Source Code for Module AEEvent.SelectorChange

  1  ''' 
  2  Defines an L{AEEvent} indicating that the selector has moved. 
  3   
  4  @author: Pete Brunet 
  5  @organization: IBM Corporation 
  6  @copyright: Copyright (c) 2005, 2007 IBM Corporation 
  7  @license: The BSD License 
  8   
  9  All rights reserved. This program and the accompanying materials are made  
 10  available under the terms of the BSD license which accompanies 
 11  this distribution, and is available at 
 12  U{http://www.opensource.org/licenses/bsd-license.php} 
 13  ''' 
 14   
 15  import Base, AEConstants 
 16  from AEConstants import LAYER_FOCUS 
 17   
 18 -class SelectorChange(Base.AccessEngineEvent): 
 19    ''' 
 20    Event that fires when the selector moves. 
 21     
 22    This class registers its name and whether it should be monitored by default in 
 23    an L{AEMonitor} using the L{Base.registerEventType} function 
 24    when this module is first imported. The L{AEMonitor} can use this 
 25    information to build its menus. 
 26     
 27    @ivar text: Accessible text associated with the event, typically the item  
 28      text or the selected text 
 29    @type text: string 
 30    ''' 
 31    Base.registerEventType('SelectorChange', True) 
 32 -  def __init__(self, por, text, kind=AEConstants.EVENT_ACTIVE_ITEM_SELECT,  
 33                 **kwargs): 
 34      '''     
 35      Calls the base class (which set the event priority) and then stores the 
 36      item to be passed along to the Tier as part of the event. 
 37       
 38      @param por: Point-of-regard 
 39      @type por: L{POR} 
 40      @param text: Accessible text associated with the event, typically the  
 41        item text or the selected text 
 42      @type text: string 
 43      @param kind: Kind of selection event 
 44      @type kind: integer 
 45      ''' 
 46      Base.AccessEngineEvent.__init__(self, **kwargs) 
 47      self.text = text 
 48      self.por = por 
 49      self.kind = kind 
 50       
 51 -  def __str__(self): 
 52      ''' 
 53      Returns a human readable representation of this event including its name, 
 54      its L{POR}, and its item text. 
 55       
 56      @return: Information about this event 
 57      @rtype: string 
 58      ''' 
 59      name = Base.AccessEngineEvent.__str__(self) 
 60      if self.kind == AEConstants.EVENT_ACTIVE_ITEM_SELECT: 
 61        action = 'active' 
 62      elif self.kind == AEConstants.EVENT_ADD_ITEM_SELECT: 
 63        action = 'add' 
 64      elif self.kind == AEConstants.EVENT_REMOVE_ITEM_SELECT: 
 65        action = 'remove' 
 66      else: 
 67        action = 'text' 
 68      return '%s:\n\tPOR: %s\n\titem text: %s\n\taction: %s' % \ 
 69        (name, self.por, self.text, action) 
 70     
 71 -  def execute(self, tier_manager, view_manager, **kwargs): 
 72      ''' 
 73      Contacts the L{TierManager} so it can manage the selector change event. 
 74       
 75      @param tier_manager: TierManager that will handle the event 
 76      @type tier_manager: L{TierManager} 
 77      @param kwargs: Packed references to other managers not of interest here 
 78      @type kwargs: dictionary 
 79      @return: True if there is an active view, False if not to delay execution  
 80        of this event until there is 
 81      @rtype: boolean 
 82      ''' 
 83      if view_manager.getAEView() is None and self.layer == LAYER_FOCUS: 
 84        return False 
 85      else: 
 86        tier_manager.manageEvent(self) 
 87        return True 
 88   
 89 -  def getFocusPOR(self): 
 90      ''' 
 91      Returns the L{POR} for active item events. Used by L{Tier} to maintain a  
 92      focus L{POR}. 
 93       
 94      @return: Point-of-regard for this focus event 
 95      @rtype: L{POR} 
 96      @raise AttributeError: When the event does not represent a change in the 
 97        focus 
 98      ''' 
 99      if (self.layer != LAYER_FOCUS or 
100          self.kind != AEConstants.EVENT_ACTIVE_ITEM_SELECT): 
101        raise AttributeError 
102      return self.por 
103   
104 -  def getDataForTask(self): 
105      ''' 
106      Fetches data out of this L{SelectorChange} for use by a 
107      L{Task.SelectorTask}. 
108       
109      @return: Dictionary of parameters to be passed to a 
110        L{Task.SelectorTask} as follows: 
111          - por: The L{POR} pointing at the item at which selection changed or 
112                 the current caret location for a text selection change 
113          - text: The text now selected or unselected 
114          - kind: The kind of selection change 
115      @rtype: dictionary 
116      ''' 
117      return {'por':self.getPOR(), 'text':self.text, 'kind':self.kind} 
118