问题描述
在pyqtgraph examples -> View Box Freatures中，我们可以通过设置v2.setMouseMode(v2.RectMode)
但是此交互仅在一键鼠标模式下可用。我如何修改交互，以便我可以在标准三键鼠标模式下使用鼠标右键或鼠标中键缩放到选定的框？
谢谢大家！
解决方法
ViewBox 的 pyqtgraph 类只有两种“鼠标模式”：
- PanMode：鼠标左键和中键用于拖动。鼠标右键可通过拖动放大/缩小。
- RectMode：鼠标左键和中键用于缩放框。鼠标右键可通过拖动放大/缩小。
Left 和 Middle 鼠标工作相同的原因在于 ViewBox 类的源代码。
您希望鼠标左键拖动图片，鼠标中键缩放框，鼠标中键缩放框以通过拖动放大/缩小。我的解决方案可能是激进的，但它有效。我修改了类，使用源代码作为模型（来源：Pyqtgraph's ViewBox class）：
import pyqtgraph as pg
from pyqtgraph.Qt import QtCore,QtGui
import numpy as np
class ViewBox(pg.ViewBox):
MyMode = 2
def __init__(self):
pg.ViewBox.__init__(self)
def setMouseMode(self,mode):
## First we change this method to accept our new configuration
if mode not in [ViewBox.PanMode,ViewBox.RectMode,ViewBox.MyMode]:
raise Exception("Mode must be ViewBox.PanMode,ViewBox.RectMode or ViewBox.MyMode")
self.state['mouseMode'] = mode
self.sigStateChanged.emit(self)
def mouseDragEvent(self,ev,axis=None):
ev.accept()
pos = ev.pos()
lastPos = ev.lastPos()
dif = pos - lastPos
dif = dif * -1
mouseEnabled = np.array(self.state['mouseEnabled'],dtype=np.float)
mask = mouseEnabled.copy()
if axis is not None:
mask[1-axis] = 0.0
## Here is the main change for it to work
if ev.button() & QtCore.Qt.LeftButton:
if self.state['mouseMode'] == ViewBox.RectMode and axis is None:
if ev.isFinish(): ## This is the final move in the drag; change the view scale now
#print "finish"
self.rbScaleBox.hide()
ax = QtCore.QRectF(QtCore.QPointF(ev.buttonDownPos(ev.button())),QtCore.QPointF(pos))
ax = self.childGroup.mapRectFromParent(ax)
self.showAxRect(ax)
self.axHistoryPointer += 1
self.axHistory = self.axHistory[:self.axHistoryPointer] + [ax]
else:
## update shape of scale box
self.updateScaleBox(ev.buttonDownPos(),ev.pos())
else:
tr = self.childGroup.transform()
tr = pg.functions.invertQTransform(tr)
tr = tr.map(dif*mask) - tr.map(QtCore.QPointF(0,0))
x = tr.x() if mask[0] == 1 else None
y = tr.y() if mask[1] == 1 else None
self._resetTarget()
if x is not None or y is not None:
self.translateBy(x=x,y=y)
self.sigRangeChangedManually.emit(self.state['mouseEnabled'])
elif ev.button() & QtCore.Qt.MidButton:
if self.state['mouseMode'] in {ViewBox.RectMode,ViewBox.MyMode} and axis is None:
if ev.isFinish(): ## This is the final move in the drag; change the view scale now
#print "finish"
self.rbScaleBox.hide()
ax = QtCore.QRectF(QtCore.QPointF(ev.buttonDownPos(ev.button())),y=y)
self.sigRangeChangedManually.emit(self.state['mouseEnabled'])
elif ev.button() & QtCore.Qt.RightButton:
if self.state['aspectLocked'] is not False:
mask[0] = 0
dif = ev.screenPos() - ev.lastScreenPos()
dif = np.array([dif.x(),dif.y()])
dif[0] *= -1
s = ((mask * 0.02) + 1) ** dif
tr = self.childGroup.transform()
tr = pg.functions.invertQTransform(tr)
x = s[0] if mouseEnabled[0] == 1 else None
y = s[1] if mouseEnabled[1] == 1 else None
center = QtCore.QPointF(tr.map(ev.buttonDownPos(QtCore.Qt.RightButton)))
self._resetTarget()
self.scaleBy(x=x,y=y,center=center)
self.sigRangeChangedManually.emit(self.state['mouseEnabled'])
我们继承了Pyqtgraph的ViewBox类，然后改了两个方法：
-
setMouseMode()兼容性 -
mouseDragEvent用于 3 次点击的不同功能
在上面的类中，您保持其他两种鼠标模式不变，但添加了一个新模式：MyMode。
然后，而不是像这样添加 ViewBox ：
sub2 = win.addLayout()
sub2.addLabel("<b>One-button mouse interaction:</b><br>left-drag zoom to box,wheel to zoom out.")
sub2.nextRow()
v2 = sub2.addViewBox()
v2.setMouseMode(v2.RectMode)
l2 = pg.PlotDataItem(y)
v2.addItem(l2)
你应该这样做：
sub2 = win.addLayout()
sub2.addLabel("<b>One-button mouse interaction:</b><br>left-drag zoom to box,wheel to zoom out.")
sub2.nextRow()
v2 = ViewBox() ## This is our new class
sub2.addItem(v2)
v2.setMouseMode(v2.MyMode) ## Seting the new Mouse Mode
l2 = pg.PlotDataItem(y)
v2.addItem(l2)
我测试了代码并没有发现任何问题，但我不得不承认解决方案有点夸张。希望有更简单的方法。
编辑：示例取自 Pyqtgraph 的示例（ViewBox 功能）(Here)