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While all of these options are always available, the options are condensed to those unique actions and presented to the connected client in a number of ways. In other words, when the queue is empty, the only presented option is Now because there is nothing to modify. Sending Replace in such a scenario would perform the same exact action as Now. The list of options is communicated to the connected client via the LocalQueueOptions status event or as a menu when indicating playback via the ClarifyTitleIntent command.
The intended option is communicated to the server by appending it to the end of the Play<Container> command after the container’s GUID. For example, PlayAlbum c8507e3c-a5c0-4503-bd87-0b711580987e Replace. For items where a listAction is provided and that listAction is ClarifyTitleIntent, append the verb to the end of that command. For example, ClarifyTitleIntent 1609d2f0-b7c8-4996-9a48-4f434ad436e0 Next. Leaving the verb off will result in a menu for the user to select from unless there is only one action available, in which case MMS will perform that action.
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