def __init__(self, image=None, fillHistogram=True):
"""
If *image* (ImageItem) is provided, then the control will be automatically linked to the image and changes to the control will be immediately reflected in the image's appearance.
By default, the histogram is rendered with a fill. For performance, set *fillHistogram* = False.
"""
GraphicsWidget.__init__(self)
self.lut = None
self.imageItem = None
self.layout = QtGui.QGraphicsGridLayout()
self.setLayout(self.layout)
self.layout.setContentsMargins(1, 1, 1, 1)
self.layout.setSpacing(0)
self.vb = ViewBox()
self.vb.setMaximumWidth(152)
self.vb.setMinimumWidth(52)
self.vb.setMouseEnabled(x=False, y=True)
self.gradient = GradientEditorItem()
self.gradient.setOrientation('right')
self.gradient.loadPreset('grey')
self.region = LinearRegionItem([0, 1], LinearRegionItem.Horizontal)
self.region.setZValue(1000)
self.vb.addItem(self.region)
self.axis = AxisItem('left',
linkView=self.vb,
maxTickLength=-10,
showValues=False)
self.layout.addItem(self.axis, 0, 0)
self.layout.addItem(self.vb, 0, 1)
self.layout.addItem(self.gradient, 0, 2)
self.range = None
self.gradient.setFlag(self.gradient.ItemStacksBehindParent)
self.vb.setFlag(self.gradient.ItemStacksBehindParent)
#self.grid = GridItem()
#self.vb.addItem(self.grid)
self.gradient.sigGradientChanged.connect(self.gradientChanged)
self.region.sigRegionChanged.connect(self.regionChanging)
self.region.sigRegionChangeFinished.connect(self.regionChanged)
self.vb.sigRangeChanged.connect(self.viewRangeChanged)
self.plot = PlotDataItem()
self.plot.rotate(90)
self.fillHistogram(fillHistogram)
self.vb.addItem(self.plot)
self.autoHistogramRange()
if image is not None:
self.setImageItem(image)
