Finds the appropriate screen or container for a CAPI object.
capi
convert-to-screen &optional object => result
| object⇩ | 
A CAPI object, a plist, or keyword or  nil. | 
| result⇩ | 
A screen or a document-container. | 
The function convert-to-screen finds the appropriate screen or document container for the CAPI object object.
If object is nil, result is the default screen. object defaults to nil.
If object is a pane inside a MDI interface, then result is the document-container in the capi:container slot of the MDI interface, rather than the real screen, because this is more useful in most cases. To obtain the real screen, call convert-to-screen on the top level interface. See document-frame for a description of MDI interfaces.
object can be a keyword representing the CAPI library. This is equivalent to using the :library key in the plist case below. object can also be the special keyword :if-any, which finds a screen if there is any active screen, otherwise it returns nil.
object can be a plist. The keys below are supported on GTK+ and Motif. Other libraries ignore them.
| :display | 
The value is an X Window System display string describing the X display and screen to use. The default value is derived from the  DISPLAYenvironment variable or (on Motif) the-displaycommand-line option, or (on GTK+) the--displaycommand-line option. If neither is supplied, the default is to use the default screen on the local host. | 
| :host | 
The name of the host to use for the X Window System display. This key is valid only if no  :displaykey/value is supplied. The default value is the local host. | 
| :server-number | 
The number of the display server to use for the X Window System display. This key is valid only if no  :displaykey/value is supplied. The default value is 0. | 
| :screen-number | 
The number of the screen to use for the X Window System display. This key is valid only if no  :displaykey/value is supplied. The default value is the default screen of the display. | 
| :application-class | 
The value is a string naming the application class used for X Window System resources. The default value is "Lispworks". When running a delivered LispWorks image, you should specify the  
On GTK+ the value is used for constructing the default widget-name for top-level interfaces. The application-class is prepended to the interface name followed by a ".", so if application-class is  See element for the description of widget-name. 
Example GTK+ resource files are in  | 
| :fallback-resources | |
| 
On GTK+ the fallback resources are global, so they cannot be used to define different resources for different screens. Each call to  
On Motif the value is a list of strings representing the set of application context fallback resources to use (see  | |
| :library | 
The value specifies the CAPI library. This is useful on Linux, FreeBSD and x86/x64 Solaris platforms, and in the macOS/GTK+ image, to choose between  :gtkand:motifif the deprecated "capi-motif" module is loaded. | 
This keys is supported on Motif only. Other libraries ignore it.
| :command-line-args | 
The value is a list of strings representing the set of command-line arguments to pass to  | 
The resources are used only when no other system resource files can be found. When running a non-delivered LispWorks image, the default value of the :fallback-resources key is read from the file whose name is the value of the :application-class key in the app-defaults directory of the current LispWorks library. When running a delivered LispWorks image, you should specify the :fallback-resources key if your application needs fallback resources.
(capi:convert-to-screen)
CAPI User Guide and Reference Manual (Macintosh version) - 18 Feb 2025 15:33:09