observeWithNextSignal

fun observeWithNextSignal(eventHandler: (List<DittoDocument>, DittoLiveQueryEvent, DittoSignalNext) -> Unit): DittoLiveQuery

Enables you to listen for changes that occur on a collection, and to signal when you are ready for the live query to deliver the next event. The eventHandler closure will be called when local or remote changes are made to documents that match the query generated by the chain of operations that precedes the call to observeWithNextSignal. The returned DittoLiveQuery object must be kept in scope for as long as you want the provided eventHandler to be called when an update occurs.

Return

a DittoLiveQuery object that must be kept in scope for as long as you want to keep receiving updates.

Parameters

eventHandler

a closure that will be called every time there is a transaction committed to the store that involves modifications to documents matching the query in the collection that observe was called on.

Enables you to listen for changes that occur on a collection, and to signal when you are ready for the live query to deliver the next event. The eventHandler closure will be called when local or remote changes are made to documents that match the query generated by the chain of operations that precedes the call to observeWithNextSignal or observeLocalWithNextSignal. The returned DittoLiveQuery object must be kept in scope for as long as you want the provided eventHandler to be called when an update occurs.

Return

a DittoLiveQuery object that must be kept in scope for as long as you want to keep receiving updates.

Parameters

callback

an object that implements the DittoLiveQueryWithNextSignalCallback interface, whose update function will be called every time there is a transaction committed to the store that involves modifications to documents matching the query in the collection that observe was called on.