Initializer

init(sequentialInfo:callbacks:)

Creates a sequential-access data provider.

Declaration

Parameters

info

A pointer to data of any type or NULL. When Core Graphics calls the functions specified in the callbacks parameter, it sends each of the functions this pointer.

callbacks

A pointer to a CGDataProviderSequentialCallbacks structure that specifies the callback functions you implement to handle the data provider’s basic memory management.

Return Value

A new data provider. You are responsible for releasing this object using CGDataProviderRelease.

Discussion

You use this function to create a sequential-access data provider that uses callback functions to read data from your program in a single block.

See Also

Creating Sequential-Access Data Providers

struct CGDataProviderSequentialCallbacks

Defines a structure containing pointers to client-defined callback functions that manage the sending of data for a sequential-access data provider.

typealias CGDataProviderRewindCallback

A callback function that moves the current position in the data stream back to the beginning.

typealias CGDataProviderGetBytesCallback

A callback function that copies from a provider data stream into a Core Graphics buffer.

typealias CGDataProviderSkipForwardCallback

A callback function that advances the current position in the data stream supplied by the provider.

typealias CGDataProviderReleaseInfoCallback

A callback function that releases any private data or resources associated with the data provider.