def init( self, component, bounds_rect, anchor, unconstrain,
drag_event, start_event ):
self.component = component
self.bounds_rect = bounds_rect
self.anchor = anchor
self.unconstrain = unconstrain
self.drag_event = drag_event
self.start_event = start_event
self.drag_x = self.start_x = start_event.x
self.drag_y = self.start_y = start_event.y
# Get the coordinates of the anchor point:
xl, yb, xr, yt = bounds_to_coordinates( component.bounds )
if (anchor & LEFT) != 0:
self.anchor_x = xl
self.float_x = xr
else:
self.anchor_x = xr
self.float_x = xl
if (anchor & BOTTOM) != 0:
self.anchor_y = yb
self.float_y = yt
else:
self.anchor_y = yt
self.float_y = yb
# Set up the drag termination handler:
self.on_trait_change( self.drag_done, drag_event )
def _mouse_move_changed ( self, event ):
# Get the current drag location:
x = event.x
y = event.y
# If the mouse did not actually move, then ignore the event:
if (x == self.drag_x) and (y == self.drag_y):
return
# Save the new position:
self.drag_x = x
self.drag_y = y
# Calculate the distance moved from the original starting point:
dx = x - self.start_x
dy = y - self.start_y
# Calculate the new drag bounds:
xl, yb, xr, yt = add_rectangles( self.drag_bounds_rect_start,
( dx, dy, dx, dy ) )
# Adjust the new drag location if it is not completely within the drag
# bounds. Exit if the result is the same as the previous location:
if self.bounds_rect is not None:
bxl, byb, bxr, byt = self.bounds_rect
if xl < bxl:
xr += bxl - xl
xl = bxl
elif xr > bxr:
xl -= xr - bxr
xr = bxr
if yb < byb:
yt += byb - yb
yb = byb
elif yt > byt:
yb -= yt - byt
yt = byt
x = xl - self.drag_bounds_rect[0] + self.drag_x
y = yb - self.drag_bounds_rect[1] + self.drag_y
# If the new drag bounds is the same as the last one, nothing changed:
drag_bounds_rect = bounds_to_coordinates( self.drag_validate( event,
( xl, yb, xr - xl, yt - yb ) ) )
if drag_bounds_rect == self.drag_bounds_rect:
return
# Update the drag bounds and current drag location:
self.drag_bounds_rect = drag_bounds_rect
# Notify each drag component of its new drag location:
dx = drag_bounds_rect[0] - self.drag_bounds_rect_start[0]
dy = drag_bounds_rect[1] - self.drag_bounds_rect_start[1]
for component in self.components:
cx, cy = component.location()
component.dragged = DragEvent( x = cx + dx,
y = cy + dy,
x0 = self.start_x,
y0 = self.start_y,
copy = self.drag_copy,
components = self.components,
start_event = self.start_event,
window = event.window )
# Process the 'drag_over' events for any objects being dragged over:
drag_over_event = DragEvent( x = x,
y = y,
x0 = self.start_x,
y0 = self.start_y,
copy = self.drag_copy,
components = self.components,
start_event = self.start_event,
window = event.window )
new_drag_over = []
cur_drag_over = self.drag_over
for component in self.drag_root.components_at( x, y ):
new_drag_over.append( component )
if component in cur_drag_over:
cur_drag_over.remove( component )
component.drag_over = drag_over_event
else:
component.drag_enter = drag_over_event
for component in cur_drag_over:
component.drag_leave = drag_over_event
self.drag_over = new_drag_over
# Tell the Enable window where the drag is now:
self.window.set_drag_bounds_rect( drag_bounds_rect )
def drag_done ( self, event ):
components = self.components
drag_copy = self.drag_copy
start_event = self.start_event
# 'Unhook' the drag done notification handler:
self.on_trait_change( self.drag_done, self.drag_event, remove = True )
# Compute the new drag bounds:
x = event.x
y = event.y
dx = x - self.start_x
dy = y - self.start_y
xl, yb, xr, yt = add_rectangles( self.drag_bounds_rect_start,
( dx, dy, dx, dy ) )
drag_bounds_rect = bounds_to_coordinates( self.drag_validate( event,
( xl, yb, xr - xl, yt - yb ) ) )
# If the new bounds are not within the drag area, use the last drag
# location:
if ((self.bounds_rect is not None) and
(intersect_coordinates( self.bounds_rect, drag_bounds_rect ) !=
drag_bounds_rect)):
drag_bounds_rect = self.drag_bounds_rect
# Notify each dragged component where it was dropped:
dx = drag_bounds_rect[0] - self.drag_bounds_rect_start[0]
dy = drag_bounds_rect[1] - self.drag_bounds_rect_start[1]
for component in components:
cx, cy = component.location()
component.dropped = DragEvent( x = cx + dx,
y = cy + dy,
x0 = self.start_x,
y0 = self.start_y,
copy = drag_copy,
components = components,
start_event = start_event,
window = event.window )
# Process the 'dropped_on' event for the object(s) it was dropped on:
components_at = self.drag_root.components_at( x, y )
drag_event = DragEvent( x = self.start_x + dx,
y = self.start_y + dy,
x0 = self.start_x,
y0 = self.start_y,
copy = drag_copy,
components = components,
start_event = start_event,
window = event.window )
index = send_event_to( components_at, 'dropped_on', drag_event )
# Send all the runner-ups a 'drag_leave' consolation prize:
drag_over = self.drag_over
for component in components_at[ 0: index ]:
if component in drag_over:
component.drag_leave = drag_event
# Make sure all of the dragged components are drawable again:
if not drag_copy:
for component in components:
component._drawable = True
# Redraw the window to clean-up any drag artifacts:
self.window.redraw()
# Finally, release any references we have been using:
self.components[:] = []
self.drag_over = self.drag_root = self.window = None
def _needs_redraw(self, bounds):
"Determine if a specified region intersects the update region"
return does_disjoint_intersect_coordinates( self._update_region,
bounds_to_coordinates( bounds ) )
