class ViewHelper:
"""Controls a specific view for font manipulation."""
def __init__(self, view):
"""Constructor."""
self._view = view
self._scroll_handler = self._view.connect('scroll_event',
self._on_scrolling)
self._fontsize_manipulator = FontsizeManipulator(self._view)
def deactivate(self):
"""Resets the font and disconnects the scroll-event."""
self.reset_font()
self._view.disconnect(self._scroll_handler)
def _on_scrolling(self, view, event):
"""Callback on scroll wheel movement."""
event_consumed = False
if (event.state & gtk.gdk.CONTROL_MASK):
if event.direction == gtk.gdk.SCROLL_UP:
self.enlarge_font()
event_consumed = True
elif event.direction == gtk.gdk.SCROLL_DOWN:
self.shrink_font()
event_consumed = True
return event_consumed
def enlarge_font(self):
"""Enlarges the font of this view."""
self._fontsize_manipulator.enlarge()
def shrink_font(self):
"""Shrinks the font of this view."""
self._fontsize_manipulator.shrink()
def reset_font(self):
"""Resets the font of this view to ist original size."""
self._fontsize_manipulator.reset()
def __init__(self, view):
"""Constructor."""
self._view = view
self._scroll_handler = self._view.connect('scroll_event',
self._on_scrolling)
self._fontsize_manipulator = FontsizeManipulator(self._view)
