remove spurious spaces

[lilass.git] / gui.py

diff --git a/gui.py b/gui.py
index 6dabe0f048df2f0e47bc8dfa363a785bcc3266f2..4847668630baea6c0642a1eac74ea47e5ea32f30 100644 (file)
--- a/gui.py
+++ b/gui.py
@@ -1,5 +1,5 @@
 # DSL - easy Display Setup for Laptops
-# Copyright (C) 2012 Ralf Jung <post@ralfj.de>
+# Copyright (C) 2012-2015 Ralf Jung <post@ralfj.de>
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -16,55 +16,44 @@
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 
 # This file abstracts GUI stuff away, so that the actual dsl.py does not have to deal with it
-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.
 '''
-
-# frontend detectors
-def qtAvailable():
-       try:
-               import PyQt4
-               return True
-       except ImportError:
-               return False
-
-def zenityAvailable():
-       try:
-               from dsl import processOutputIt
-               processOutputIt("zenity", "--version")
-               return True
-       except Exception:
-               return False
-
-# 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()
-
-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'
+import collections
+
+from qt_frontend import QtFrontend
+from cli_frontend import CLIFrontend
+from zenity_frontend import ZenityFrontend
+
+
+# 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
+            else:
+                raise Exception("Frontend %s not available" % name)
+        # frontend not found
+        raise Exception("Frontend %s not found" % 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")