# 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
# This file abstracts GUI stuff away, so that the actual dsl.py does not have to deal with it
import sys
-# 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)
-
- def error(message):
- '''Displays a fatal error to the user'''
- QtGui.QMessageBox.critical(None, 'Fatal error', message)
-
- def setup(internalResolutions, externalResolutions):
- '''Returns a ScreenSetup instance, or None if the user canceled'''
- 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'
+'''
+This module implements two functions:
+
+def error(message):
+ 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.
+'''
+import subprocess, collections
+
+from question_frontend import QuestionFrontend
+from screen import processOutputIt
+
+# 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, situation):
+ from qt_dialogue import PositionSelection
+ return PositionSelection(situation).run()
+
+ @staticmethod
+ def isAvailable():
+ try:
+ import PyQt4
+ return True
+ except ImportError:
+ return False
+
+
+# Zenity frontend
+class ZenityFrontend(QuestionFrontend):
+ def error(self, message):
+ '''Displays a fatal error to the user'''
+ subprocess.check_call(["zenity", "--error", "--text="+message])
+ def userChoose (self, title, choices, returns, fallback):
+ assert len(choices) == len(returns)
+ args = ["zenity", "--list", "--text="+title, "--column="]+choices
+ switch = dict (list(zip (choices,returns)))
+ try:
+ for line in processOutputIt(*args):
+ return switch.get(line.strip(), fallback)
+ except Exception:
+ # on user cancel, the return code of zenity is nonzero
+ return fallback
+ # if the output was empty
+ return fallback
+ def isAvailable():
+ try:
+ processOutputIt("zenity", "--version")
+ return True
+ except FileNotFoundError:
+ return False
+ except PermissionError:
+ return False
+
+# CLI frontend
+class CLIFrontend(QuestionFrontend):
+ def error(self, message):
+ print(message, file=sys.stderr)
+
+ def userChoose (self, title, choices, returns, fallback):
+ while True:
+ # print question
+ print(title)
+ for i in range(len(choices)):
+ print("%d. %s"%(i,choices[i]))
+ print("Enter 'c' to cancel.")
+ # handle input
+ answer = input("> ")
+ if answer == "c":
+ return None
+ #else
+ try:
+ answerint = int(answer)
+ if answerint >= 0 and answerint < len(choices):
+ return returns[answerint]
+ except ValueError:
+ pass
+ # if we are here something invalid was entered
+ print("INVALID ANSWER: '%s'" % answer)
+
+ @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
+ 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")
projects / lilass.git / blobdiff