Source Code for Module pyjamas.ui.ScrollPanel

  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.SimplePanel import SimplePanel 
 19  from pyjamas.ui import Event 
 20   
 21 -class ScrollPanel(SimplePanel): 
 22   
 23      _props = [("always", "Always show scroll bars", 
 24                                "AlwaysShowScrollBars", None), 
 25               ("position", "Vertical Scroll Position", 
 26                                "ScrollPosition", None), 
 27               ("horizPos", "Horizontal Scroll Position", 
 28                                "HorizontalScrollPosition", None), 
 29              ] 
 30   
 31 -    def __init__(self, child=None, **kwargs): 
 32          self.scrollListeners = [] 
 33   
 34          if child is not None: 
 35              kwargs['Widget'] = child 
 36          if not kwargs.has_key('AlwaysShowScrollBars'): 
 37               kwargs['AlwaysShowScrollBars'] = False 
 38   
 39          SimplePanel.__init__(self, **kwargs) 
 40          self.sinkEvents(Event.ONSCROLL) 
 41   
 42      @classmethod 
 43 -    def _getProps(self): 
 44          return SimplePanel._getProps() + self._props 
 45   
 46      # next three functions are part of the standard Builder API for panels 
 47 -    def addIndexedItem(self, index, item): 
 48          self.setWidget(item) 
 49   
 50 -    def getWidgetIndex(self, index): 
 51          return 0 
 52   
 53 -    def getIndexedChild(self, index): 
 54          return self.getWidget() 
 55   
 56 -    def addScrollListener(self, listener): 
 57          self.scrollListeners.append(listener) 
 58   
 59 -    def ensureVisible(self, item): 
 60          scroll = self.getElement() 
 61          element = item.getElement() 
 62          self.ensureVisibleImpl(scroll, element) 
 63   
 64 -    def getScrollPosition(self): 
 65          return DOM.getIntAttribute(self.getElement(), "scrollTop") 
 66   
 67 -    def getHorizontalScrollPosition(self): 
 68          return DOM.getIntAttribute(self.getElement(), "scrollLeft") 
 69   
 70 -    def onBrowserEvent(self, event): 
 71          type = DOM.eventGetType(event) 
 72          if type == "scroll": 
 73              for listener in self.scrollListeners: 
 74                  listener.onScroll(self, self.getHorizontalScrollPosition(), 
 75                                          self.getScrollPosition()) 
 76   
 77 -    def removeScrollListener(self, listener): 
 78          self.scrollListeners.remove(listener) 
 79   
 80 -    def setAlwaysShowScrollBars(self, alwaysShow): 
 81          if alwaysShow: 
 82              style = "scroll" 
 83          else: 
 84              style = "auto" 
 85          DOM.setStyleAttribute(self.getElement(), "overflow", style) 
 86   
 87 -    def setScrollPosition(self, position): 
 88          DOM.setIntAttribute(self.getElement(), "scrollTop", position) 
 89   
 90 -    def setHorizontalScrollPosition(self, position): 
 91          DOM.setIntAttribute(self.getElement(), "scrollLeft", position) 
 92   
 93 -    def ensureVisibleImpl(self, scroll, e): 
 94          if not e: 
 95              return 
 96          item = e 
 97          realOffset = 0 
 98          while item and (item != scroll): 
 99              realOffset += item.offsetTop 
100              item = item.offsetParent 
101          scroll.scrollTop = realOffset - scroll.offsetHeight / 2 
102   
103  Factory.registerClass('pyjamas.ui.ScrollPanel', 'ScrollPanel', ScrollPanel) 
104