Referans olarak belirtilen itemID öğesini kullanan bir öğe penceresini getirir. Bu yöntem, genellikle bir gönderen isteğinden kaynaklanan daha fazla sıra öğesine ihtiyaç duyduğunda MediaManager tarafından çağrılır. nextCount veya prevCount ayarlandıysa fetchItems yalnızca referans öğeden sonraki veya referans öğeden önceki öğeleri döndürür. Hem nextCount hem de prevCount ayarlanırsa itemId içeren
bir öğe penceresi döndürülür.
Sırayı requestData ile başlatır. Alıcı yeni bir cast.framework.messages.Command.LOAD isteği aldığında
aranır. Bu işlem null değerine döner veya çözümlenirse varsayılan sıra oluşturma uygulaması, queueData.items veya LOAD istek verilerindeki tek medya öğesine dayalı bir sıra oluşturur.
Geçerli öğeyi itemId olarak ayarlar. Şu anda oynatılan öğeyi değiştirdiğinde MediaManager tarafından çağrıldı.
Parametre
itemId
sayı
Öğenin benzersiz kimliğidir.
onItemsInserted
onItemsInserted(items, insertBefore)
Bu oturumda alıcı sırasına aşağıdaki öğelerin eklendiğini belirten bir geri çağırma. Bulut tabanlı bir uygulama, sırasını bu yeni bilgilere göre güncelleyebilir.
Eklenen listeden hemen sonra bulunan
öğenin kimliği. Kimlik sağlanmazsa eklenen liste sıranın sonuna eklenir.
onItemsRemoved
onItemsRemoved(itemIds)
Aşağıdaki öğelerin bu oturumda alıcı sırasından kaldırıldığını belirten bir geri çağırma. Bulut tabanlı bir uygulama, sırasını bu yeni bilgilere göre güncelleyebilir.
Parametre
itemIds
Sayı dizisi
Kaldırılan öğelerin kimlikleri.
Değer boş olamaz.
onItemsReordered
onItemsReordered(items, insertBefore)
Aşağıdaki öğelerin yeniden sıralandığını belirten bir geri çağırma.
[null,null,["Son güncelleme tarihi: 2025-07-25 UTC."],[[["\u003cp\u003e\u003ccode\u003eQueueBase\u003c/code\u003e provides a foundational structure for managing media queues within the Cast framework.\u003c/p\u003e\n"],["\u003cp\u003eIt offers methods to initialize, fetch, and manipulate queue items, including shuffling and unshuffling.\u003c/p\u003e\n"],["\u003cp\u003eDevelopers can extend this base class to implement custom queueing logic for their Cast receiver applications.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eQueueBase\u003c/code\u003e interacts with \u003ccode\u003eMediaManager\u003c/code\u003e to handle queue updates and playback transitions.\u003c/p\u003e\n"],["\u003cp\u003eCallbacks are provided to inform developers about queue modifications like insertions, removals, and reordering.\u003c/p\u003e\n"]]],["The `QueueBase` class manages a media queue, fetching, initializing, and modifying items. Key actions include `fetchItems` to retrieve a range of items based on a reference ID, `initialize` to set up the queue upon a load request, and `nextItems`/`prevItems` to get items following or preceding a given item. Other methods handle updates like `onItemsInserted`, `onItemsRemoved`, `onItemsReordered`, and also manage playback order using `shuffle` and `unshuffle`. The `onCurrentItemIdChanged` method is called when an item is playing.\n"],null,["# Class: QueueBase\n\ncast.[framework](/cast/docs/reference/web_receiver/cast.framework).QueueBase\n============================================================================\n\nclass static\n\nBase implementation of a queue.\n\nConstructor\n-----------\n\n### QueueBase\n\nnew\nQueueBase()\n\nMethods\n-------\n\n### fetchItems\n\nfetchItems(itemId, nextCount, prevCount) returns (non-null Array of non-null [cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem) or non-null Promise containing non-null Array of non-null [cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem))\n\nFetches a window of items using the specified `itemID` as reference. This\nmethod is called by `MediaManager` when it needs more queue items, often\nstemming from a sender request. If either `nextCount` or `prevCount` are\nset, `fetchItems` will only return items after or before the reference\nitem. If both `nextCount` and `prevCount` are set, a window of items\nincluding `itemId` will be returned.\n\n| #### Parameter ||\n|-----------|---------------------------------------------------|\n| itemId | number The ID of the reference item. |\n| nextCount | number Number of items after the reference item. |\n| prevCount | number Number of items before the reference item. |\n\nReturns\n\n: `(non-null Array of non-null `[cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem)` or non-null Promise containing non-null Array of non-null `[cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem)`)`\n\n### initialize\n\ninitialize(requestData) returns ([cast.framework.messages.QueueData](/cast/docs/reference/web_receiver/cast.framework.messages.QueueData) or non-null Promise containing nullable [cast.framework.messages.QueueData](/cast/docs/reference/web_receiver/cast.framework.messages.QueueData))\n\nInitializes the queue with `requestData`. Called when the receiver\ngets a new `cast.framework.messages.Command.LOAD` request. If this returns or\nresolves to `null`, the default queueing implementation will create a queue\nbased on `queueData.items` or on the single media item in the `LOAD`\nrequest data.\n\n| #### Parameter ||\n|-------------|----------------------------------------------------------------------------------------------------------------------------------------------|\n| requestData | [cast.framework.messages.LoadRequestData](/cast/docs/reference/web_receiver/cast.framework.messages.LoadRequestData) Value must not be null. |\n\nReturns\n\n: `(nullable `[cast.framework.messages.QueueData](/cast/docs/reference/web_receiver/cast.framework.messages.QueueData)` or non-null Promise containing nullable `[cast.framework.messages.QueueData](/cast/docs/reference/web_receiver/cast.framework.messages.QueueData)`)`\n\n### nextItems\n\nnextItems(itemId) returns (nullable Array of non-null [cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem) or non-null Promise containing nullable Array of non-null [cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem))\n\nReturns all items in the queue following `itemID`. This is called by\n`MediaManager`.\n\n| #### Parameter ||\n|--------|-----------------------------------------------|\n| itemId | Optional number The ID of the reference item. |\n\nReturns\n\n: `(nullable Array of non-null `[cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem)` or non-null Promise containing nullable Array of non-null `[cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem)`)`\n\n### onCurrentItemIdChanged\n\nonCurrentItemIdChanged(itemId)\n\nSets the current item to `itemId`. Called by `MediaManager`\nwhen it changes the currently-playing item.\n\n| #### Parameter ||\n|--------|------------------------------------|\n| itemId | number The unique ID for the item. |\n\n### onItemsInserted\n\nonItemsInserted(items, insertBefore)\n\nA callback that indicates that the following items have been inserted into\nthe receiver queue in this session. A cloud-based implementation might\nupdate its queue based on this new information.\n\n| #### Parameter ||\n|--------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| items | Array of non-null [cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem) The items that were inserted. Value must not be null. |\n| insertBefore | Optional number ID of the item that was located immediately after the inserted list. If the ID is not provided, the inserted list was appended to the end of the queue. |\n\n### onItemsRemoved\n\nonItemsRemoved(itemIds)\n\nA callback that indicates that the following items have been removed from\nthe receiver queue in this session. A cloud-based implementation might\nupdate its queue based on this new information.\n\n| #### Parameter ||\n|---------|---------------------------------------------------------------------------------|\n| itemIds | Array of number The IDs of the items that were removed. Value must not be null. |\n\n### onItemsReordered\n\nonItemsReordered(items, insertBefore)\n\nA callback that indicates that the following items have been reordered.\n\n| #### Parameter ||\n|--------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| items | Array of non-null [cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem) The IDs of the items that were reordered. Value must not be null. |\n| insertBefore | Optional number ID of the item that is located immediately after the reordered list. If `insertBefore` is not provided, the reordered list will be appended to the end of the queue. |\n\nSee also\n: [cast.framework.messages.QueueReorderRequestData#itemIds](/cast/docs/reference/web_receiver/cast.framework.messages.QueueReorderRequestData#itemIds) for more details.\n\n### prevItems\n\nprevItems(itemId) returns (nullable Array of non-null [cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem) or non-null Promise containing nullable Array of non-null [cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem))\n\nReturns all items before `itemID`. This is called by `MediaManager`.\n\n| #### Parameter ||\n|--------|-----------------------------------------------|\n| itemId | Optional number The ID of the reference item. |\n\nReturns\n\n: `(nullable Array of non-null `[cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem)` or non-null Promise containing nullable Array of non-null `[cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem)`)`\n\n### shuffle\n\nshuffle() returns (nullable Array of non-null [cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem) or non-null Promise containing nullable Array of non-null [cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem))\n\nShuffles the queue and returns new queue items. Returns `null` if the\noperation is not supported.\n\nReturns\n\n: `(nullable Array of non-null `[cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem)` or non-null Promise containing nullable Array of non-null `[cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem)`)`\n\n### unshuffle\n\nunshuffle() returns (nullable Array of non-null [cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem) or non-null Promise containing nullable Array of non-null [cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem))\n\nUnshuffles the queue and returns new queue items. Returns `null` if the\noperation is not supported.\n\nReturns\n\n: `(nullable Array of non-null `[cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem)` or non-null Promise containing nullable Array of non-null `[cast.framework.messages.QueueItem](/cast/docs/reference/web_receiver/cast.framework.messages.QueueItem)`)`"]]
