Source code for pyqtgraph.graphicsItems.LegendItem

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 PlotItem.addLegend(). Note that this item should not be added directly to a PlotItem. Instead, Make it a direct descendant of the PlotItem:: legend.setParentItem(plotItem) """
[docs] def __init__(self, size=None, offset=None): """ ============== =============================================================== **Arguments:** size Specifies the fixed size (width, height) of the legend. If this argument is omitted, the legend will autimatically 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(). ============== =============================================================== """ GraphicsWidget.__init__(self) GraphicsWidgetAnchor.__init__(self) self.setFlag(self.ItemIgnoresTransformations) self.layout = QtGui.QGraphicsGridLayout() self.setLayout(self.layout) self.items = [] self.size = size self.offset = offset if size is not None: self.setGeometry(QtCore.QRectF(0, 0, self.size[0], self.size[1]))
def setParentItem(self, p): ret = GraphicsWidget.setParentItem(self, p) if self.offset is not None: offset = Point(self.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 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) 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. ============== ======================================================== """ # Thanks, Ulrich! # cycle for a match 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
def updateSize(self): if self.size is not None: return height = 0 width = 0 #print("-------") for sample, label in self.items: height += max(sample.height(), label.height()) + 3 width = max(width, sample.width()+label.width()) #print(width, height) #print width, height self.setGeometry(0, 0, width+25, height) def boundingRect(self): return QtCore.QRectF(0, 0, self.width(), self.height()) def paint(self, p, *args): p.setPen(fn.mkPen(255,255,255,100)) p.setBrush(fn.mkBrush(100,100,100,50)) p.drawRect(self.boundingRect()) def hoverEvent(self, ev): ev.acceptDrags(QtCore.Qt.LeftButton) def mouseDragEvent(self, ev): if ev.button() == QtCore.Qt.LeftButton: 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): #p.setRenderHint(p.Antialiasing) # only if the data is antialiased. opts = self.item.opts if opts.get('fillLevel',None) is not None and opts.get('fillBrush',None) is not None: p.setBrush(fn.mkBrush(opts['fillBrush'])) p.setPen(fn.mkPen(None)) p.drawPolygon(QtGui.QPolygonF([QtCore.QPointF(2,18), QtCore.QPointF(18,2), QtCore.QPointF(18,18)])) if not isinstance(self.item, ScatterPlotItem): p.setPen(fn.mkPen(opts['pen'])) p.drawLine(2, 18, 18, 2) 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)