init(directInfo:size:callbacks:)
Creates a direct-access data provider.
Declaration
init?(directInfo info: UnsafeMutableRawPointer?, size: off_t, callbacks: UnsafePointer<CGDataProviderDirectCallbacks>)Parameters
- info:
A pointer to data of any type or
NULL. When Core Graphics calls the functions specified in thecallbacksparameter, it sends each of the functions this pointer. - size:
The number of bytes of data to provide.
- callbacks:
A pointer to a Cgdataproviderdirectcallbacks structure that specifies the callback functions you implement to handle the data provider’s basic memory management.
Return Value
A new data provider. In Objective-C, you’re responsible for releasing this object using CGDataProviderRelease.
Discussion
You use this function to create a direct-access data provider that uses callback functions to read data from your program in a single block.