Source Code for Module library.pyjamas.ui.Widget

  1  # Copyright 2006 James Tauber and contributors 
  2  # Copyright (C) 2009 Luke Kenneth Casson Leighton <lkcl@lkcl.net> 
  3  # 
  4  # Licensed under the Apache License, Version 2.0 (the "License"); 
  5  # you may not use this file except in compliance with the License. 
  6  # You may obtain a copy of the License at 
  7  # 
  8  #     http://www.apache.org/licenses/LICENSE-2.0 
  9  # 
 10  # Unless required by applicable law or agreed to in writing, software 
 11  # distributed under the License is distributed on an "AS IS" BASIS, 
 12  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
 13  # See the License for the specific language governing permissions and 
 14  # limitations under the License. 
 15  from pyjamas import DOM 
 16  from pyjamas import Factory 
 17   
 18  from pyjamas.ui.UIObject import UIObject 
 19  from pyjamas.ui import Event 
 20  from pyjamas.ui.ClickListener import ClickHandler 
 21  from pyjamas.ui.FocusListener import FocusHandler 
 22  from pyjamas.ui.KeyboardListener import KeyboardHandler 
 23  from pyjamas.ui.MouseListener import MouseHandler, MouseWheelHandler 
 24  from pyjamas.ui.InputListener import InputHandler 
 25  from pyjamas.ui.ChangeListener import ChangeHandler 
 26  from pyjamas.ui.DragHandler import DragHandler 
 27  from pyjamas.ui.DropHandler import DropHandler 
 28   
 29 -class Widget(UIObject): 
 30      """ 
 31          Base class for most of the UI classes.  This class provides basic services 
 32          used by any Widget, including management of parents and adding/removing the 
 33          event handler association with the DOM. 
 34      """ 
 35 -    def __init__(self, **kwargs): 
 36          self.attached = False 
 37          self.parent = None 
 38          self.layoutData = None 
 39          self.contextMenu = None 
 40   
 41          UIObject.__init__(self, **kwargs) 
 42   
 43 -    def getLayoutData(self): 
 44          return self.layoutData 
 45   
 46 -    def getParent(self): 
 47          """Widgets are kept in a hierarchy, and widgets that have been added to a panel 
 48          will have a parent widget that contains them.  This retrieves the containing 
 49          widget for this widget.""" 
 50          return self.parent 
 51   
 52 -    def isAttached(self): 
 53          """Return whether or not this widget has been attached to the document.""" 
 54          return self.attached 
 55   
 56 -    def setContextMenu(self, menu): 
 57          self.contextMenu = menu 
 58          if menu is not None: 
 59              self.sinkEvents(Event.ONCONTEXTMENU) 
 60          else: 
 61              self.unsinkEvents(Event.ONCONTEXTMENU) 
 62   
 63 -    def onBrowserEvent(self, event): 
 64   
 65          # farm out the event to convenience handlers. 
 66          # detect existence by checking for the listener lists of each 
 67          # type of handler.  there's probably a better way to do this... 
 68          if hasattr(self, "_clickListeners"): 
 69              ClickHandler.onBrowserEvent(self, event) 
 70          if hasattr(self, "_keyboardListeners"): 
 71              KeyboardHandler.onBrowserEvent(self, event) 
 72          if hasattr(self, "_mouseListeners"): 
 73              MouseHandler.onBrowserEvent(self, event) 
 74          if hasattr(self, "_mouseWheelListeners"): 
 75              MouseWheelHandler.onBrowserEvent(self, event) 
 76          if hasattr(self, "_focusListeners"): 
 77              FocusHandler.onBrowserEvent(self, event) 
 78          if hasattr(self, "_dragListeners"): 
 79              DragHandler.onBrowserEvent(self, event) 
 80          if hasattr(self, "_changeListeners"): 
 81              ChangeHandler.onBrowserEvent(self, event) 
 82          if hasattr(self, "_inputListeners"): 
 83              InputHandler.onBrowserEvent(self, event) 
 84          if hasattr(self, "_dropListeners"): 
 85              DropHandler.onBrowserEvent(self, event) 
 86   
 87          if self.contextMenu is None: 
 88              return True 
 89   
 90          type = DOM.eventGetType(event) 
 91          if type == "contextmenu": 
 92              DOM.eventCancelBubble(event, True) 
 93              DOM.eventPreventDefault(event) 
 94              self.contextMenu.onContextMenu(self) 
 95              return False 
 96   
 97          return True 
 98   
 99 -    def onLoad(self): 
100          pass 
101   
102 -    def doDetachChildren(self): 
103          pass 
104   
105 -    def doAttachChildren(self): 
106          pass 
107   
108 -    def onAttach(self): 
109          """Called when this widget has an element, and that element is on the document's 
110          DOM tree, and we have a parent widget.""" 
111          if self.isAttached(): 
112              return 
113          self.attached = True 
114          DOM.setEventListener(self.getElement(), self) 
115          self.doAttachChildren() 
116          self.onLoad() 
117   
118 -    def onDetach(self): 
119          """Called when this widget is being removed from the DOM tree of the document.""" 
120          if not self.isAttached(): 
121              return 
122          self.doDetachChildren() 
123          self.attached = False 
124          DOM.setEventListener(self.getElement(), None) 
125   
126 -    def setLayoutData(self, layoutData): 
127          self.layoutData = layoutData 
128   
129 -    def setParent(self, parent): 
130          """Update the parent attribute.  If the parent is currently attached to the DOM this 
131          assumes we are being attached also and calls onAttach().""" 
132          oldparent = self.parent 
133          self.parent = parent 
134          if parent is None: 
135              if oldparent is not None and oldparent.attached: 
136                  self.onDetach() 
137          elif parent.attached: 
138              self.onAttach() 
139   
140 -    def removeFromParent(self): 
141          """Remove ourself from our parent.  The parent widget will call setParent(None) on 
142          us automatically""" 
143          if hasattr(self.parent, "remove"): 
144              self.parent.remove(self) 
145   
146 -    def getID(self): 
147          """Get the id attribute of the associated DOM element.""" 
148          return DOM.getAttribute(self.getElement(), "id") 
149   
150 -    def setID(self, id): 
151          """Set the id attribute of the associated DOM element.""" 
152          DOM.setAttribute(self.getElement(), "id", id) 
153   
154  Factory.registerClass('pyjamas.ui.Widget', 'Widget', Widget) 
155