# -*- coding: utf-8 -*-
from .GraphicsWidget import GraphicsWidget
from .LabelItem import LabelItem
from ..Qt import QtGui, QtCore
from .. import functions as fn
from ..Point import Point
from .ScatterPlotItem import ScatterPlotItem, drawSymbol
from .PlotDataItem import PlotDataItem
from .GraphicsWidgetAnchor import GraphicsWidgetAnchor
__all__ = ['LegendItem']
[docs]class LegendItem(GraphicsWidget, GraphicsWidgetAnchor):
"""
Displays a legend used for describing the contents of a plot.
LegendItems are most commonly created by calling :meth:`PlotItem.addLegend
<pyqtgraph.PlotItem.addLegend>`.
Note that this item should *not* be added directly to a PlotItem (via
:meth:`PlotItem.addItem <pyqtgraph.PlotItem.addItem>`). Instead, make it a
direct descendant of the PlotItem::
legend.setParentItem(plotItem)
"""
[docs] def __init__(self, size=None, offset=None, horSpacing=25, verSpacing=0, pen=None,
brush=None, labelTextColor=None, **kwargs):
"""
============== ===============================================================
**Arguments:**
size Specifies the fixed size (width, height) of the legend. If
this argument is omitted, the legend will automatically resize
to fit its contents.
offset Specifies the offset position relative to the legend's parent.
Positive values offset from the left or top; negative values
offset from the right or bottom. If offset is None, the
legend must be anchored manually by calling anchor() or
positioned by calling setPos().
horSpacing Specifies the spacing between the line symbol and the label.
verSpacing Specifies the spacing between individual entries of the legend
vertically. (Can also be negative to have them really close)
pen Pen to use when drawing legend border. Any single argument
accepted by :func:`mkPen <pyqtgraph.mkPen>` is allowed.
brush QBrush to use as legend background filling. Any single argument
accepted by :func:`mkBrush <pyqtgraph.mkBrush>` is allowed.
labelTextColor Pen to use when drawing legend text. Any single argument
accepted by :func:`mkPen <pyqtgraph.mkPen>` is allowed.
============== ===============================================================
"""
GraphicsWidget.__init__(self)
GraphicsWidgetAnchor.__init__(self)
self.setFlag(self.ItemIgnoresTransformations)
self.layout = QtGui.QGraphicsGridLayout()
self.layout.setVerticalSpacing(verSpacing)
self.layout.setHorizontalSpacing(horSpacing)
self.setLayout(self.layout)
self.items = []
self.size = size
if size is not None:
self.setGeometry(QtCore.QRectF(0, 0, self.size[0], self.size[1]))
self.opts = {
'pen': fn.mkPen(pen),
'brush': fn.mkBrush(brush),
'labelTextColor': labelTextColor,
'offset': offset,
}
self.opts.update(kwargs)
[docs] def offset(self):
"""Get the offset position relative to the parent."""
return self.opts['offset']
[docs] def setOffset(self, offset):
"""Set the offset position relative to the parent."""
self.opts['offset'] = offset
offset = Point(self.opts['offset'])
anchorx = 1 if offset[0] <= 0 else 0
anchory = 1 if offset[1] <= 0 else 0
anchor = (anchorx, anchory)
self.anchor(itemPos=anchor, parentPos=anchor, offset=offset)
[docs] def pen(self):
"""Get the QPen used to draw the border around the legend."""
return self.opts['pen']
[docs] def setPen(self, *args, **kargs):
"""Set the pen used to draw a border around the legend.
Accepts the same arguments as :func:`~pyqtgraph.mkPen`.
"""
pen = fn.mkPen(*args, **kargs)
self.opts['pen'] = pen
self.update()
[docs] def brush(self):
"""Get the QBrush used to draw the legend background."""
return self.opts['brush']
[docs] def setBrush(self, *args, **kargs):
"""Set the brush used to draw the legend background.
Accepts the same arguments as :func:`~pyqtgraph.mkBrush`.
"""
brush = fn.mkBrush(*args, **kargs)
if self.opts['brush'] == brush:
return
self.opts['brush'] = brush
self.update()
[docs] def labelTextColor(self):
"""Get the QColor used for the item labels."""
return self.opts['labelTextColor']
[docs] def setLabelTextColor(self, *args, **kargs):
"""Set the color of the item labels.
Accepts the same arguments as :func:`~pyqtgraph.mkColor`.
"""
self.opts['labelTextColor'] = fn.mkColor(*args, **kargs)
for sample, label in self.items:
label.setAttr('color', self.opts['labelTextColor'])
self.update()
[docs] def setParentItem(self, p):
"""Set the parent."""
ret = GraphicsWidget.setParentItem(self, p)
if self.opts['offset'] is not None:
offset = Point(self.opts['offset'])
anchorx = 1 if offset[0] <= 0 else 0
anchory = 1 if offset[1] <= 0 else 0
anchor = (anchorx, anchory)
self.anchor(itemPos=anchor, parentPos=anchor, offset=offset)
return ret
[docs] def addItem(self, item, name):
"""
Add a new entry to the legend.
============== ========================================================
**Arguments:**
item A :class:`~pyqtgraph.PlotDataItem` from which the line
and point style of the item will be determined or an
instance of ItemSample (or a subclass), allowing the
item display to be customized.
title The title to display for this item. Simple HTML allowed.
============== ========================================================
"""
label = LabelItem(name, color=self.opts['labelTextColor'], justify='left')
if isinstance(item, ItemSample):
sample = item
else:
sample = ItemSample(item)
row = self.layout.rowCount()
self.items.append((sample, label))
self.layout.addItem(sample, row, 0)
self.layout.addItem(label, row, 1)
self.updateSize()
[docs] def removeItem(self, item):
"""
Removes one item from the legend.
============== ========================================================
**Arguments:**
item The item to remove or its name.
============== ========================================================
"""
for sample, label in self.items:
if sample.item is item or label.text == item:
self.items.remove((sample, label)) # remove from itemlist
self.layout.removeItem(sample) # remove from layout
sample.close() # remove from drawing
self.layout.removeItem(label)
label.close()
self.updateSize() # redraq box
return # return after first match
[docs] def clear(self):
"""Remove all items from the legend."""
for sample, label in self.items:
self.layout.removeItem(sample)
self.layout.removeItem(label)
self.items = []
self.updateSize()
def updateSize(self):
if self.size is not None:
return
self.setGeometry(0, 0, 0, 0)
def boundingRect(self):
return QtCore.QRectF(0, 0, self.width(), self.height())
def paint(self, p, *args):
p.setPen(self.opts['pen'])
p.setBrush(self.opts['brush'])
p.drawRect(self.boundingRect())
def hoverEvent(self, ev):
ev.acceptDrags(QtCore.Qt.LeftButton)
def mouseDragEvent(self, ev):
if ev.button() == QtCore.Qt.LeftButton:
ev.accept()
dpos = ev.pos() - ev.lastPos()
self.autoAnchor(self.pos() + dpos)
class ItemSample(GraphicsWidget):
""" Class responsible for drawing a single item in a LegendItem (sans label).
This may be subclassed to draw custom graphics in a Legend.
"""
## Todo: make this more generic; let each item decide how it should be represented.
def __init__(self, item):
GraphicsWidget.__init__(self)
self.item = item
def boundingRect(self):
return QtCore.QRectF(0, 0, 20, 20)
def paint(self, p, *args):
opts = self.item.opts
if opts.get('antialias'):
p.setRenderHint(p.Antialiasing)
if not isinstance(self.item, ScatterPlotItem):
p.setPen(fn.mkPen(opts['pen']))
p.drawLine(0, 11, 20, 11)
symbol = opts.get('symbol', None)
if symbol is not None:
if isinstance(self.item, PlotDataItem):
opts = self.item.scatter.opts
pen = fn.mkPen(opts['pen'])
brush = fn.mkBrush(opts['brush'])
size = opts['size']
p.translate(10, 10)
path = drawSymbol(p, symbol, size, pen, brush)