wx/lib/wordwrap.py

   1 #----------------------------------------------------------------------
   2 # Name:        wx.lib.wordwrap
   3 # Purpose:     Contains a function to aid in word-wrapping some text
   4 #
   5 # Author:      Robin Dunn
   6 #
   7 # Created:     15-Oct-2006
   8 # RCS-ID:      $Id: wordwrap.py 54718 2008-07-19 18:57:26Z RD $
   9 # Copyright:   (c) 2006 by Total Control Software
  10 # Licence:     wxWindows license
  11 #----------------------------------------------------------------------
  12
  13 def wordwrap(text, width, dc, breakLongWords=True, margin=0):
  14     """
  15     Returns a copy of text with newline characters inserted where long
  16     lines should be broken such that they will fit within the given
  17     width, with the given margin left and right, on the given `wx.DC`
  18     using its current font settings.  By default words that are wider
  19     than the margin-adjusted width will be broken at the nearest
  20     character boundary, but this can be disabled by passing ``False``
  21     for the ``breakLongWords`` parameter.
  22     """
  23
  24     wrapped_lines = []
  25     text = text.split('\n')
  26     for line in text:
  27         pte = dc.GetPartialTextExtents(line)
  28         wid = ( width - (2*margin+1)*dc.GetTextExtent(' ')[0]
  29               - max([0] + [pte[i]-pte[i-1] for i in range(1,len(pte))]) )
  30         idx = 0
  31         start = 0
  32         startIdx = 0
  33         spcIdx = -1
  34         while idx < len(pte):
  35             # remember the last seen space
  36             if line[idx] == ' ':
  37                 spcIdx = idx
  38
  39             # have we reached the max width?
  40             if pte[idx] - start > wid and (spcIdx != -1 or breakLongWords):
  41                 if spcIdx != -1:
  42                     idx = spcIdx + 1
  43                 wrapped_lines.append(' '*margin + line[startIdx : idx] + ' '*margin)
  44                 start = pte[idx]
  45                 startIdx = idx
  46                 spcIdx = -1
  47
  48             idx += 1
  49
  50         wrapped_lines.append(' '*margin + line[startIdx : idx] + ' '*margin)
  51
  52     return '\n'.join(wrapped_lines)
  53
  54
  55
  56 if __name__ == '__main__':
  57     import wx
  58     class TestPanel(wx.Panel):
  59         def __init__(self, parent):
  60             wx.Panel.__init__(self, parent)
  61
  62             self.tc = wx.TextCtrl(self, -1, "", (20,20), (150,150), wx.TE_MULTILINE)
  63             self.Bind(wx.EVT_TEXT, self.OnDoUpdate, self.tc)
  64             self.Bind(wx.EVT_SIZE, self.OnSize)
  65
  66
  67         def OnSize(self, evt):
  68             wx.CallAfter(self.OnDoUpdate, None)
  69
  70
  71         def OnDoUpdate(self, evt):
  72             WIDTH = self.GetSize().width - 220
  73             HEIGHT = 200
  74             bmp = wx.EmptyBitmap(WIDTH, HEIGHT)
  75             mdc = wx.MemoryDC(bmp)
  76             mdc.SetBackground(wx.Brush("white"))
  77             mdc.Clear()
  78             mdc.SetPen(wx.Pen("black"))
  79             mdc.SetFont(wx.Font(10, wx.SWISS, wx.NORMAL, wx.NORMAL))
  80             mdc.DrawRectangle(0,0, WIDTH, HEIGHT)
  81
  82             text = wordwrap(self.tc.GetValue(), WIDTH-2, mdc, False)
  83             #print repr(text)
  84             mdc.DrawLabel(text, (1,1, WIDTH-2, HEIGHT-2))
  85
  86             del mdc
  87             dc = wx.ClientDC(self)
  88             dc.DrawBitmap(bmp, 200, 20)
  89
  90
  91     app = wx.App(False)
  92     frm = wx.Frame(None, title="Test wordWrap")
  93     pnl = TestPanel(frm)
  94     frm.Show()
  95     app.MainLoop()
  96
  97