[ CCode ( type_id = "shumate_data_source_request_get_type ()" ) ] [ Version ( since = "1.1" ) ] publicclassDataSourceRequest : Object
Represents a request to a [class@DataSource] for a tile.
Data sources can return a tile multiple times. For example, a [class@TileDownloader] may return cached data first, then later return data from
a network service when it arrives. This allows the map to be rendered as quickly as possible without waiting for the network unnecessarily.
Conventional async/finish method pairs don't support multiple returns. Instead, [method@DataSource.start_request] is available, which returns a
[class@DataSourceRequest] whose properties, [property@DataSourceRequest:data] and [property@DataSourceRequest:error], update as data becomes
available. The [signal@GObject.Object:ShumateDataSourceRequest:notify] signal can be used to watch for these changes. When the
request is done and no more data will be returned, [property@DataSourceRequest:completed] is set to true.
[class@DataSource] implementations can use a subclass of [class@DataSourceRequest], but the base class should be sufficient in most cases.