The state_change message is sent by myzPAX when the browser back/forward navigation is detected.
Message Type
type messageType = 'state_change';Payload
type Payload = {
state: string | null;
action: 'back' | 'forward';
};When It Is Sent
- On browser navigation events (popstate).
Example
addZpaxMessageListener('state_change', (message) => {
const { action, state } = message.data;
console.log(`User navigated ${action}. State:`, state);
syncWithHistoryState(state);
});Use Cases
- Manage SPA state across navigation.
- Detect if user left a flow.
Related
sendZpaxMessage('set_state', ...)— To set state.addZpaxMessageListener— Function used to subscribe to incoming messages.