&'a str),
DesignSystemResolved(DesignSystem),
Resync,
LifecycleStart,
LifecycleStop,
NotificationActivated {
action: u32,
key: &'a str,
},
NotificationPermissionChanged(NotificationPermission),
CodeChanged {
version: u32,
start_line: u32,
start_column: u32,
end_line: u32,
end_column: u32,
text: &'a str,
},
CodeEditRejected {
request_id: u32,
base_version: u32,
current_version: u32,
start_line: u32,
start_column: u32,
end_line: u32,
end_column: u32,
},
CodeHovered {
decoration: u64,
line: u32,
column: u32,
phase: HoverPhase,
},
CodeSaveRequested {
version: u32,
},
DecorationActivated {
decoration: u64,
},
AnimationEvent {
animation_id: u32,
kind: AnimationEventKind,
property: AnimatedProperty,
slot: u8,
iteration: u32,
elapsed_ms: f32,
time_nanos: u64,
},
ReducedMotionChanged(ReducedMotion),
Pointer {Show 13 fields
kind: PointerKind,
pointer_id: u32,
pointer_type: PointerType,
x: f32,
y: f32,
buttons: u32,
button: u32,
modifiers: u32,
click_count: u32,
delta_x: f32,
delta_y: f32,
delta_mode: WheelDeltaMode,
timestamp_nanos: u64,
},
ZoomChanged {
k: f32,
os: f32,
level: i32,
},
SelectionChanged {
version: u32,
anchor_line: u32,
anchor_column: u32,
active_line: u32,
active_column: u32,
},
VisibleRangeChanged {
version: u32,
first_line: u32,
last_line: u32,
},
EditorFocusChanged {
focused: bool,
},
FoldChanged {
start_line: u32,
collapsed: bool,
},
CompositionChanged {
composing: bool,
},
WindowCloseRequested,
WindowFocusChanged {
focused: bool,
},
WindowMoved {
x: f32,
y: f32,
width: f32,
height: f32,
},
WindowDrag {
phase: u32,
screen_x: f32,
screen_y: f32,
over_window: u32,
},
WindowDragOver {
kind: u32,
window: u32,
x: f32,
y: f32,
},
WindowUnavailable,
WindowClosed,
WindowRequested {
key: &'a str,
request: u32,
},
ApplicationReopen,
FocusGained,
KeyUp {
key: Key,
shift_key: bool,
ctrl_key: bool,
alt_key: bool,
meta_key: bool,
repeat: bool,
code: u32,
text: &'a str,
},
CodeMetrics {
line_height_px: f64,
},
CodeScrolled {
offset_px: f64,
},
FileDialogResult {
request: u32,
status: FileDialogStatus,
filter: u32,
paths: &'a str,
},
ClipboardText {
request: u32,
status: u32,
len: u32,
text: &'a str,
},
IoAnswer {
request: u32,
status: IoStatus,
data: &'a [u8],
},
FileHandles {
request: u32,
status: FileDialogStatus,
filter: u32,
delivery: FileDelivery,
first_handle: u32,
names: &'a str,
kinds: &'a str,
},
StorageLocation(&'a str),
ScrollChanged {
item: u32,
settled: bool,
can_scroll_backward: bool,
can_scroll_forward: bool,
x_px: f64,
y_px: f64,
max_x_px: f64,
max_y_px: f64,
viewport_width_px: f64,
viewport_height_px: f64,
},
}Variants§
Clicked
TextChanged(&'a str)
TextSubmitted(&'a str)
FocusLost
ProtocolError
KeyDown
Fields
RangeRequested
The Renderer asks the Host to materialise the visible item range.
ValueChanged(f64)
A control’s new value, in the widget’s own unit: an epoch count for a picker, a position for a slider, 0.0 or 1.0 for a toggle. The Renderer decided how the user reached it, so nothing about calendars, wheels, tracks or thumbs crosses here.
One f64 holds all of them: integers up to 2^53 survive it exactly, so splitting
the event in two would only give the same concept two names.
WindowSizeChanged
The window, or one observed node, moved into a different size class. The Renderer
measures it and sends this only when a class changes, never on every layout pass.
A node_id of 0 is the window; anything else is the node that asked to be
measured.
FilesEntered
Files are over a node that said it would take them. Nothing about what they are: the platforms disagree about what is knowable before a drop, and a screen that only needs to light up does not need to know.
FilesDropped(&'a str)
Files were let go over a node. The paths arrive together, separated by a byte no path on any of the three desktops may contain.
DesignSystemResolved(DesignSystem)
The Renderer resolved the theme and this is what it chose. Sent once and then only when the answer changes, the same way a size class is.
Resync
The Renderer lost its node table and asks for the whole tree again. A recreated Activity is the case that produces it.
LifecycleStart
The platform brought the UI back. Timers and animations resume.
LifecycleStop
The platform stopped the UI. Timers and animations are suppressed, so a process that is not on screen is not asked to draw.
NotificationActivated
The user pressed a notification the application posted. action is 0 for the body
and 1 or 2 for an action button; key is the name the application gave it.
A name rather than a handler, because a notification outlives the component that posted it by hours and a callback dies with its scope.
NotificationPermissionChanged(NotificationPermission)
Whether notifications may be shown, sent once after start and then only when the answer changes.
CodeChanged
One committed edit to a code editor’s document.
The range is in the document as it stood before the edit, and version is the
version the edit produced. Lines and columns count from zero and columns are UTF-16
code units, which is what a language server counts in, so the event can be handed
to one unchanged. Text still being composed by an input method never arrives here:
only what the reader committed does.
CodeEditRejected
An edit the Host asked for and the Renderer did not apply, because the reader had changed the same place since the version the edit was written against.
Fields
CodeHovered
A pointer came to rest over a place in a code editor, or left it. decoration is
the id of the hover anchor under it, or zero where there is none.
CodeSaveRequested
The reader pressed the platform’s save shortcut on a code editor.
DecorationActivated
A decoration was pressed or accepted, named by the id the application gave it.
AnimationEvent
Something happened to an animation the Renderer is playing, sent only for the kinds the animation asked for. It names the node the animation plays on and no handler.
ReducedMotionChanged(ReducedMotion)
Whether the platform asks for reduced motion, sent once after start and then only when the answer changes.
Pointer
A pointer did something inside a node that subscribed to it. Coordinates are in dp
from the node’s top left corner, buttons is what is held now and button is the
one that caused a Down or an Up. timestamp_nanos is on the frame time’s clock.
ZoomChanged
How large the Renderer is drawing: k = os × 1.2^level. Sent once at start and
again whenever any of the three changes. A move to a screen of another density
changes none of them and is not reported.
SelectionChanged
The selection of a code editor moved, or an edit moved it. version is the document
version it is read against, the same series CodeChanged counts, and an edit’s
change always arrives first. Columns are UTF-16 units and never fall between the
two halves of a pair.
VisibleRangeChanged
The lines of a code editor that are on screen changed. Folded lines are skipped, so
first_line and last_line are the first and last lines the reader can see.
EditorFocusChanged
A code editor gained or lost the keyboard focus.
FoldChanged
The reader folded or unfolded the stretch that starts on start_line.
CompositionChanged
An input method started or ended a composition in a code editor. What is being composed stays in the Renderer: only the fact crosses.
WindowCloseRequested
The user asked to close a window. The window stays until the application removes its
Window node. Delivered to the node.
WindowFocusChanged
A window became the key window or stopped being it.
WindowMoved
A window’s outer frame moved or changed size, in screen dp. At most once a frame.
WindowDrag
A torn-off window being dragged. phase is 1 for a move, 2 for the end and 3 for a
cancel; over_window is the node id of the window under the pointer, or 0.
WindowDragOver
A dragged window passing over a node that has OnWindowDragOver. kind is 1 for
enter, 2 for move, 3 for leave and 4 for drop, window is the dragged window’s node
id, and the position is inside the node, in dp.
A window that could not be opened here: the platform has no second window, or it refused. Delivered once, to the node.
WindowClosed
The platform closed a window without asking. The window is already gone.
WindowRequested
A window the application has no node for yet, with the RestoreKey it was made
under (empty for a new one) and a request number. Delivered to the root.
ApplicationReopen
The user opened the application again while it had no window. Delivered to the root.
FocusGained
The node or a descendant inside it gained keyboard focus.
KeyUp
A key was released while the node held focus.
Fields
CodeMetrics
The height of one row of a code editor in physical pixels, as it is drawn. Sent when the editor is first drawn and whenever the height changes.
CodeScrolled
How far a code editor is scrolled down, in physical pixels. At most once a frame.
FileDialogResult
A file dialog ended. request is the number the Host gave it, filter is the
position of the filter in use (u32::MAX when there is none) and paths holds the
chosen paths separated by one NUL byte, empty unless the status is Chosen.
Delivered to the Host itself, with no node and no handler.
ClipboardText
One clipboard read ended. request is the number the Host gave it, status is a
word from clipboard::read_status, len is the text’s length in UTF-8 bytes and
text the text itself, empty unless the status is text. Delivered to the Host itself,
with no node and no handler.
IoAnswer
The one answer to an input or output request: a storage operation the browser
carried out, or an operation on a file picked on the web. request is the number
the Host gave it, and data is what the operation hands back: a value or a file
that was read, or the keys joined by NUL, and nothing for an operation that only
writes. Delivered to the Host itself, with no node and no handler.
FileHandles
Files the Renderer now holds handles for: the answer to a file dialog that was
chosen, or to a folder’s Entries or Child. The handles are first_handle,
first_handle + 1 and so on, one per name. names holds the names separated by one
NUL byte and kinds one letter per name, f for a file and d for a folder.
filter is the position of the filter in use, u32::MAX when there is none.
Delivered to the Host itself, with no node and no handler.
StorageLocation(&'a str)
Where the application’s storage lives on a platform whose Host cannot work it out
from the environment: Android’s application files directory, which only a
Context knows. Sent once by that Renderer at start. Delivered to the Host itself.
ScrollChanged
Where a scroll container is, reported by the Renderer to the node’s
OnScrollChanged handler: at most once a frame while it moves, and once more with
settled when it stops. Every length is in physical pixels, the unit the Renderer
scrolls in, so a value read here and sent back in a ScrollTo is the same place.
In a lazy list item is the first visible item and the main-axis offset is the
distance into that item; the list does not know its whole length, so its main-axis
max is -1.0. Elsewhere item is 0.