__all__ = ["MouseDragEvent", "MouseClickEvent", "HoverEvent"]
import weakref
from time import perf_counter
from ..Point import Point
from ..Qt import QtCore
[docs]
class MouseDragEvent(object):
"""
Instances of this class are delivered to items in a :class:`GraphicsScene <pyqtgraph.GraphicsScene>` via their mouseDragEvent() method when the item is being mouse-dragged.
"""
def __init__(self, moveEvent, pressEvent, lastEvent, start=False, finish=False):
self.start = start
self.finish = finish
self.accepted = False
self.currentItem = None
self._buttonDownScenePos = {}
self._buttonDownScreenPos = {}
for btn in [QtCore.Qt.MouseButton.LeftButton, QtCore.Qt.MouseButton.MiddleButton, QtCore.Qt.MouseButton.RightButton]:
self._buttonDownScenePos[btn] = moveEvent.buttonDownScenePos(btn)
self._buttonDownScreenPos[btn] = moveEvent.buttonDownScreenPos(btn)
self._scenePos = moveEvent.scenePos()
self._screenPos = moveEvent.screenPos()
if lastEvent is None:
self._lastScenePos = pressEvent.scenePos()
self._lastScreenPos = pressEvent.screenPos()
else:
self._lastScenePos = lastEvent.scenePos()
self._lastScreenPos = lastEvent.screenPos()
self._buttons = moveEvent.buttons()
self._button = pressEvent.button()
self._modifiers = moveEvent.modifiers()
self.acceptedItem = None
[docs]
def accept(self):
"""An item should call this method if it can handle the event. This will prevent the event being delivered to any other items."""
self.accepted = True
self.acceptedItem = self.currentItem
[docs]
def ignore(self):
"""An item should call this method if it cannot handle the event. This will allow the event to be delivered to other items."""
self.accepted = False
def isAccepted(self):
return self.accepted
[docs]
def scenePos(self):
"""Return the current scene position of the mouse."""
return Point(self._scenePos)
[docs]
def screenPos(self):
"""Return the current screen position (pixels relative to widget) of the mouse."""
return Point(self._screenPos)
[docs]
def lastScenePos(self):
"""
Return the scene position of the mouse immediately prior to this event.
"""
return Point(self._lastScenePos)
[docs]
def lastScreenPos(self):
"""
Return the screen position of the mouse immediately prior to this event.
"""
return Point(self._lastScreenPos)
[docs]
def pos(self):
"""
Return the current position of the mouse in the coordinate system of the item
that the event was delivered to.
"""
return Point(self.currentItem.mapFromScene(self._scenePos))
[docs]
def lastPos(self):
"""
Return the previous position of the mouse in the coordinate system of the item
that the event was delivered to.
"""
return Point(self.currentItem.mapFromScene(self._lastScenePos))
[docs]
def isStart(self):
"""Returns True if this event is the first since a drag was initiated."""
return self.start
[docs]
def isFinish(self):
"""Returns False if this is the last event in a drag. Note that this
event will have the same position as the previous one."""
return self.finish
def __repr__(self):
if self.currentItem is None:
lp = self._lastScenePos
p = self._scenePos
else:
lp = self.lastPos()
p = self.pos()
return "<MouseDragEvent (%g,%g)->(%g,%g) buttons=%s start=%s finish=%s>" % (lp.x(), lp.y(), p.x(), p.y(), str(self.buttons()), str(self.isStart()), str(self.isFinish()))
[docs]
def modifiers(self):
"""Return any keyboard modifiers currently pressed.
(see QGraphicsSceneMouseEvent::modifiers in the Qt documentation)
"""
return self._modifiers
[docs]
class MouseClickEvent(object):
"""
Instances of this class are delivered to items in a :class:`GraphicsScene <pyqtgraph.GraphicsScene>` via their mouseClickEvent() method when the item is clicked.
"""
def __init__(self, pressEvent, double=False):
self.accepted = False
self.currentItem = None
self._double = double
self._scenePos = pressEvent.scenePos()
self._screenPos = pressEvent.screenPos()
self._button = pressEvent.button()
self._buttons = pressEvent.buttons()
self._modifiers = pressEvent.modifiers()
self._time = perf_counter()
self.acceptedItem = None
[docs]
def accept(self):
"""An item should call this method if it can handle the event. This will prevent the event being delivered to any other items."""
self.accepted = True
self.acceptedItem = self.currentItem
[docs]
def ignore(self):
"""An item should call this method if it cannot handle the event. This will allow the event to be delivered to other items."""
self.accepted = False
def isAccepted(self):
return self.accepted
[docs]
def scenePos(self):
"""Return the current scene position of the mouse."""
return Point(self._scenePos)
[docs]
def screenPos(self):
"""Return the current screen position (pixels relative to widget) of the mouse."""
return Point(self._screenPos)
[docs]
def double(self):
"""Return True if this is a double-click."""
return self._double
[docs]
def pos(self):
"""
Return the current position of the mouse in the coordinate system of the item
that the event was delivered to.
"""
return Point(self.currentItem.mapFromScene(self._scenePos))
[docs]
def lastPos(self):
"""
Return the previous position of the mouse in the coordinate system of the item
that the event was delivered to.
"""
return Point(self.currentItem.mapFromScene(self._lastScenePos))
[docs]
def modifiers(self):
"""Return any keyboard modifiers currently pressed.
(see QGraphicsSceneMouseEvent::modifiers in the Qt documentation)
"""
return self._modifiers
def __repr__(self):
try:
if self.currentItem is None:
p = self._scenePos
else:
p = self.pos()
return "<MouseClickEvent (%g,%g) button=%s>" % (p.x(), p.y(), str(self.button()))
except:
return "<MouseClickEvent button=%s>" % (str(self.button()))
def time(self):
return self._time
[docs]
class HoverEvent(object):
"""
Instances of this class are delivered to items in a :class:`GraphicsScene <pyqtgraph.GraphicsScene>` via their hoverEvent() method when the mouse is hovering over the item.
This event class both informs items that the mouse cursor is nearby and allows items to
communicate with one another about whether each item will accept *potential* mouse events.
It is common for multiple overlapping items to receive hover events and respond by changing
their appearance. This can be misleading to the user since, in general, only one item will
respond to mouse events. To avoid this, items make calls to event.acceptClicks(button)
and/or acceptDrags(button).
Each item may make multiple calls to acceptClicks/Drags, each time for a different button.
If the method returns True, then the item is guaranteed to be
the recipient of the claimed event IF the user presses the specified mouse button before
moving. If claimEvent returns False, then this item is guaranteed NOT to get the specified
event (because another has already claimed it) and the item should change its appearance
accordingly.
event.isEnter() returns True if the mouse has just entered the item's shape;
event.isExit() returns True if the mouse has just left.
"""
def __init__(self, moveEvent, acceptable):
self.enter = False
self.acceptable = acceptable
self.exit = False
self.__clickItems = weakref.WeakValueDictionary()
self.__dragItems = weakref.WeakValueDictionary()
self.currentItem = None
if moveEvent is not None:
self._scenePos = moveEvent.scenePos()
self._screenPos = moveEvent.screenPos()
self._lastScenePos = moveEvent.lastScenePos()
self._lastScreenPos = moveEvent.lastScreenPos()
self._buttons = moveEvent.buttons()
self._modifiers = moveEvent.modifiers()
else:
self.exit = True
[docs]
def isEnter(self):
"""Returns True if the mouse has just entered the item's shape"""
return self.enter
[docs]
def isExit(self):
"""Returns True if the mouse has just exited the item's shape"""
return self.exit
[docs]
def acceptClicks(self, button):
"""Inform the scene that the item (that the event was delivered to)
would accept a mouse click event if the user were to click before
moving the mouse again.
Returns True if the request is successful, otherwise returns False (indicating
that some other item would receive an incoming click).
"""
if not self.acceptable:
return False
if button not in self.__clickItems:
self.__clickItems[button] = self.currentItem
return True
return False
[docs]
def acceptDrags(self, button):
"""Inform the scene that the item (that the event was delivered to)
would accept a mouse drag event if the user were to drag before
the next hover event.
Returns True if the request is successful, otherwise returns False (indicating
that some other item would receive an incoming drag event).
"""
if not self.acceptable:
return False
if button not in self.__dragItems:
self.__dragItems[button] = self.currentItem
return True
return False
[docs]
def scenePos(self):
"""Return the current scene position of the mouse."""
return Point(self._scenePos)
[docs]
def screenPos(self):
"""Return the current screen position of the mouse."""
return Point(self._screenPos)
[docs]
def lastScenePos(self):
"""Return the previous scene position of the mouse."""
return Point(self._lastScenePos)
[docs]
def lastScreenPos(self):
"""Return the previous screen position of the mouse."""
return Point(self._lastScreenPos)
[docs]
def pos(self):
"""
Return the current position of the mouse in the coordinate system of the item
that the event was delivered to.
"""
return Point(self.currentItem.mapFromScene(self._scenePos))
[docs]
def lastPos(self):
"""
Return the previous position of the mouse in the coordinate system of the item
that the event was delivered to.
"""
return Point(self.currentItem.mapFromScene(self._lastScenePos))
def __repr__(self):
if self.exit:
return "<HoverEvent exit=True>"
if self.currentItem is None:
lp = self._lastScenePos
p = self._scenePos
else:
lp = self.lastPos()
p = self.pos()
return "<HoverEvent (%g,%g)->(%g,%g) buttons=%s enter=%s exit=%s>" % (lp.x(), lp.y(), p.x(), p.y(), str(self.buttons()), str(self.isEnter()), str(self.isExit()))
[docs]
def modifiers(self):
"""Return any keyboard modifiers currently pressed.
(see QGraphicsSceneMouseEvent::modifiers in the Qt documentation)
"""
return self._modifiers
def clickItems(self):
return self.__clickItems
def dragItems(self):
return self.__dragItems