Source code for pyqtgraph.graphicsItems.LegendItem

import math

from .. import functions as fn
from ..icons import invisibleEye
from ..Point import Point
from ..Qt import QtCore, QtGui, QtWidgets
from .BarGraphItem import BarGraphItem
from .GraphicsWidget import GraphicsWidget
from .GraphicsWidgetAnchor import GraphicsWidgetAnchor
from .LabelItem import LabelItem
from .PlotDataItem import PlotDataItem
from .ScatterPlotItem import ScatterPlotItem, drawSymbol

__all__ = ['LegendItem', 'ItemSample']

[docs] class LegendItem(GraphicsWidgetAnchor, GraphicsWidget): """ 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, frame=True, labelTextSize='9pt', colCount=1, sampleType=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. labelTextSize Size to use when drawing legend text. Accepts CSS style string arguments, e.g. '9pt'. colCount Specifies the integer number of columns that the legend should be divided into. The number of rows will be calculated based on this argument. This is useful for plots with many curves displayed simultaneously. Default: 1 column. sampleType Customizes the item sample class of the `LegendItem`. ============== =============================================================== """ GraphicsWidget.__init__(self) GraphicsWidgetAnchor.__init__(self) self.setFlag(self.GraphicsItemFlag.ItemIgnoresTransformations) self.layout = QtWidgets.QGraphicsGridLayout() self.layout.setVerticalSpacing(verSpacing) self.layout.setHorizontalSpacing(horSpacing) self.setLayout(self.layout) self.items = [] self.size = size self.offset = offset self.frame = frame self.columnCount = colCount self.rowCount = 1 if size is not None: self.setGeometry(QtCore.QRectF(0, 0, self.size[0], self.size[1])) if sampleType is not None: if not issubclass(sampleType, GraphicsWidget): raise RuntimeError("Only classes of type `GraphicsWidgets` " "are allowed as `sampleType`") self.sampleType = sampleType else: self.sampleType = ItemSample self.opts = { 'pen': fn.mkPen(pen), 'brush': fn.mkBrush(brush), 'labelTextColor': labelTextColor, 'labelTextSize': labelTextSize, 'offset': offset, } self.opts.update(kwargs)
[docs] def setSampleType(self, sample): """Set the new sample item claspes""" if sample is self.sampleType: return # Clear the legend, but before create a list of items items = list(self.items) self.sampleType = sample self.clear() # Refill the legend with the item list and new sample item for sample, label in items: plot_item = sample.item plot_name = label.text self.addItem(plot_item, plot_name) self.updateSize()
[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 labelTextSize(self): """Get the `labelTextSize` used for the item labels.""" return self.opts['labelTextSize']
[docs] def setLabelTextSize(self, size): """Set the `size` of the item labels. Accepts the CSS style string arguments, e.g. '8pt'. """ self.opts['labelTextSize'] = size for _, label in self.items: label.setAttr('size', self.opts['labelTextSize']) 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', size=self.opts['labelTextSize']) if isinstance(item, self.sampleType): sample = item else: sample = self.sampleType(item) self.items.append((sample, label)) self._addItemToLayout(sample, label) self.updateSize()
def _addItemToLayout(self, sample, label): col = self.layout.columnCount() row = self.layout.rowCount() if row: row -= 1 nCol = self.columnCount * 2 # FIRST ROW FULL if col == nCol: for col in range(0, nCol, 2): # FIND RIGHT COLUMN if not self.layout.itemAt(row, col): break else: if col + 2 == nCol: # MAKE NEW ROW col = 0 row += 1 self.layout.addItem(sample, row, col) self.layout.addItem(label, row, col + 1) # Keep rowCount in sync with the number of rows if items are added self.rowCount = max(self.rowCount, row + 1)
[docs] def setColumnCount(self, columnCount): """change the orientation of all items of the legend """ if columnCount != self.columnCount: self.columnCount = columnCount self.rowCount = math.ceil(len(self.items) / columnCount) for i in range(self.layout.count() - 1, -1, -1): self.layout.removeAt(i) # clear layout for sample, label in self.items: self._addItemToLayout(sample, label) self.updateSize()
[docs] def getLabel(self, plotItem): """Return the labelItem inside the legend for a given plotItem The label-text can be changed via labelItem.setText """ out = [(it, lab) for it, lab in self.items if it.item == plotItem] try: return out[0][1] except IndexError: return None
def _removeItemFromLayout(self, *args): for item in args: self.layout.removeItem(item) item.close() # Normally, the item is automatically removed from # its scene when it gets destroyed. # this doesn't happen on current versions of # PySide (5.15.x, 6.3.x) and results in a leak. scene = item.scene() if scene: scene.removeItem(item)
[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._removeItemFromLayout(sample, label) self.updateSize() # redraw box return # return after first match
[docs] def clear(self): """Remove all items from the legend.""" for sample, label in self.items: self._removeItemFromLayout(sample, label) self.items = [] self.updateSize()
def updateSize(self): if self.size is not None: return height = 0 width = 0 for row in range(self.layout.rowCount()): row_height = 0 col_width = 0 for col in range(self.layout.columnCount()): item = self.layout.itemAt(row, col) if item: col_width += item.width() + 3 row_height = max(row_height, item.height()) width = max(width, col_width) height += row_height self.setGeometry(0, 0, width, height) return def boundingRect(self): return QtCore.QRectF(0, 0, self.width(), self.height()) def paint(self, p, *args): if self.frame: p.setPen(self.opts['pen']) p.setBrush(self.opts['brush']) p.drawRect(self.boundingRect()) def hoverEvent(self, ev): ev.acceptDrags(QtCore.Qt.MouseButton.LeftButton) def mouseDragEvent(self, ev): if ev.button() == QtCore.Qt.MouseButton.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) """ 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.RenderHint.Antialiasing) visible = self.item.isVisible() if not visible: icon = invisibleEye.qicon p.drawPixmap(QtCore.QPoint(1, 1), icon.pixmap(18, 18)) return if not isinstance(self.item, ScatterPlotItem): p.setPen(fn.mkPen(opts['pen'])) p.drawLine(0, 11, 20, 11) 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(opts['pen'])) p.drawPolygon(QtGui.QPolygonF( [QtCore.QPointF(2, 18), QtCore.QPointF(18, 2), QtCore.QPointF(18, 18)])) symbol = opts.get('symbol', None) if symbol is not None: if isinstance(self.item, PlotDataItem): opts = self.item.scatter.opts p.translate(10, 10) drawSymbol(p, symbol, opts['size'], fn.mkPen(opts['pen']), fn.mkBrush(opts['brush'])) if isinstance(self.item, BarGraphItem): p.setBrush(fn.mkBrush(opts['brush'])) p.drawRect(QtCore.QRectF(2, 2, 18, 18)) def mouseClickEvent(self, event): """Use the mouseClick event to toggle the visibility of the plotItem """ if event.button() == QtCore.Qt.MouseButton.LeftButton: visible = self.item.isVisible() self.item.setVisible(not visible) event.accept() self.update()