canGoBack

Control whether users can leave a jig, with an optional confirmation modal.

Use canGoBack on a jig to control whether users can leave the current screen.

It applies to all user-initiated back navigation from that jig, including:

• Android hardware back
• iOS swipe-back
• The header back button
• action.go-back and action.go-to triggered from the jig

Where to use it

Configure canGoBack on any jig type.

Use it when you need to:

• confirm before leaving a read-only screen
• protect unsaved changes across multiple components
• block navigation in kiosk-style flows

How it works

canGoBack has a required when condition and an optional confirm modal.

It resolves in three ways:

• when is true — navigation proceeds
• when is false and confirm is set — a modal opens
• when is false and confirm is not set — navigation is blocked

Configuration options

Property	Type	Description
when	boolean or Expression	Controls whether the user can leave the jig.
confirm	object	Optional modal shown when when resolves to false.
confirm.title	string or Expression	Modal title.
confirm.description	string or Expression	Modal body text.
confirm.confirm	string or Expression	Confirm button label.
confirm.cancel	string or Expression	Cancel button label.
confirm.style.isDanger	boolean	Styles the confirm button as a destructive action.

Use canGoBack when the whole jig owns the navigation rule. Use component.form when you only need the form discard alert.

Considerations

• It does not run in widgets, previews, or nested jig content.
• In jig.tabs, an inactive tab can still block leaving the screen.
• If a form still uses isDiscardChangesAlertEnabled: true, the form discard alert still applies.
• Use a hard block carefully. It prevents all supported back navigation from that jig.

Examples

Confirm before leaving

This example blocks navigation when the jig is dirty and asks the user to confirm.

title: Edit notes
type: jig.default

canGoBack:
  when: =$not(@ctx.jig.state.dirty)
  confirm:
    title: Discard unsaved changes?
    description: Your notes will be lost.
    confirm: Discard
    cancel: Keep editing
    style:
      isDanger: true

Hard block navigation

This example prevents leaving the jig with no modal.

title: Check-in kiosk
type: jig.default

canGoBack:
  when: false

Use a form's dirty state

This example moves the back-navigation rule to the jig level and uses the form state in the condition.

title: Profile
type: jig.default

canGoBack:
  when: =@ctx.components.profile-form.state.isDirty
  confirm:
    title: Leave this form?
    description: Your changes have not been saved.
    confirm: Leave
    cancel: Stay

children:
  - type: component.form
    instanceId: profile-form
    options:
      isDiscardChangesAlertEnabled: false
      children:
        - type: component.text-field
          instanceId: first-name
          options:
            label: First name

action.go-back uses the same rule

This example shows a back action inside the jig. The same canGoBack rule still applies, even when the action button is tapped.

title: Edit notes
type: jig.default

canGoBack:
  when: =$not(@ctx.jig.state.dirty)
  confirm:
    title: Discard unsaved changes?
    description: Your notes will be lost.
    confirm: Discard
    cancel: Keep editing

actions:
  - children:
      - type: action.go-back
        options:
          title: Go back

Related topics

• confirm
• go-back
• form