From: Ralf Jung <post@ralfj.de>
Date: Wed, 17 Oct 2012 14:20:21 +0000 (+0200)
Subject: rework GUI frontend selection
X-Git-Url: https://git.ralfj.de/lilass.git/commitdiff_plain/4c3831b98072b3668350cd8c4140383f85484c4c?hp=f9da06538394990906d6148d7cbc2dad7a7967c7

rework GUI frontend selection
---

diff --git a/gui.py b/gui.py
index 83099e8..155226b 100644
--- a/gui.py
+++ b/gui.py
@@ -18,26 +18,36 @@
 # This file abstracts GUI stuff away, so that the actual dsl.py does not have to deal with it
 import sys
 
-qt_available = True
-try:
+# frontend detectors
+def qtAvailable():
+	try:
+		import PyQt4
+		return True
+	except ImportError:
+		return False
+
+def zenityAvailable():
+	return True # FIXME
+
+# actual frontend
+if qtAvailable():
 	from PyQt4 import QtGui
 	from qt_dialogue import PositionSelection
 	app = QtGui.QApplication(sys.argv)
-except Exception, e:
-	import subprocess
-	from zenity_dialogue import run as zenity_run
-	qt_available = False
-
-def error(message):
-	'''Displays a fatal error to the user'''
-	if qt_available:
+	
+	def error(message):
+		'''Displays a fatal error to the user'''
 		QtGui.QMessageBox.critical(None, 'Fatal error', message)
-	else:
-		subprocess.check_call(["zenity", "--error", "--text="+message])
-
-def setup(internalResolutions, externalResolutions):
-	'''Returns a ScreenSetup instance, or None if the user canceled'''
-	if qt_available:
+	
+	def setup(internalResolutions, externalResolutions):
+		'''Returns a ScreenSetup instance, or None if the user canceled'''
 		return PositionSelection(internalResolutions, externalResolutions).run()
-	else:
-		return zenity_run(internalResolutions, externalResolutions)
+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'