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@jsvision/ui / Editor

Class: Editor

Documented in: Editor

Defined in: ui/src/editor/editor.ts:72

A focusable, scrollable multiline text editor. Add it to a Group, give it a size, and drive it via the event loop or programmatically (setText/getText/insertText/ execute). The reactive signals (curPos, modified, canUndo, …) drive a status line/indicator. Share Cut/Copy/Paste by passing one Editor as the clipboard of each (see EditorOptions); for scroll bars + a line/column indicator use EditWindow.

Example

ts
import { Group, Editor, createEventLoop, effect } from '@jsvision/ui';

const editor = new Editor({ clipboard: new Editor() });
const root = new Group();
root.add(editor);

const loop = createEventLoop({ width: 60, height: 20 }, {});
loop.mount(root);
loop.focusView(editor);
editor.setText('The quick brown fox\nSecond line.');
effect(() => {
  const { line, col } = editor.curPos();
  console.log(`caret at ${line}:${col}`);
});

Extends

Extended by

Constructors

Constructor

new Editor(options?): Editor

Defined in: ui/src/editor/editor.ts:138

Parameters

options?

EditorOptions = {}

Returns

Editor

Overrides

View.constructor

Properties

autoIndentOn

autoIndentOn: boolean

Defined in: ui/src/editor/editor.ts:104


bounds

bounds: Rect

Defined in: ui/src/view/view.ts:65

Parent-relative integer rect; written by the layout pass — read it in draw/hit-testing.

Inherited from

View.bounds


canRedo

readonly canRedo: Signal<boolean>

Defined in: ui/src/editor/editor.ts:90


canUndo

readonly canUndo: Signal<boolean>

Defined in: ui/src/editor/editor.ts:89

Whether an undo / redo step is available.


castsShadow

castsShadow: boolean = false

Defined in: ui/src/view/view.ts:78

When true, the renderer paints a drop shadow on the cells just below and to the right of this view, in paint order (a later sibling's shadow falls over an earlier one). Default false. The Desktop sets it per window.

Inherited from

View.castsShadow


centered

centered: boolean = false

Defined in: ui/src/view/view.ts:86

When true, the layout pass recentres this view within its parent after layout — origin = (parent - self) / 2 on both axes. Intended for absolutely-placed views (a modal dialog, a message box) whose size is fixed and whose origin would otherwise be placed by the caller. Default false; Dialog sets it when centered.

Inherited from

View.centered


curPos

readonly curPos: Signal<{ col: number; line: number; }>

Defined in: ui/src/editor/editor.ts:81

The caret as 1-based {line, col} (col is the visual column).


curPtr

curPtr: number = 0

Defined in: ui/src/editor/editor.ts:98


curY

curY: number = 0

Defined in: ui/src/editor/editor.ts:107


delta

readonly delta: object

Defined in: ui/src/editor/editor.ts:92

The scroll offset, as a pair of signals — also the value channel for scroll bars: a bar bound to delta.x/delta.y scrolls the editor on any write (clamped to the content).

x

readonly x: Signal<number>

y

readonly y: Signal<number>


doReplace

doReplace: boolean = false

Defined in: ui/src/editor/editor.ts:252


drawLine

drawLine: number = 0

Defined in: ui/src/editor/editor.ts:108


drawPtrP

drawPtrP: number = 0

Defined in: ui/src/editor/editor.ts:109


eolKind

eolKind: LineEnding = 'lf'

Defined in: ui/src/editor/editor.ts:97


focusable

focusable: boolean = true

Defined in: ui/src/editor/editor.ts:73

Whether this view can receive keyboard focus. Effective focusability also requires the view to be visible and enabled with no hidden/disabled ancestor. Default false; the focus manager drives the state.focused flag.

Overrides

View.focusable


hasSelection

readonly hasSelection: Signal<boolean>

Defined in: ui/src/editor/editor.ts:83

Whether any text is currently selected.


indicator

indicator: IndicatorTarget | null = null

Defined in: ui/src/editor/editor.ts:132


insertMode

readonly insertMode: Signal<boolean>

Defined in: ui/src/editor/editor.ts:85

true = insert mode, false = overwrite mode; the Insert key toggles it.


keyBindings

readonly keyBindings: EditorKeyBindings

Defined in: ui/src/editor/editor.ts:113


layout

layout: LayoutProps = {}

Defined in: ui/src/view/view.ts:69

Layout props for this view (direction, size, padding, absolute placement, …).

Inherited from

View.layout


limitY

limitY: number = 1

Defined in: ui/src/editor/editor.ts:110


lineCount

readonly lineCount: Signal<number>

Defined in: ui/src/editor/editor.ts:87

The number of lines in the buffer.


modified

readonly modified: Signal<boolean>

Defined in: ui/src/editor/editor.ts:79

Whether the buffer has unsaved changes since it was last loaded or saved.


normalRole

protected normalRole: keyof Theme = 'editorNormal'

Defined in: ui/src/editor/editor.ts:135

The normal/selected theme roles; Memo overrides them to the gray-dialog palette.


options

readonly options: EditorOptions

Defined in: ui/src/editor/editor.ts:118


overwrite

overwrite: boolean

Defined in: ui/src/editor/editor.ts:103


postProcess

postProcess: boolean = false

Defined in: ui/src/view/view.ts:98

Take part in the post-process sweep (after the focused view sees the event).

Inherited from

View.postProcess


preProcess

preProcess: boolean = true

Defined in: ui/src/editor/editor.ts:75

Sees keys before app chrome so the focused editor can claim the WordStar Ctrl-Q/Ctrl-K prefixes.

Overrides

View.preProcess


promptOnReplace

promptOnReplace: boolean = true

Defined in: ui/src/editor/editor.ts:250


replaceAllFlag

replaceAllFlag: boolean = false

Defined in: ui/src/editor/editor.ts:251


replaceStr

replaceStr: string = ''

Defined in: ui/src/editor/editor.ts:248


searchOpts

searchOpts: SearchOptions

Defined in: ui/src/editor/editor.ts:249


selectedRole

protected selectedRole: keyof Theme = 'editorSelected'

Defined in: ui/src/editor/editor.ts:136


selecting

selecting: boolean = false

Defined in: ui/src/editor/editor.ts:102


selEndP

selEndP: number = 0

Defined in: ui/src/editor/editor.ts:101


state

readonly state: ViewState

Defined in: ui/src/view/view.ts:67

Draw-against flags. The object reference is fixed; individual fields mutate (e.g. focused).

Inherited from

View.state


undoStack

readonly undoStack: UndoStack

Defined in: ui/src/editor/editor.ts:121


vBar

vBar: GadgetBar | null = null

Defined in: ui/src/editor/editor.ts:131

Methods

accelerators()

accelerators(): readonly string[]

Defined in: ui/src/view/view.ts:114

The Alt+hotkey accelerator characters (lowercase) this view claims in its focus scope, for duplicate-accelerator detection. The base returns none; accelerator-bearing widgets (Button/Label/CheckGroup/RadioGroup) override it to report their ~X~ hotkey(s).

Returns

readonly string[]

The claimed accelerator chars, or an empty list when the view claims none.

Inherited from

View.accelerators


attachGadgets()

attachGadgets(h?, v?, ind?): void

Defined in: ui/src/editor/editor.ts:228

Wire up the scroll bars and line/column indicator that display and drive this editor.

Parameters

h?

GadgetBar

v?

GadgetBar

ind?

IndicatorTarget

Returns

void


bind()

bind<T>(reader, apply?, opts?): void

Defined in: ui/src/view/view.ts:228

Bind a reactive value to a redraw. Creates an effect (owned by this view's scope) that reads reader() — subscribing to whatever signals it touches — runs the optional apply(value), then requests a frame: a repaint by default, or a reflow when { relayout: true }. It re-runs automatically whenever those signals change, and is disposed when the view unmounts.

Call it from onMount, not the constructor — the view's scope only exists once mounted, so a pre-mount bind throws rather than silently dropping the binding.

Type Parameters

T

T

Parameters

reader

() => T

Reads the reactive source; the signals it reads become dependencies.

apply?

(v) => void

Optional: apply the read value to the widget (e.g. store it in a field).

opts?

Pass { relayout: true } when the change affects layout, so it reflows instead of just repainting.

relayout?

boolean

Returns

void

Example

ts
import { signal } from '@jsvision/ui';

const count = signal(0);
// `status` is a View whose draw() reads count():
status.onMount(() => {
  status.bind(() => count()); // repaint the status line whenever `count` changes
});

Inherited from

View.bind


copy()

copy(): void

Defined in: ui/src/editor/editor.ts:278

Copy the selection to the shared clipboard editor (and the OS clipboard when supported).

Returns

void


cut()

cut(): void

Defined in: ui/src/editor/editor.ts:283

Cut the selection to the shared clipboard editor, as one undo step.

Returns

void


deleteSelect()

deleteSelect(): void

Defined in: ui/src/editor/editor.ts:416

Returns

void


derived()

protected derived<T>(fn): () => T

Defined in: ui/src/view/view.ts:261

Create a stable derived accessor owned by this view's scope. The returned () => T keeps the same identity for the life of the view, so it is safe to build in the constructor and hand to child views before this view mounts. The backing computed is created lazily under the view's own scope, so it is always owned and disposed at unmount — unlike a bare computed() in the constructor, which would run before any scope exists, leak, and warn.

Reads behave sensibly across the lifecycle:

  • Before mount: evaluates fn() directly (correct current value, nothing persisted). Good for a pre-mount natural-size measure.
  • After mount: builds and memoizes a computed(fn) under the view's scope.
  • After an unmount→remount: the memo is keyed to the scope it was built under, so a remounted view (which gets a fresh scope) re-derives under the new scope instead of returning the previous mount's disposed, now-frozen computed — keeping a Show/For-remounted widget reactive.

Type Parameters

T

T

Parameters

fn

() => T

The derivation (pure; the signals it reads become the computed's dependencies).

Returns

A stable accessor; call it to read the derived value.

() => T

Inherited from

View.derived


desiredCaret()

desiredCaret(): Point | null

Defined in: ui/src/editor/editor.ts:236

The hardware-caret cell (view-local) while focused and in view, else null.

Returns

Point | null

Overrides

View.desiredCaret


doSearchReplace()

doSearchReplace(): Promise<number>

Defined in: ui/src/editor/editor.ts:273

Returns

Promise<number>


draw()

draw(ctx): void

Defined in: ui/src/editor/editor.ts:486

Paint the visible rows.

Parameters

ctx

DrawContext

Returns

void

Overrides

View.draw


execute()

execute(action): void

Defined in: ui/src/editor/editor.ts:223

Run one editor action programmatically — the same operations the keymap triggers.

Parameters

action

EditorAction

The action to run (e.g. 'lineDown', 'undo', 'textEnd', 'selectAll').

Returns

void

Example

ts
editor.setText('hello world');
editor.execute('textEnd'); // caret to end of buffer

find()

find(): Promise<void>

Defined in: ui/src/editor/editor.ts:255

Open the Find dialog and search for the first match. Resolves when the interaction is done.

Returns

Promise<void>


focusSignal()

focusSignal(): Signal<void>

Defined in: ui/src/view/view.ts:136

Subscribe to this view's focus changes. Reading the returned signal inside a bind/effect re-runs that effect whenever this view gains or loses focus — including from another view (e.g. a Label repainting when the control it labels is focused). The signal notifies on every poke even without a value change. Lazy: the backing signal is created on first call.

Returns

Signal<void>

A signal that ticks whenever this view gains or loses focus.

Example

ts
// Inside a widget's onMount, repaint whenever `other` view's focus changes:
this.onMount(() => this.bind(() => other.focusSignal()()));

Inherited from

View.focusSignal


getMousePtr()

getMousePtr(local): number

Defined in: ui/src/editor/editor.ts:469

Parameters

local

Point

Returns

number


getText()

getText(range?): string

Defined in: ui/src/editor/editor.ts:197

The full buffer content, or the text in a [from, to) range — returned verbatim.

Parameters

range?

Optional half-open buffer-offset range; omit for the whole buffer.

from

number

to

number

Returns

string

The requested text.


insertText()

insertText(text): void

Defined in: ui/src/editor/editor.ts:206

Insert text at the caret, replacing any selection; line endings are normalized to the buffer's kind, as if typed.

Parameters

text

string

The text to insert.

Returns

void


invalidate()

invalidate(): void

Defined in: ui/src/view/view.ts:197

Request a repaint of this view. A no-op before the view is mounted (the first frame paints everything).

Returns

void

Inherited from

View.invalidate


invalidateLayout()

invalidateLayout(): void

Defined in: ui/src/view/view.ts:202

Request a reflow (re-run layout, then repaint). Use this when a change affects size/position, not just pixels.

Returns

void

Inherited from

View.invalidateLayout


measure()?

optional measure(available): Size2D

Defined in: ui/src/view/view.ts:71

Optional intrinsic-size hook for auto sizing — return the size this view wants for available.

Parameters

available

Size2D

Returns

Size2D

Inherited from

View.measure


onCleanup()

onCleanup(fn): void

Defined in: ui/src/view/view.ts:298

Register a teardown callback that runs once when this view unmounts. Requires a mounted view — so call it from within onMount. Use it to release anything the view acquired (a timer, an external subscription).

Parameters

fn

() => void

The teardown callback.

Returns

void

Inherited from

View.onCleanup


onEvent()

onEvent(ev): void

Defined in: ui/src/editor/editor.ts:491

Handle a dispatched event (keys, mouse/wheel, paste, and editing commands).

Parameters

ev

DispatchEvent

Returns

void

Overrides

View.onEvent


onMount()

onMount(fn): void

Defined in: ui/src/view/view.ts:283

Register a callback to run once when the view becomes live (after its first layout gives it bounds). This is where to call bind, since the view's reactive scope exists by then. Registering after the view is already live runs the callback immediately.

Parameters

fn

() => void

Post-mount setup.

Returns

void

Inherited from

View.onMount


paste()

paste(): void

Defined in: ui/src/editor/editor.ts:288

Paste the shared clipboard editor's selection at the caret, as one undo step.

Returns

void


redo()

redo(): void

Defined in: ui/src/editor/editor.ts:298

Redo the most recently undone edit.

Returns

void


replace()

replace(): Promise<number>

Defined in: ui/src/editor/editor.ts:260

Open the Replace dialog and run the replace loop; resolves with the number of replacements made.

Returns

Promise<number>


scrollTo()

scrollTo(x, y): void

Defined in: ui/src/editor/editor.ts:460

Parameters

x

number

y

number

Returns

void


searchAgain()

searchAgain(): Promise<number>

Defined in: ui/src/editor/editor.ts:265

Repeat the last search/replace with the stored parameters; resolves with the replacement count.

Returns

Promise<number>


searchOnce()

searchOnce(): boolean

Defined in: ui/src/editor/editor.ts:269

Returns

boolean


selectByClick()?

optional selectByClick(): void

Defined in: ui/src/view/view.ts:182

Optional "select + raise on click" hook. Left undefined on the base, so a plain view is not a select/raise target. A container that owns z-order (a Window) overrides it to select and raise itself. The hit-test invokes the first ancestor that defines this — before delivering the mouse-down — so a click always raises the window even if the interior also consumes the click.

Returns

void

Inherited from

View.selectByClick


selectionText()

selectionText(): string

Defined in: ui/src/editor/editor.ts:212

The currently selected text, or '' when there is no selection.

Returns

string


setText()

setText(text): void

Defined in: ui/src/editor/editor.ts:171

Replace the entire content (verbatim, mixed line endings preserved); the line-ending kind is re-detected and cursor/selection/scroll/undo history are reset.

Parameters

text

string

The new buffer content.

Returns

void


toggleInsMode()

toggleInsMode(): void

Defined in: ui/src/editor/editor.ts:454

Returns

void


undo()

undo(): void

Defined in: ui/src/editor/editor.ts:293

Undo the most recent edit.

Returns

void


viewH()

viewH(): number

Defined in: ui/src/editor/editor.ts:308

Returns

number