Source code for pyqtgraph.parametertree.parameterTypes.slider

import numpy as np

from ...Qt import QtCore, QtWidgets
from ..Parameter import Parameter
from .basetypes import Emitter, WidgetParameterItem

[docs] class SliderParameterItem(WidgetParameterItem): slider: QtWidgets.QSlider span: np.ndarray charSpan: np.ndarray def __init__(self, param, depth): # Bind emitter to self to avoid garbage collection self.emitter = Emitter() self.sigChanging = self.emitter.sigChanging self._suffix = None super().__init__(param, depth) def updateDisplayLabel(self, value=None): if value is None: value = self.param.value() self.sliderLabel.setText(self.prettyTextValue(self.slider.value())) value = str(value) if self._suffix is None: suffixTxt = '' else: suffixTxt = f' {self._suffix}' self.displayLabel.setText(value + suffixTxt) def setSuffix(self, suffix): self._suffix = suffix # This may be called during widget construction in which case there is no # displayLabel yet if hasattr(self, 'displayLabel'): self.updateDisplayLabel(self.slider.value()) def makeWidget(self): param = self.param opts = param.opts opts.setdefault('limits', [0, 0]) self._suffix = opts.get('suffix') self.slider = QtWidgets.QSlider() self.slider.setOrientation(QtCore.Qt.Orientation.Horizontal) lbl = self.sliderLabel = QtWidgets.QLabel() lbl.setAlignment(QtCore.Qt.AlignmentFlag.AlignLeft) w = QtWidgets.QWidget() layout = QtWidgets.QHBoxLayout() w.setLayout(layout) layout.addWidget(lbl) layout.addWidget(self.slider) def setValue(v): self.slider.setValue(self.spanToSliderValue(v)) def getValue(): return self.span[self.slider.value()].item() self.slider.valueChanged.connect(self.updateDisplayLabel) def onMove(pos): self.sigChanging.emit(self, self.span[pos].item()) self.slider.sliderMoved.connect(onMove) w.setValue = setValue w.value = getValue w.sigChanged = self.slider.valueChanged w.sigChanging = self.sigChanging self.optsChanged(param, opts) return w def spanToSliderValue(self, v): return int(np.argmin(np.abs(self.span - v))) def prettyTextValue(self, v): if self._suffix is None: suffixTxt = '' else: suffixTxt = f' {self._suffix}' format_ = self.param.opts.get('format', None) cspan = self.charSpan if format_ is None: format_ = f'{{0:>{cspan.dtype.itemsize}}}{suffixTxt}' return format_.format(cspan[v].decode()) def optsChanged(self, param, opts): try: super().optsChanged(param, opts) except AttributeError: # This may trigger while building the parameter before the widget is fully constructed. # This is fine, since errors are from the parent scope which will stabilize after the widget is # constructed anyway pass span = opts.get('span', None) if span is None: step = opts.get('step', 1) start, stop = opts.get('limits', param.opts['limits']) # Add a bit to 'stop' since python slicing excludes the last value span = np.arange(start, stop + step, step) precision = opts.get('precision', 2) if precision is not None: span = span.round(precision) self.span = span self.charSpan = np.char.array(span) w = self.slider w.setMinimum(0) w.setMaximum(len(span) - 1) if 'suffix' in opts: self.setSuffix(opts['suffix']) def limitsChanged(self, param, limits): self.optsChanged(param, dict(limits=limits))
[docs] class SliderParameter(Parameter): """ ============== ======================================================== **Options** limits [start, stop] numbers step: Defaults to 1, the spacing between each slider tick span: Instead of limits + step, span can be set to specify the range of slider options (e.g. np.linspace(-pi, pi, 100)) format: Format string to determine number of decimals to show, etc. Defaults to display based on span dtype precision: int number of decimals to keep for float tick spaces ============== ======================================================== """ itemClass = SliderParameterItem