Checkbox

The Checkbox widget displays a toggleable checked/unchecked/indeterminate state with an optional label.

Basic Usage

Create a checkbox with the Checkbox() extension method. Use OnToggled() to handle state changes.

csharp

using Hex1b;
using Hex1b.Widgets;

var state = new TermsState();

await using var terminal = Hex1bTerminal.CreateBuilder()
    .WithHex1bApp((app, options) => ctx => ctx.VStack(v => [
        v.Text("Terms and Conditions"),
        v.Text(""),
        v.Checkbox(state.AcceptTerms ? CheckboxValue.Checked : CheckboxValue.Unchecked)
            .Label("I accept the terms")
            .OnToggled(e => state.AcceptTerms = !state.AcceptTerms),
        v.Text(""),
        v.Button("Continue")
            .OnClick(_ => { if (state.AcceptTerms) Console.WriteLine("Accepted!"); })
    ]))
    .Build();

await terminal.RunAsync();

class TermsState
{
    public bool AcceptTerms { get; set; }
}

dotnet run

Key features:

• Click or press Space/Enter to toggle
• Use Label() to add descriptive text
• Manage state externally (checkboxes are stateless widgets)

States

Checkboxes support three visual states:

csharp

using Hex1b;
using Hex1b.Widgets;

await using var terminal = Hex1bTerminal.CreateBuilder()
    .WithHex1bApp((app, options) => ctx => ctx.VStack(v => [
        v.Text("Checkbox States:"),
        v.Text(""),
        v.Checkbox().Unchecked().Label("Unchecked ▢"),
        v.Checkbox().Checked().Label("Checked ▣"),
        v.Checkbox().Indeterminate().Label("Indeterminate ▤")
    ]))
    .Build();

await terminal.RunAsync();

dotnet run

State	Display	Usage
Unchecked	▢	Default, option not selected
Checked	▣	Option is selected
Indeterminate	▤	Partial selection (e.g., some children selected)

Fluent API

Method	Description
Checked()	Set to checked state
Unchecked()	Set to unchecked state
Indeterminate()	Set to indeterminate state
Label(string)	Add label text after the checkbox
OnToggled(handler)	Handle toggle events

Keyboard Support

Key	Action
Space	Toggle the checkbox
Enter	Toggle the checkbox
Tab	Move to next focusable widget

Related Widgets

• ToggleSwitch — On/off switch with visual feedback
• Tree — Hierarchical lists with multi-select checkboxes
• Button — Clickable actions