hg/stx-libview: comparison DeviceWorkstation.st

equal deleted inserted replaced

-:692c2f62d94e
+:9a28ea48ec73
 		altModifiers metaModifiers ctrlModifiers shiftModifiers
 		supportsDeepIcons preferredIconSize ditherColors fixColors
 		numFixRed numFixGreen numFixBlue copyBuffer lastCopyBuffer
 		blackColor whiteColor'
 	classVariableNames:'ButtonTranslation MultiClickTimeDelta DeviceErrorSignal
-		DeviceIOErrorSignal ErrorPrinting DefaultScreen AllScreens ExitOnLastClose
+		DeviceIOErrorSignal ErrorPrinting DefaultScreen AllScreens
-		CurrentScreenQuerySignal LastActiveScreen LastActiveProcess'
+		ExitOnLastClose CurrentScreenQuerySignal LastActiveScreen
+		LastActiveProcess'
 	poolDictionaries:''
 	category:'Interface-Graphics'
 !
 !DeviceWorkstation class methodsFor:'documentation'!
 One particular device instance is bound to the global variable Display:
 this is the default graphics display, on which new views are created
 (however, provisions exist for multi-display operation)
-Currently, there is are only two concrete display classes (released to the public):
+Currently, there is are twoconcrete display classes (released to the public):
-	XWorkstation    - a plain X window interface
+XWorkstation    - a plain X window interface
-	GLXWorkstation  - an X window interface with a GL(tm) (3D graphic library)
+GLXWorkstation  - an X window interface with a GL(tm) (3D graphic library)
-			  extension; either simulated (VGL) or a real GL
+extension; either simulated (VGL) or a real GL
-			  (real GL is only available on SGI machines)
+(real GL is only available on SGI machines)
 the following are coming soon:
-	OpenGLWorkstation
+OpenGLWorkstation
-			- an X window interface with a openGL(tm) (3D graphic library)
+- an X window interface with a openGL(tm) (3D graphic library)
-			  extension; either simulated (MESA) or a real openGL
+extension; either simulated (MESA) or a real openGL
-			  (real openGL is only available on SGI/NT machines)
+(real openGL is only available on SGI/NT machines)
-	WinWorkstation  - what will that be ?
+WinWorkstation  - what will that be ?
 An experimental version for a NeXTStep interface exists, but is currently
 no longer maintained and not released.
-Also, interfaces for other graphic systems (i.e. OS/2) are
-planned for and will be available (hopefully) in late 96.
 DeviceWorkstation itself is an abstract class; the methods as defined
 here perform things which are common to all graphic devices or block
 methods and raise a subclassResponsibilty error condition.
-To create a new graphic interface, at least the subclassResponsibilty-methods
+To create a new graphic interface, at least the subclassResponsibility-methods
 have to be reimplemented in a concrete subclass.
-ST/X is designed to allow the use of multiple workstation devices in parallel, if
+ST/X is designed to allow the use of multiple workstation devices in parallel,
-the underlying window system supports this.
+if the underlying window system supports this.
 For example, in X, it is possible to create another instance of XWorkstation,
 start a dispatch process for it, and to create and open views on this display.
-This does not work with other devices (i.e. Windows).
+Multiple display operation does not work with other devices (i.e. Windows).
 If you want to experiment with multi-display applications,
 you have to:
-	- create a new instance of XWorkstation:
+- create a new instance of XWorkstation:
-	    Smalltalk at:#Display2 put:(XWorkstation new).
+Smalltalk at:#Display2 put:(XWorkstation new).
-	  or:
+or:
-	    Smalltalk at:#Display2 put:(GLXWorkstation new).
+Smalltalk at:#Display2 put:(GLXWorkstation new).
-	- have it connect to the display (i.e. the xServer):
+- have it connect to the display (i.e. the xServer):
-	  (replace 'localhost' below with the name of your display)
+(replace 'localhost' below with the name of your display)
-	    Display2 := Display2 initializeFor:'localhost:0.0'
+Display2 := Display2 initializeFor:'localhost:0.0'
-	  returns nil, if connection is refused
+returns nil, if connection is refused
-	  - leaving you with Display2==nil in this case.
+- leaving you with Display2==nil in this case.
-	- start an event dispatcher process for it:
+- start an event dispatcher process for it:
-	  (this is now no longer needed - the first opened view will do it for you)
+(this is now no longer needed - the first opened view will do it for you)
-	    Display2 startDispatch
+Display2 startDispatch
-	- optionally set its keyboard map
+- optionally set its keyboard map
-	  (since this is usually done for Display in the startup-file,
+(since this is usually done for Display in the startup-file,
-	   the new display does not have all your added key bindings)
+the new display does not have all your added key bindings)
-	    Display2 keyboardMap:(Display keyboardMap)
+Display2 keyboardMap:(Display keyboardMap)
-	- create a view for it:
+- create a view for it:
-	    (FileBrowser onDevice:Display2) open
+(FileBrowser onDevice:Display2) open
-	    (Workspace onDevice:Display2) open
+(Workspace onDevice:Display2) open
-	    (Launcher onDevice:Display2) open
+(Launcher onDevice:Display2) open
-		does not work with Launcher, since its an ApplicationModel (not a view)
+does not work with Launcher, since its an ApplicationModel (not a view)
-		use:
+use:
-		    Launcher openOnDevice:Display2
+Launcher openOnDevice:Display2
-		instead.
+instead.
 However, as mentioned above, there may be a few places, where the default
 display 'Display' is still hard-coded - especially, in contributed and
 Public domain code, you may find those.
 Beside this (little bug ;-), remote display operation works pretty well.
 If you write your application to work around those, multi-display applications are
-possible in the current release.
+possible in the current release (and actually being used in a concrete application,
+where up to 6 x-terminals are connected to a single linux PC).
 To make your application ready for multi-display operation, replace all
 references to 'Display' by: 'Screen current', which evaluates to the currently
 active display. I.e. each view gets its actual display via this expression.
 Since ST/X views already use this, new views opened by remote views should
 There is no easy solution for things like Notifiers, WarnBoxes or
 Debuggers when opened from some background or non-view process.
 These will come up one the default Display, as returned by 'Screen default'.
+Finally, your application should care for I/O errors (i.e. lost connection when
+a remote display is switched off).
+The framework provides per-display signals, which are raised in the corresponding
+event dispatchers context.
+For a save environment, you should add static exception handler blocks on those
+signals; i.e. the setup for remote displays should look somewhat like:
+|newDpy|
+newDpy := GLXWorkstation new.
+newDpy := newDpy initializeFor:'localhost:0.0'.
+newDpy isNil ifTrue:[
+self warn:'cannot connect ...'.
+] ifFalse:[
+newDpy deviceIOErrorSignal handlerBlock:[:ex |
+Transcript beep.
+Transcript showCR:'Display (' , newDpy displayName , '): connection broken.'.
+AbortSignal raise.
+].
+newDpy startDispatch.
+Launcher openOnDevice:newDpy.
+].
 There may still some problems to be expected,
 if the screens have different display capabilities (b&w vs. greyscale vs.
 color display). The current styleSheet approach keeps default values
-only once (it should do so per display ...) For now, expect ugly looking
+only once (it should do so per display ...)
-views in this case - or set your styleSheet for the smallest common
+For now, expect ugly looking views in this case - or set your styleSheet
-capabilities (i.e. for b&w).
+for the smallest common capabilities (i.e. for b&w).
+This may be fixed in a future version ...
 "
 ! !
 !DeviceWorkstation class methodsFor:'initialization'!
 "return the signal used for device I/O error reporting.
 In multi-display configurations, this is the parent of
 all per-instance deviceIOErrorSignals."
 ^ DeviceIOErrorSignal
-! !
-!DeviceWorkstation methodsFor:'Signal constants'!
-deviceErrorSignal
-"return the per-device signal, which is used for error reporting.
-The default here is the global DeviceErrorSignal (which is the
-parent of the per-instance signals)."
-^ self class deviceErrorSignal
-!
-deviceIOErrorSignal
-"return the signal used for device I/O error reporting.
-The default here is the global DeviceIOErrorSignal (which is the
-parent of the per-instance signals)."
-^ self class deviceIOErrorSignal
 ! !
 !DeviceWorkstation class methodsFor:'accessing'!
 buttonTranslation:anArray
 Screen current zoom:(20@20 corner:1000@1000) to:(10@10 corner:20@20) speed:2000
 "
 "Created: 27.1.1997 / 18:19:35 / cg"
 "Modified: 27.1.1997 / 18:24:58 / cg"
+! !
+!DeviceWorkstation methodsFor:'Signal constants'!
+deviceErrorSignal
+"return the per-device signal, which is used for error reporting.
+The default here is the global DeviceErrorSignal (which is the
+parent of the per-instance signals)."
+^ self class deviceErrorSignal
+!
+deviceIOErrorSignal
+"return the signal used for device I/O error reporting.
+The default here is the global DeviceIOErrorSignal (which is the
+parent of the per-instance signals)."
+^ self class deviceIOErrorSignal
 ! !
 !DeviceWorkstation methodsFor:'accessing & queries'!
 buttonMotionMask:aMask includesButton:aButton
 ! !
 !DeviceWorkstation class methodsFor:'documentation'!
 version
-^ '$Header: /cvs/stx/stx/libview/DeviceWorkstation.st,v 1.204 1997-04-11 09:35:21 cg Exp $'
+^ '$Header: /cvs/stx/stx/libview/DeviceWorkstation.st,v 1.205 1997-04-11 10:40:02 cg Exp $'
 ! !
 DeviceWorkstation initialize!

changeset 1580	9a28ea48ec73
parent 1578	01db7f44cbbd
child 1582	ec428aba3f9c