The Be Book - Special Topics - System Messages
The scripting system defines four generic messages that can operate on the specific properties of an object and two meta-messages that query an object about the messages it can handle. See "Scripting" in The Application Kit chapter for a full explanation.
This message requests the number of properties supported by the receiver. It contains no data, but the reply message should contain one field:
| Field | Type code | Description |
|---|---|---|
result | B_INT32_TYPE | The number of properties supported. |
This message requests the names of all message suites that the receiver supports. It doesn't contain any data, but the message that's sent in reply has one field:
| Field | Type code | Description |
|---|---|---|
suites | B_STRING_TYPE | An array of suite names. |
A suite is a named set of messages and specifiers. A
BHandler supports
the suite if it can respond to the messages and resolve the specifiers.
These messages—as their names state—target a particular property under the control of the target handler. They have the following data fields:
| Field | Type code | Description |
|---|---|---|
specifiers | B_MESSAGE_TYPE | An array of one or more
BMessages
that specify the targeted property. See
AddSpecifier()
in the BMessage class
of the Application Kit for details on the contents of a specifier. |
data | variable | For B_SET_PROPERTY messages only, the data that should be
set. The data type depends on the targeted property. |
