ContentProvider官方教程(6)provider支持的数据类型

Provider Data Types

　　Content providers can offer many different data types. The User Dictionary Provider offers only text, but providers can also offer the following formats:

• integer
• long integer (long)
• floating point
• long floating point (double)

　　Another data type that providers often use is Binary Large OBject (BLOB) implemented as a 64KB byte array. You can see the available data types by looking at the Cursor class "get" methods.

　　The data type for each column in a provider is usually listed in its documentation. The data types for the User Dictionary Provider are listed in the reference documentation for its contract class UserDictionary.Words (contract classes are described in the section Contract Classes). You can also determine the data type by calling Cursor.getType().

　　Providers also maintain MIME data type information for each content URI they define. You can use the MIME type information to find out if your application can handle data that the provider offers, or to choose a type of handling based on the MIME type. You usually need the MIME type when you are working with a provider that contains complex data structures or files. For example, the ContactsContract.Data table in the Contacts Provider uses MIME types to label the type of contact data stored in each row. To get the MIME type corresponding to a content URI, call ContentResolver.getType().

　　The section MIME Type Reference describes the syntax of both standard and custom MIME types.