Source Code for Module fife.extensions.pychan.autoposition

  1  # -*- coding: utf-8 -*- 
  2   
  3  # #################################################################### 
  4  #  Copyright (C) 2005-2009 by the FIFE team 
  5  #  http://www.fifengine.de 
  6  #  This file is part of FIFE. 
  7  # 
  8  #  FIFE is free software; you can redistribute it and/or 
  9  #  modify it under the terms of the GNU Lesser General Public 
 10  #  License as published by the Free Software Foundation; either 
 11  #  version 2.1 of the License, or (at your option) any later version. 
 12  # 
 13  #  This library is distributed in the hope that it will be useful, 
 14  #  but WITHOUT ANY WARRANTY; without even the implied warranty of 
 15  #  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU 
 16  #  Lesser General Public License for more details. 
 17  # 
 18  #  You should have received a copy of the GNU Lesser General Public 
 19  #  License along with this library; if not, write to the 
 20  #  Free Software Foundation, Inc., 
 21  #  51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA 
 22  # #################################################################### 
 23   
 24  """ 
 25  Automatic widget positioning 
 26  ============================ 
 27   
 28  You can use the C{position_techinque} attribute 
 29  on top level widgets which can also be set from xml. 
 30   
 31  For direct use call L{placeWidget}. 
 32  """ 
 33   
 34  from internal import screen_width, screen_height 
 35  from exceptions import PyChanException 
 36   
 37  EXPLICIT = "explicit" 
 38  AUTOMATIC = "automatic" 
 39   
 40  TOP = "top" 
 41  LEFT = "left" 
 42  RIGHT = "right" 
 43  CENTER = "center" 
 44  BOTTOM = "bottom" 
 45   
 46   
 47 -def _splicePosition(p): 
 48          if "+" in p: 
 49                  technique,delta = p.split("+") 
 50          elif "-" in p: 
 51                  technique,delta = p.split("-") 
 52                  delta = '-' + delta 
 53          else: 
 54                  technique,delta = p,0 
 55          delta = int(delta) 
 56          return technique,delta 
 57   
 58 -def _parsePosition(position): 
 59          try: 
 60                  if position == AUTOMATIC: 
 61                          position = "center+0:center+0" 
 62   
 63                  x_pos,y_pos = position.split(":") 
 64                  x_pos, x_delta = _splicePosition(x_pos) 
 65                  y_pos, y_delta = _splicePosition(y_pos) 
 66   
 67                  if x_pos not in [EXPLICIT,LEFT,CENTER,RIGHT]: 
 68                          raise  
 69                  if y_pos not in [EXPLICIT,TOP,CENTER,BOTTOM]: 
 70                          raise 
 71          except: 
 72                  raise PyChanException("Malformed position definition: " + repr(position)) 
 73          return x_pos,x_delta,y_pos,y_delta 
 74   
 75 -def placeWidget(widget,position): 
 76          """ 
 77          Place a widget according to a string defining relative coordinates to screen borders. 
 78   
 79          The position definition has to be of the form: C{"<x_pos><x_delta>:<y_pos><y_delta>"} 
 80   
 81          C{<x_pos>} may be one of: 
 82            - left 
 83            - right 
 84            - center 
 85            - explicit 
 86   
 87          C{<y_pos>} may be one of: 
 88            - top 
 89            - bottom 
 90            - center 
 91            - explicit 
 92   
 93          C{explicit} means that the widgets x or y position will not be touched. The rest should be 
 94          self explanatory. 
 95   
 96          C{<x_delta>} and C{<y_delta>} must be of the form: +pixel_number or -pixel_number. Or comletely 
 97          omitted. Note that the sign has to be there for for positive deltas, too. 
 98   
 99          For brevity two shortcuts exist: 
100            - "explict" -> "explict:explict" 
101            - "automatic" -> "center:center" 
102           
103          A few examples:: 
104            "right-20:top" 
105            "center:top+10" 
106            "center:center" 
107   
108          @param widget: The PyChan widget. 
109          @param position: A position definition. 
110   
111          If the position cannot be parsed a L{PyChanException} is thrown. 
112   
113          """ 
114          if position == EXPLICIT: 
115                  return 
116          x_pos,x_delta,y_pos,y_delta = _parsePosition(position) 
117   
118          x,y = widget.position 
119          w,h = widget.size 
120   
121          if x_pos == CENTER: 
122                  x = (screen_width()-w)/2 + x_delta 
123   
124          if y_pos == CENTER: 
125                  y = (screen_height()-h)/2 + y_delta 
126   
127          if x_pos == LEFT: 
128                  x = x_delta 
129   
130          if y_pos == TOP: 
131                  y = y_delta 
132   
133          if x_pos == RIGHT: 
134                  x = screen_width() - w + x_delta 
135   
136          if y_pos == BOTTOM: 
137                  y = screen_height() - h + y_delta 
138   
139          widget.position = x,y 
140