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 class QObserver(Observer, QObject):
  16
  17         def __init__(self, model, view):
  18                 Observer.__init__(self, model)
  19                 QObject.__init__(self)
  20
  21                 self.view = view
  22
  23                 self.__actions = {}
  24                 self.__callbacks = {}
  25                 self.__model_to_view = {}
  26                 self.__view_to_model = {}
  27
  28         def SLOT(self, *args):
  29                 '''Default slot to handle all Qt callbacks.
  30                 This method delegates to callbacks from add_signals.'''
  31
  32                 widget = self.sender()
  33                 sender = str(widget.objectName())
  34
  35                 if sender in self.__callbacks:
  36                         self.__callbacks[sender](*args)
  37
  38                 elif sender in self.__view_to_model:
  39                         model = self.model
  40                         model_param = self.__view_to_model[sender]
  41                         if isinstance(widget, QTextEdit):
  42                                 value = str(widget.toPlainText())
  43                                 model.set_param(model_param, value,
  44                                                 notify=False)
  45                         elif isinstance(widget, QLineEdit):
  46                                 value = str(widget.text())
  47                                 model.set_param(model_param, value,
  48                                                 notify=False)
  49                         elif isinstance(widget, QCheckBox):
  50                                 model.set_param(model_param, widget.isChecked(),
  51                                                 notify=False)
  52                         elif isinstance(widget, QSpinBox):
  53                                 model.set_param(model_param, widget.value(),
  54                                                 notify=False)
  55                         elif isinstance(widget, QFontComboBox):
  56                                 value = unicode(widget.currentFont().toString())
  57                                 model.set_param(model_param, value,
  58                                                 notify=False)
  59                         else:
  60                                 print("SLOT(): Unknown widget:", sender, widget)
  61
  62         def connect(self, obj, signal_str, *args):
  63                 '''Convenience function so that subclasses do not have
  64                 to import QtCore.SIGNAL.'''
  65                 signal = signal_str
  66                 if type(signal) is str:
  67                         signal = SIGNAL(signal)
  68                 return QObject.connect(obj, signal, *args)
  69
  70         def add_signals(self, signal_str, *objects):
  71                 '''Connects object's signal to the QObserver.'''
  72                 for obj in objects:
  73                         self.connect(obj, signal_str, self.SLOT)
  74
  75         def add_callbacks(self, **callbacks):
  76                 '''Registers callbacks that are called in response to GUI events.'''
  77                 for sender, callback in callbacks.iteritems():
  78                         self.__callbacks[sender] = callback
  79
  80         def model_to_view(self, model_param, *widget_names):
  81                 '''Binds model params to qt widgets(model->view)'''
  82                 self.__model_to_view[model_param] = widget_names
  83                 for widget_name in widget_names:
  84                         self.__view_to_model[widget_name] = model_param
  85
  86         def add_actions(self, model_param, callback):
  87                 '''Register view actions that are called in response to
  88                 view changes.(view->model)'''
  89                 self.__actions[model_param] = callback
  90
  91         def subject_changed(self, param, value):
  92                 '''Sends a model param to the view(model->view)'''
  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
 117                 if param not in self.__actions:
 118                         return
 119                 widgets = []
 120                 if param in self.__model_to_view:
 121                         for widget_name in self.__model_to_view[param]:
 122                                 widget = getattr(self.view, widget_name)
 123                                 widgets.append(widget)
 124                 # Call the model callback w/ the view's widgets as the args
 125                 self.__actions[param](*widgets)
 126
 127         def refresh_view(self):
 128                 params = list(self.__model_to_view.keys())
 129                 for param in self.__actions.keys():
 130                         if param not in params: params.append(param)
 131                 self.model.notify_observers(*params)