push

Temporarily redirects markup data to a sub-parser.

This function may only be called from the start_element handler of a `GtkBuildableParser`. It must be matched with a corresponding call to pop in the matching end_element handler (except in the case that the parser aborts due to an error).

All tags, text and other data between the matching tags is redirected to the subparser given by parser. user_data is used as the user_data for that parser. user_data is also passed to the error callback in the event that an error occurs. This includes errors that occur in subparsers of the subparser.

The end tag matching the start tag for which this call was made is handled by the previous parser (which is given its own user_data) which is why pop is provided to allow "one last access" to the user_data provided to this function. In the case of error, the user_data provided here is passed directly to the error callback of the subparser and pop should not be called. In either case, if user_data was allocated then it ought to be freed from both of these locations.

This function is not intended to be directly called by users interested in invoking subparsers. Instead, it is intended to be used by the subparsers themselves to implement a higher-level interface.

For an example of how to use this, see push which has the same kind of API.

Parameters:

this	a `GtkBuildableParseContext`
parser	a `GtkBuildableParser`
user_data	user data to pass to `GtkBuildableParser` functions