X-Git-Url: https://git.ralfj.de/lilass.git/blobdiff_plain/0d513b43eb63d88ff9b1262dedda26b330d2505e..4dd0918b62956f292f8448c32d8c61fbbeacfeb4:/gui.py?ds=sidebyside

diff --git a/gui.py b/gui.py
index b3929cb..40cafa5 100644
--- a/gui.py
+++ b/gui.py
@@ -22,44 +22,88 @@ import sys
 This module implements two functions:
 
 def error(message):
-	This function displays the error message to the user in some appropriate fassion
+    This function displays the error message to the user in some appropriate fassion
 
 def setup(internalResolutions, externalResolutions):
-	Both arguments are lists of (width, height) tuples of resolutions. You can use dsl.res2user to obtain a user-readable representation of a resolution tuple.
-	The user should be asked about his display setup preferences.
-	The function returns None if the user cancelled, and an instance of dsl.ScreenSetup otherwise.
+    Both arguments are lists of (width, height) tuples of resolutions. You can use dsl.res2user to obtain a user-readable representation of a resolution tuple.
+    The user should be asked about his display setup preferences.
+    The function returns None if the user cancelled, and an instance of dsl.ScreenSetup otherwise.
 '''
+import subprocess, collections
 
-# frontend detectors
-def qtAvailable():
-	try:
-		import PyQt4
-		return True
-	except ImportError:
-		return False
+# Qt frontend
+class QtFrontend:
+    def __init__(self):
+        from PyQt4 import QtGui
+        self.app = QtGui.QApplication(sys.argv)
+        print("Qt loaded")
+    
+    def error(self, message):
+        from PyQt4 import QtGui
+        QtGui.QMessageBox.critical(None, 'Fatal error', message)
+    
+    def setup(self, internalResolutions, externalResolutions, commonRes):
+        from qt_dialogue import PositionSelection
+        return PositionSelection(internalResolutions, externalResolutions, commonRes).run()
+    
+    @staticmethod
+    def isAvailable():
+        try:
+            import PyQt4
+            return True
+        except ImportError:
+            return False
 
-def zenityAvailable():
-	return True # FIXME
 
-# actual frontends
-if qtAvailable():
-	from PyQt4 import QtGui
-	from qt_dialogue import PositionSelection
-	app = QtGui.QApplication(sys.argv)
-	
-	def error(message):
-		QtGui.QMessageBox.critical(None, 'Fatal error', message)
-	
-	def setup(internalResolutions, externalResolutions):
-		return PositionSelection(internalResolutions, externalResolutions).run()
+# Zenity frontend
+class ZenityFrontend:
+    def error(message):
+        '''Displays a fatal error to the user'''
+        subprocess.check_call(["zenity", "--error", "--text="+message])
+    
+    def setup(self, internalResolutions, externalResolutions, commonRes):
+        from zenity_dialogue import run
+        return run(internalResolutions, externalResolutions)
+    
+    @staticmethod
+    def isAvailable():
+        try:
+            from dsl import processOutputIt
+            processOutputIt("zenity", "--version")
+            return True
+        except Exception:
+            return False
 
-elif zenityAvailable():
-	import subprocess
-	from zenity_dialogue import run as setup # this provides the setup function
-	
-	def error(message):
-		'''Displays a fatal error to the user'''
-		subprocess.check_call(["zenity", "--error", "--text="+message])
 
-else:
-	print >> sys.stderr, 'No GUI frontend available, please make sure PyQt4 or Zenity is installed'
+# CLI frontend
+class CLIFrontend:
+    def error(self, message):
+        print(message, file=sys.stderr)
+    
+    def setup(self, internalResolutions, externalResolutions, commonRes):
+        raise Exception("Choosing the setup interactively is not supported with the CLI frontend")
+    
+    @staticmethod
+    def isAvailable():
+        return True
+
+# list of available frontends
+frontends = collections.OrderedDict()
+frontends["qt"] = QtFrontend
+frontends["zenity"] = ZenityFrontend
+frontends["cli"] = CLIFrontend
+
+# get a frontend
+def getFrontend(name = None):
+    # by name
+    if name is not None:
+        if name in frontends:
+            if frontends[name].isAvailable():
+                return frontends[name]() # call constructor
+        # frontend not found or not available
+        raise Exception("Frontend %s not found or not available" % name)
+    # auto-detect
+    for frontend in frontends.values():
+        if frontend.isAvailable():
+            return frontend() # call constructor
+    raise Exception("No frontend is available - this should not happen")