ConsoleForge.Widgets.TextArea Class Reference

A multi-line text input widget. More...

Inheritance diagram for ConsoleForge.Widgets.TextArea:

Public Member Functions
void	OnKeyEvent (KeyMsg key, Action< IMsg > dispatch)
	Process a key event and dispatch a TextAreaChangedMsg with the new document state.
void	Render (IRenderContext ctx)
	Renders visible lines into the allocated region.
	TextArea ()
	Object-initializer constructor; all properties default.
	TextArea (IReadOnlyList< string >? lines=null, int cursorRow=0, int cursorCol=0, int scrollRow=0, int maxLines=0, Style? style=null)
	Positional constructor for inline usage.

Static Public Member Functions
static int	ComputeScrollRow (int cursorRow, int viewportHeight, int currentScrollRow)
	Compute a new ScrollRow that keeps cursorRow within the visible viewport.

Properties
int	CursorCol [get]
	Zero-based column of the cursor within the current line.
int	CursorRow [get]
	Zero-based row of the cursor within Lines.
bool	HasFocus [get, set]
	True when this widget holds keyboard focus.
SizeConstraint	Height = SizeConstraint.Flex(1) [get]
	Height constraint used by the layout engine.
IReadOnlyList< string >	Lines = [""] [get]
	Lines of text. Never null; empty list = empty document.
int	MaxLines [get]
	Maximum number of lines allowed.
int	ScrollRow [get]
	First line index rendered.
Style	Style = Style.Default [get]
	Visual style for the text content. Inherits theme base style when unset.
SizeConstraint	Width = SizeConstraint.Flex(1) [get]
	Width constraint used by the layout engine.

Detailed Description

A multi-line text input widget.

Cursor position and scroll state live in the model (all properties are { get; init; }) — use the TextAreaChangedMsg returned from OnKeyEvent to derive the next widget state via with.

Scroll — The widget renders lines [ScrollRow, ScrollRow + visibleHeight). Update ScrollRow in your model's Update handler; use ComputeScrollRow as a helper.

Line endings — All text is stored as a list of strings (one per logical line). The widget does not produce or consume
in its messages.

Constructor & Destructor Documentation

TextArea()

ConsoleForge.Widgets.TextArea.TextArea	(	IReadOnlyList< string >?	lines = null,
		int	cursorRow = 0,
		int	cursorCol = 0,
		int	scrollRow = 0,
		int	maxLines = 0,
		Style?	style = null )

Positional constructor for inline usage.

Parameters

lines	Initial line content. Null or empty → single empty line.
cursorRow	Initial cursor row (clamped).
cursorCol	Initial cursor column (clamped).
scrollRow	Initial vertical scroll offset.
maxLines	Max line count (0 = unlimited).
style	Optional visual style override.

Member Function Documentation

ComputeScrollRow()

int ConsoleForge.Widgets.TextArea.ComputeScrollRow ( int cursorRow, int viewportHeight, int currentScrollRow )

static

Compute a new ScrollRow that keeps cursorRow within the visible viewport.

Call this from your model's Update handler when handling TextAreaChangedMsg and WindowResizeMsg.

Parameters

cursorRow	The cursor row after the edit.
viewportHeight	Number of visible rows in the TextArea's region.
currentScrollRow	Current scroll offset.

Returns

Adjusted scroll row ensuring cursor is visible.

OnKeyEvent()

void ConsoleForge.Widgets.TextArea.OnKeyEvent	(	KeyMsg	key,
		Action< IMsg >	dispatch )

Process a key event and dispatch a TextAreaChangedMsg with the new document state.

The model should replace this widget instance with one constructed from the message fields using with expressions.

Implements ConsoleForge.Layout.IFocusable.

Render()

void ConsoleForge.Widgets.TextArea.Render

(

IRenderContext

ctx

)

Renders visible lines into the allocated region.

Lines outside [ScrollRow, ScrollRow + height) are not drawn. When focused, the cursor position is highlighted with reverse-video.

Implements ConsoleForge.Layout.IWidget.

Property Documentation

MaxLines

int ConsoleForge.Widgets.TextArea.MaxLines

get

Maximum number of lines allowed.

0 = unlimited. When at the limit, Enter is a no-op.

ScrollRow

int ConsoleForge.Widgets.TextArea.ScrollRow

get

First line index rendered.

Used for vertical scrolling. Update via ComputeScrollRow when handling TextAreaChangedMsg.

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

• src/ConsoleForge/Widgets/TextArea.cs