Input

#include <Input.hpp>

Inherits: Widget

A text input widget for user text entry.

Input provides a text field where users can type, edit, and submit text. It supports standard keyboard editing (arrow keys, backspace, delete, etc.) and displays a placeholder when empty.

Features:

Text editing with cursor
Placeholder text when empty
onChange callback when text changes
onSubmit callback when user presses Enter
Horizontal scrolling for long text

Example Usage:

auto input = std::make_shared<Input>("Enter name...");
input->setOnChange([](/api/const std::string &text) {
  std::cout << "User typing: " << text << "\n";
});
input->setOnSubmit([](/api/const std::string &text) {
  std::cout << "User submitted: " << text << "\n";
});

Public Methods

Return	Name	Description
	`Input` `inline` `explicit`	Creates an input field with optional placeholder text.
`void`	`setText` `inline`	Sets the input field’s text. Moves the cursor to the end of the text.
`const std::string &`	`getText` `const` `inline`	Gets the current text in the input field.
`void`	`setPlaceholder` `inline`	Sets the placeholder text shown when the input is empty.
`void`	`setOnChange` `inline`	Sets the callback invoked when text changes. Called after each character insertion or deletion.
`void`	`setOnSubmit` `inline`	Sets the callback invoked when user presses Enter. Typically used to submit or confirm the input.
`bool`	`isFocusable` `virtual` `const` `inline`	Returns whether this widget can receive keyboard focus.
`core::Size`	`measure` `virtual`	Measures how much space this widget needs.
`bool`	`onEvent` `virtual`	Handles an input event.

Input

inline explicit

inline explicit Input(const std::string & placeholder)

Creates an input field with optional placeholder text.

Parameters

placeholder The text to show when input is empty (default: empty)

setText

inline

inline void setText(const std::string & t)

Sets the input field’s text. Moves the cursor to the end of the text.

Parameters

t The text to set

getText

const inline

inline const std::string & getText() const

Gets the current text in the input field.

Returns

The current text

setPlaceholder

inline

inline void setPlaceholder(const std::string & p)

Sets the placeholder text shown when the input is empty.

Parameters

p The placeholder text

setOnChange

inline

inline void setOnChange(std::function< void(const std::string &)> cb)

Sets the callback invoked when text changes. Called after each character insertion or deletion.

Parameters

cb Function receiving the current text (can be empty)

setOnSubmit

inline

inline void setOnSubmit(std::function< void(const std::string &)> cb)

Sets the callback invoked when user presses Enter. Typically used to submit or confirm the input.

Parameters

cb Function receiving the final text (can be empty)

isFocusable

virtual const inline

virtual inline bool isFocusable() const

Returns whether this widget can receive keyboard focus.

Widgets like Button and Input return true; containers return false.

Returns

True if this widget can be focused, false otherwise

measure

virtual

virtual core::Size measure(int availW, int availH)

Measures how much space this widget needs.

Called during the measurement pass to determine widget size requirements. Should return the preferred size based on available space.

Parameters

availW Maximum available width (may be ignored by widget)
availH Maximum available height (may be ignored by widget)

Returns

The Size this widget wants, or needs at minimum

onEvent

virtual

virtual bool onEvent(const core::events::Event & event)

Handles an input event.

Called by the framework to deliver an event to this widget. The default implementation runs any listeners registered via addEventListener(), then returns false. Subclasses (Button, Input, etc.) override this to add built-in behavior, and should call Widget::onEvent(event) first to give user listeners a chance to handle the event before the widget’s own logic.

Return true if the event was handled, false to let it bubble to the parent widget.

Parameters

event The input event

Returns

True if this widget (or one of its listeners) handled the event

Protected Methods

Return	Name	Description
`void`	`drawContent` `virtual`	Draws this widget’s content.

drawContent

virtual

virtual void drawContent(backend::Buffer & buf, core::Rect inner)

Draws this widget’s content.

Called by render() after background and borders are drawn. This is where you should draw your widget’s actual content. The inner rectangle accounts for borders and padding.

Parameters

buf The buffer to draw to
inner The inner rectangle (excluding border/padding)

Private Attributes

Return	Name	Description
`std::string`	`text`
`std::string`	`placeholder`
`int`	`cursor`
`int`	`scroll`
`std::function< void(const std::string &)>`	`onChange`
`std::function< void(const std::string &)>`	`onSubmit`

text

std::string text

placeholder

std::string placeholder

cursor

int cursor = 0

scroll

int scroll = 0

onChange

std::function< void(const std::string &)> onChange

onSubmit

std::function< void(const std::string &)> onSubmit

Private Methods

Return	Name	Description
`void`	`insertChar`
`void`	`deleteBack`
`void`	`deleteForward`
`void`	`moveCursor`
`void`	`updateScroll`

insertChar

void insertChar(char c)

deleteBack

void deleteBack()

deleteForward

void deleteForward()

moveCursor

void moveCursor(int delta)

updateScroll

void updateScroll()