stepper-command-dialog

name	stepper-command-dialog
description	Step-by-step guidance for building a multi-step wizard dialog (StepperCommandDialog) in a Cratis Arc application. Use whenever a command requires gathering information across multiple steps, implementing a wizard flow, breaking a complex form into named stages, or using StepperCommandDialog, StepperPanel, validateOnInit, or wizard-style navigation.

StepperCommandDialog — Wizard Dialogs

StepperCommandDialog organizes a single command form across multiple named steps. Users navigate with Previous and Next buttons; Submit only appears on the last step when every field across all steps is valid.

Use this instead of CommandDialog when:

• The form has too many fields to show at once
• Fields can be grouped into logical stages (e.g. "Contact Info → Project Details → Summary")
• You want guided, linear input with per-step validation feedback
• The operation feels like a wizard or an onboarding flow

---

Step 1 — Define the command

A single command collects all fields across all steps. Each step contributes properties to the same command instance.

// Projects/CreateProject/CreateProject.cs — the slice file
[Command]
public record CreateProject(ProjectName Name, EmailAddress Email, Description Description, Money Budget)
{
    public ProjectCreated Handle() => new(Name, Email, Description, Budget);
}

Run a Release dotnet build to generate the CreateProject TypeScript proxy before importing it.

---

Step 2 — Build the dialog component

import { StepperCommandDialog } from '@cratis/components/CommandDialog';
import { StepperPanel } from 'primereact/stepperpanel';
import { InputTextField, TextAreaField, NumberField } from '@cratis/components/CommandForm/fields';
import { DialogResult, useDialogContext } from '@cratis/arc.react/dialogs';
import { CreateProject } from '../api/Projects/CreateProject';

const CreateProjectDialog = () => {
    const { closeDialog } = useDialogContext();

    return (
        <StepperCommandDialog<CreateProject>
            command={CreateProject}
            title="Create New Project"
            okLabel="Create"
            onConfirm={() => closeDialog(DialogResult.Ok)}
            onCancel={() => closeDialog(DialogResult.Cancelled)}
        >
            <StepperPanel header="Contact Info">
                <InputTextField<CreateProject>
                    value={c => c.email}
                    title="Contact Email"
                    placeholder="Enter contact email"
                    type="email"
                />
            </StepperPanel>
            <StepperPanel header="Project Details">
                <InputTextField<CreateProject>
                    value={c => c.name}
                    title="Project Name"
                    placeholder="Enter project name"
                />
                <TextAreaField<CreateProject>
                    value={c => c.description}
                    title="Description"
                    placeholder="Describe the project"
                    rows={4}
                />
            </StepperPanel>
            <StepperPanel header="Budget">
                <NumberField<CreateProject>
                    value={c => c.budget}
                    title="Budget"
                    placeholder="Enter budget"
                />
            </StepperPanel>
        </StepperCommandDialog>
    );
};

Rules:

• Each StepperPanel takes a header string — this is the step label shown in the wizard navigation bar
• All CommandForm fields inside any StepperPanel are bound to the same command instance
• Fields map to command properties via the value={c => c.propertyName} accessor
• The Next button is disabled while the current step has validation errors
• Submit only appears on the last step when all fields (across all steps) are valid

---

Step 3 — Wire the dialog to a parent component

import { useDialog } from '@cratis/arc.react/dialogs';
import { Button } from 'primereact/button';

export const ProjectsPage = () => {
    const [CreateProjectDialogWrapper, showCreateProject] = useDialog(CreateProjectDialog);

    return (
        <>
            <Button label="New Project" onClick={() => showCreateProject()} />
            <CreateProjectDialogWrapper />
        </>
    );
};

Use the PrimeReact Button (or a Cratis Components wrapper) — never a raw <button className="p-button">.

---

Navigation behavior

Step	Footer buttons shown
First step	Next
Middle step	Previous, Next
Last step (any step invalid)	Previous
Last step (all valid)	Previous, Submit

Cancel is always available via the × button in the dialog header.

---

Validation indicators

Step number circles in the wizard navigation bar change color to reflect validity:

• Red circle — the step contains at least one field with a validation error
• Green circle — the step has been visited (navigated through) and all its fields are valid
• Default color — the step has not been visited yet
• Dimmed — a step that is not the currently active step

To trigger validation immediately on open (before the user types anything), pass validateOnInit:

<StepperCommandDialog
    command={CreateProject}
    validateOnInit
    ...
>

This is useful when the dialog opens with pre-populated values that may already be invalid.

---

Customizing step labels

The okLabel, nextLabel, and previousLabel props override the default button text:

<StepperCommandDialog
    command={CreateProject}
    title="Register Employee"
    okLabel="Register"
    nextLabel="Continue →"
    previousLabel="← Back"
    ...
>

---

Pre-populating values (edit wizard)

Use currentValues for fields the user can change and initialValues for hidden/fixed fields (e.g. an ID):

<StepperCommandDialog
    command={UpdateProject}
    currentValues={{ name: project.name, description: project.description }}
    initialValues={{ projectId: project.id }}
    ...
>

---

Stepper orientation

For longer wizards, vertical orientation can be more readable:

<StepperCommandDialog orientation="vertical" ...>
    <StepperPanel header="Step One"> ... </StepperPanel>
    <StepperPanel header="Step Two"> ... </StepperPanel>
</StepperCommandDialog>

---

Props reference

Prop	Type	Default	Description
command	Constructor<TCommand>	—	Required. Command class constructor
title	string	—	Required. Dialog header title
children	StepperPanel[]	—	Required. Wizard steps
okLabel	string	'Submit'	Submit button label (last step)
nextLabel	string	'Next'	Next button label
previousLabel	string	'Previous'	Previous button label
visible	boolean	true	Controls dialog visibility
width	string	'600px'	Dialog width
isValid	boolean	—	Extra validity gate combined with form validity
validateOnInit	boolean	—	Run validation on mount to show errors immediately
orientation	'horizontal' | 'vertical'	'horizontal'	Stepper layout direction
linear	boolean	true	Require steps to be completed in order
initialValues	Partial<TCommand>	—	Fixed initial values (not shown to user as editable)
currentValues	Partial<TCommand>	—	Pre-populated editable values
onConfirm	() => void | Promise<void>	—	Called after successful execute
onCancel	() => void | Promise<void>	—	Called when user dismisses dialog
onBeforeExecute	(values: TCommand) => TCommand	—	Transform values before execution
pt	StepperProps['pt']	—	PrimeReact PassThrough for deep DOM customization

---

Common mistakes

Mistake	Fix
Putting a Cancel button in the footer	Don't — the × in the dialog header is the cancel action
One step per field	Group related fields; aim for 2–5 fields per step
Fields from different steps sharing the same value accessor	Each property should appear on exactly one step
Forgetting header on StepperPanel	Always set header — it is the navigation label
Using CommandDialog for a 4+ field form	Consider StepperCommandDialog to reduce cognitive load