TextBoxState

Namespace: Hex1b.Widgets

Assembly: Hex1b.dll

Mutable state object for a . Owns the text buffer, the cursor position, the optional selection anchor, and the multiline / line limits configured through the widget.

public class TextBoxState

Inheritance

Object → TextBoxState

Constructors

TextBoxState()

Creates an empty text box state with the cursor at offset zero.

public TextBoxState()

TextBoxState(string)

Creates a text box state seeded with initialText. The cursor is positioned at the end of the supplied text and there is no active selection.

Parameters:

• initialText (String): The initial text to populate the buffer with. A null value is treated as an empty string.

public TextBoxState(string initialText)

Properties

CursorPosition

Returns: Int32

public int CursorPosition { get; set; }

HasSelection

Returns true if there is an active text selection.

Returns: Boolean

public bool HasSelection { get; }

IsMultiline

When true, the text box operates in multi-line mode. Enter inserts newlines, Up/Down navigate between lines, Home/End operate on the current line.

Returns: Boolean

public bool IsMultiline { get; set; }

MaxLines

Maximum number of lines allowed in multiline mode. When null, there is no limit.

Returns: Nullable<Int32>

public int? MaxLines { get; set; }

SelectedText

Gets the selected text.

Returns: String

public string SelectedText { get; }

SelectionAnchor

The anchor position for text selection. If null, no selection is active. Selection range is from min(SelectionAnchor, CursorPosition) to max(SelectionAnchor, CursorPosition).

Returns: Nullable<Int32>

public int? SelectionAnchor { get; set; }

SelectionEnd

Gets the end index of the selection (exclusive).

Returns: Int32

public int SelectionEnd { get; }

SelectionStart

Gets the start index of the selection (inclusive).

Returns: Int32

public int SelectionStart { get; }

Text

Returns: String

public string Text { get; set; }

Methods

ClearSelection()

Clears the current selection.

public void ClearSelection()

GetLineCount()

Returns the number of lines in the text (1-based; empty string has 1 line).

Returns: Int32

public int GetLineCount()

GetLineLength(int)

Returns the length of the given 0-based line (excluding the newline character).

Parameters:

• line (Int32):

Returns: Int32

public int GetLineLength(int line)

GetLineStartOffset(int)

Returns the flat offset where the given 0-based line starts. Line 0 starts at offset 0.

Parameters:

• line (Int32):

Returns: Int32

public int GetLineStartOffset(int line)

GetLineText(int)

Gets the text content of the given 0-based line (excluding newline).

Parameters:

• line (Int32):

Returns: String

public string GetLineText(int line)

HandleInput(Hex1bKeyEvent)

Handles keyboard input for the text box. Returns true if the input was handled, false if it should be passed to parent containers.

Parameters:

• evt (Hex1bKeyEvent):

Returns: Boolean

public bool HandleInput(Hex1bKeyEvent evt)

InsertNewline()

Inserts a newline at the current cursor position.

public void InsertNewline()

LineColumnToOffset(int, int)

Converts a (line, column) pair (both 0-based) to a flat cursor offset. Column is clamped to the line's length.

Parameters:

• line (Int32):
• column (Int32):

Returns: Int32

public int LineColumnToOffset(int line, int column)

MoveDown(bool)

Moves the cursor down one line, preserving the preferred column.

Parameters:

• extend (Boolean):

public void MoveDown(bool extend = false)

MoveUp(bool)

Moves the cursor up one line, preserving the preferred column.

Parameters:

• extend (Boolean):

public void MoveUp(bool extend = false)

OffsetToLineColumn(int)

Converts a flat cursor offset to a (line, column) pair (both 0-based).

Parameters:

• offset (Int32):

Returns: ValueTuple<Int32, Int32>

public (int line, int column) OffsetToLineColumn(int offset)

SelectAll()

Selects all text.

public void SelectAll()

Remarks

A can be created and managed inside a composite via and routed into a with . When state is supplied this way, the textbox becomes a pure view of the instance — the parent can mutate directly and the change is reflected on the next reconcile, without an OnTextChanged shadow-sync handler.

When the parent does not supply a state instance, the framework allocates one per node automatically and seeds it from the widget's constructor argument.