ugitlibs/qobserver.py

   1 #!/usr/bin/env python
   2 from PyQt4.QtCore import QObject
   3 from PyQt4.QtCore import SIGNAL
   4 from PyQt4.QtGui import QSpinBox
   5 from PyQt4.QtGui import QPixmap
   6 from PyQt4.QtGui import QTextEdit
   7 from PyQt4.QtGui import QLineEdit
   8 from PyQt4.QtGui import QListWidget
   9 from PyQt4.QtGui import QCheckBox
  10 from PyQt4.QtGui import QFont
  11 from PyQt4.QtGui import QFontComboBox
  12
  13 from observer import Observer
  14
  15
  16 class QObserver(Observer, QObject):
  17
  18         def __init__(self, model, view):
  19                 Observer.__init__(self, model)
  20                 QObject.__init__(self)
  21
  22                 self.view = view
  23
  24                 self.__actions = {}
  25                 self.__callbacks = {}
  26                 self.__model_to_view = {}
  27                 self.__view_to_model = {}
  28
  29         def SLOT(self, *args):
  30                 '''Default slot to handle all Qt callbacks.
  31                 This method delegates to callbacks from add_signals.'''
  32
  33                 widget = self.sender()
  34                 sender = str(widget.objectName())
  35
  36                 if sender in self.__callbacks:
  37                         self.__callbacks[sender](*args)
  38
  39                 elif sender in self.__view_to_model:
  40                         model = self.model
  41                         model_param = self.__view_to_model[sender]
  42                         if isinstance(widget, QTextEdit):
  43                                 value = str(widget.toPlainText())
  44                                 model.set_param(model_param, value,
  45                                                 notify=False)
  46                         elif isinstance(widget, QLineEdit):
  47                                 value = str(widget.text())
  48                                 model.set_param(model_param, value)
  49                         elif isinstance(widget, QCheckBox):
  50                                 model.set_param(model_param, widget.isChecked())
  51                         elif isinstance(widget, QSpinBox):
  52                                 model.set_param(model_param, widget.value())
  53                         elif isinstance(widget, QFontComboBox):
  54                                 value = unicode(widget.currentFont().toString())
  55                                 model.set_param(model_param, value)
  56                         else:
  57                                 print("SLOT(): Unknown widget:", sender, widget)
  58
  59         def connect(self, obj, signal_str, *args):
  60                 '''Convenience function so that subclasses do not have
  61                 to import QtCore.SIGNAL.'''
  62                 signal = signal_str
  63                 if type(signal) is str:
  64                         signal = SIGNAL(signal)
  65                 return QObject.connect(obj, signal, *args)
  66
  67         def add_signals(self, signal_str, *objects):
  68                 '''Connects object's signal to the QObserver.'''
  69                 for obj in objects:
  70                         self.connect(obj, signal_str, self.SLOT)
  71
  72         def add_callbacks(self, **callbacks):
  73                 '''Registers callbacks that are called in response to GUI events.'''
  74                 for sender, callback in callbacks.iteritems():
  75                         self.__callbacks[sender] = callback
  76
  77         def model_to_view(self, model_param, *widget_names):
  78                 '''Binds model params to qt widgets(model->view)'''
  79                 self.__model_to_view[model_param] = widget_names
  80                 for widget_name in widget_names:
  81                         self.__view_to_model[widget_name] = model_param
  82
  83         def add_actions(self, model_param, callback):
  84                 '''Register view actions that are called in response to
  85                 view changes.(view->model)'''
  86                 self.__actions[model_param] = callback
  87
  88         def subject_changed(self, param, value):
  89                 '''Sends a model param to the view(model->view)'''
  90
  91                 notify = self.model.get_notify()
  92                 self.model.set_notify(False)
  93                 if param in self.__model_to_view:
  94                         for widget_name in self.__model_to_view[param]:
  95                                 widget = getattr(self.view, widget_name)
  96                                 if isinstance(widget, QSpinBox):
  97                                         widget.setValue(value)
  98                                 elif isinstance(widget, QPixmap):
  99                                         widget.load(value)
 100                                 elif isinstance(widget, QTextEdit):
 101                                         widget.setText(value)
 102                                 elif isinstance(widget, QLineEdit):
 103                                         widget.setText(value)
 104                                 elif isinstance(widget, QListWidget):
 105                                         widget.clear()
 106                                         for i in value: widget.addItem(i)
 107                                 elif isinstance(widget, QCheckBox):
 108                                         widget.setChecked(value)
 109                                 elif isinstance(widget, QFontComboBox):
 110                                         font = widget.currentFont()
 111                                         font.fromString(value)
 112                                 else:
 113                                         print('subject_changed(): '
 114                                                 + 'Unknown widget:',
 115                                                 widget_name, widget, value)
 116                 self.model.set_notify(notify)
 117
 118                 if param not in self.__actions:
 119                         return
 120                 widgets = []
 121                 if param in self.__model_to_view:
 122                         for widget_name in self.__model_to_view[param]:
 123                                 widget = getattr(self.view, widget_name)
 124                                 widgets.append(widget)
 125                 # Call the model callback w/ the view's widgets as the args
 126                 self.__actions[param](*widgets)
 127
 128         def refresh_view(self):
 129                 params = list(self.__model_to_view.keys())
 130                 for param in self.__actions.keys():
 131                         if param not in params: params.append(param)
 132                 self.model.notify_observers(*params)