on

Registers a listener for a Messenger event.

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Function

const unsubscribe = messenger.on(event, callback)

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Parameters

Parameter	type	required	description
event	String	Yes	Name of the event. One of the events below.
callback	Function	Yes	Called with the event's payload each time the event fires.

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Available events

Event	description
ready	Fires when initialize connects the Messenger.
transaction_complete	Fires when processWalletTransaction processes a payment, including a declined one. The payload has the Transaction. Check its status.
transaction_error	Fires when Pay Theory's servers return an error for processWalletTransaction. The payload has the error message. Errors the Messenger catches before it sends the payment, such as a missing field, only come back in the ERROR response.
iframe_unloaded	Fires when the Messenger's hidden iframe unloads.

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Returns

Returns a function that removes the event listener when called.

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Usage

// Register event listener
const unsubscribe = messenger.on('transaction_complete', (data) => {
  console.log('Transaction completed:', data.transaction);
});

// Remove event listener later
unsubscribe();

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Event data

ready event

{
  success: Boolean
}

transaction_complete event

{
  transaction: {
    transaction_id: String,
    status: String,
    gross_amount: Number,
    // ...the rest of the Transaction fields
  }
}

transaction_error event

{
  error: String
}

iframe_unloaded event

{
  timestamp: Number
}