zeroinstall/gtkui/treetips.py

   1 """Add tooltips to a TreeView."""
   2 # Copyright (C) 2009, Thomas Leonard
   3 # See the README file for details, or visit http://0install.net.
   4
   5 from zeroinstall import _
   6 import time, gobject, gtk
   7
   8 class TreeTips:
   9         """This object allows you to set location-dependent tooltips on a TreeView.
  10         Connect your TreeView's leave-notify-event to the L{hide} method.
  11         In your motion-notify-event handler, call L{prime} when the pointer moves
  12         to an area with a new message. The message will be shown after a delay.
  13         If calculation of the message is expensive, override L{get_tooltip_text}
  14         instead.
  15         """
  16         timeout = None
  17         widget = None
  18         item = None
  19         time = 0
  20
  21         def show(self, parent):
  22                 if self.timeout:
  23                         gobject.source_remove(self.timeout)
  24                         self.timeout = None
  25
  26                 if self.widget:
  27                         self.widget.destroy()
  28                         self.widget = None
  29
  30                 if self.item is None:
  31                         return
  32
  33                 text = self.get_tooltip_text()
  34                 if not text:
  35                         return
  36
  37                 self.widget = gtk.Window(gtk.WINDOW_POPUP)
  38                 self.widget.set_app_paintable(True)
  39                 self.widget.set_name('gtk-tooltips')
  40
  41                 self.widget.connect('expose-event', self.tooltip_draw)
  42
  43                 label = gtk.Label(text)
  44                 label.set_line_wrap(True)
  45                 label.set_padding(4, 2)
  46                 self.widget.add(label)
  47                 label.show()
  48
  49                 w, h = self.widget.size_request()
  50                 if hasattr(parent, 'get_screen'):
  51                         screen = parent.get_screen()
  52                         root = screen.get_root_window()
  53                 else:
  54                         root = gtk.gdk.get_default_root_window()
  55                 px, py, mask = gtk.gdk.Window.get_pointer(root)
  56
  57                 #m = gtk.gdk.screen_get_default().get_monitor_at_point(px, py)
  58
  59                 x = px - w / 2
  60                 y = py + 12
  61
  62                 # Test if pointer is over the tooltip window
  63                 if py >= y and py <= y + h:
  64                         y = py - h - 2
  65                 self.widget.move(x, y)
  66                 self.widget.show()
  67
  68                 self.widget.connect('destroy', self.tooltip_destroyed)
  69                 self.time = time.time()
  70
  71         def prime(self, parent, item):
  72                 """Call this whenever the pointer moves to an area with a different
  73                 tooltip.
  74                 @param parent: the TreeView widget
  75                 @param item: the text to display
  76                 @see L{get_tooltip_text}"""
  77                 self.hide()
  78                 assert self.timeout is None
  79                 self.item = item
  80
  81                 now = time.time()
  82                 if now - self.time > 2:
  83                         delay = 1000
  84                 else:
  85                         delay = 100
  86
  87                 self.timeout = gobject.timeout_add(delay, lambda: self.show(parent))
  88
  89         def tooltip_draw(self, widget, ev):
  90                 widget.window.draw_rectangle(widget.style.fg_gc[widget.state],
  91                                         False, 0, 0,
  92                                         widget.allocation.width - 1,
  93                                         widget.allocation.height - 1)
  94
  95         def tooltip_destroyed(self, widget):
  96                 pass
  97
  98         def hide(self):
  99                 """Hide the tooltip, if any.
 100                 Sets L{item} to None."""
 101                 self.item = None
 102                 self.show(None)
 103
 104         def get_tooltip_text(self):
 105                 """"Converts the object passed to L{prime} to a string for display.
 106                 The default implementation just calls C{str}, but subclasses can override it.
 107                 @return: the tooltip message"""
 108                 return str(self.item)