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Adopting Uniform Type Identifiers采用统一类型标识符
Introduction to Uniform Type Identifiers Overview 统一类型标示符概述
Declaring New Uniform Type Identifiers声明新的统一类型标示符
From the documentation:
If your application uses proprietary data formats, you should declare them in the Info.plist file of your application bundle. Some guidelines:
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Your UTI string must be unique. Following the reverse-DNS format beginning with com.companyName is a simple way to ensure uniqueness. While the system can support different UTI strings with the same specification, the reverse is not true.
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If your code relies on third-party UTI types that may not be present on the system, you should declare those UTIs as imported types in your bundle.
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Be sure to add conformance information if your proprietary type is a subtype of one or more existing types. In most cases you should not specify conformance to a nonpublic type, unless you are also declaring that type in your bundle. For a list of public and Apple-defined UTIs, see "System-Declared Uniform Type Identifiers"
如果你的应用程序用到专用的数据类型，你需要声明他们在你的应用程序绑定的info.plist文件。
一些提示：
你定义的统一类型标识 必须是特定的，随着com.companyName反向DNS格式开始是一个简单的方法，以确保其唯一性。虽然该系统可以支持不同的UTI的字符串按照同样的规格，反之则不行。
如果你的代码依赖第三方的UTI但是可能不存在于系统中，你应该声明UTI为绑定的导入类型
如果您的专有类型是一个或多个现有类型的一个子型，则必须要添加一致性的信息，在大多数情况下，你不应该为非公有制类型指定一致性，除非你也声明了此种类型在你的bundle中。
对于公众和苹果定义的UTI的列表，请参见“System-Declared Uniform Type Identifiers”