init(formatIdentifier:formatVersion:data:)
Initializes an adjustment object with the specified format and data.
Declaration
init(formatIdentifier: String, formatVersion: String, data: Data)Parameters
- formatIdentifier:
A string that uniquely identifies the format of the adjustment data.
- formatVersion:
A version number for the adjustment data format.
- data:
A serialized form of whatever information is needed to reconstruct the adjustment.
Return Value
An initialized adjustment object.
Discussion
To uniquely identify the adjustments your app makes, use the formatIdentifier and formatVersion parameters. These parameters help you determine whether and how to interpret the adjustment data when working with an edited asset later. For best results, use reverse-DNS-style identifiers and monotonically increasing version numbers.
For example, in the first version of your app, you might save adjustment data using the identifier com.example.myApp and version 1.0. If a later version of your app adds incompatible information to the adjustment data, you can use the same identifier and increase the version number to 2.0.
Use the data parameter to store whatever information is useful to your app for reconstructing an edit. For example, if your app applies Core Image filters to photos, you can use this parameter to store a serialized property list that describes the filters and their parameters.
Your app must provide a non-empty NSData object for the data parameter. If you cannot provide relevant data to describe an edit, you may pass data that encodes an NSUUID object.