l_args

The property l_args->action can be open, swap, or close.

• • ’open Passed when a new window has been created, or when the user has called deOpen with an existing window. In the latter case, the Design Editor will remove the current contents of the window before installing the new design. Thus the new design always becomes the bottom level of the stack in the window. In the process of removing the current contents of the window, triggers for designs on its stack will be called and might necessitate interaction with the user. The data trigger should abort and return nil if the specified design cannot be opened. To install or stack a design in the window requires that the application create a context and link it to the window. The application trigger is responsible for all context creation and initialization.

• • ’swap Passed when the design is being replaced on the window stack by another design of the same view type. ’swap is equivalent to ’close on the current design followed by ’install on the new design, except that because the view type is not changing, the data trigger and app trigger need only be called once, and the context can be overwritten instead of destroyed and recreated.
  • ’close Passed when the design is being removed from the window stack. The data trigger can then close the design data.

g_handle

Identifier for the opened file.

nil

The operation failed and the process is aborted.