The Messages app adds the message to the transcript as soon as the user taps the send button.
Use the following workflow to receive and update a message.
When the user taps on one of your MSMessage entries, the conversation’s selectedMessage property is changed to the tapped message. Use key-value observing to respond to these changes. Extract the current state from the message’s url property, and present it to the user.
For more information on receiving messages, see MSMessage.
After the user responds, create the following:
A new URL that encodes the updated message state. For example, you could encode the data as key-value pairs in the URL’s query string. For more information, see the MSMessage class’s url property.
A new layout object that describes the updated message’s appearance. For more information, see the MSMessage class’s layout property.
A string that describes the message’s current state. For more information, see the MSMessage class’s summaryText property.