Question

我在两个小部件（两个按钮）之间绘制一条线，将它们的位置作为参考。但这条线是在错误的地方绘制的。

我尝试使用mapToGlobal或mapToParent这样的功能，但效果不同，但仍然存在问题。在同一个类中，我有另一种用鼠标绘制线条的方法，它可以正常工作。我把它当作参考，但似乎事件位置有一个不同的坐标系。我不知道为什么会这样。

按钮和图形视图位于窗口小部件内，窗口小部件也在窗口内。

这是班级：

from PyQt4 import QtGui, QtCore

class WiringGraphicsView(QtGui.QGraphicsView):

    def __init__(self, parent):
        QtGui.QGraphicsView.__init__(self, parent)
        self.setScene(QtGui.QGraphicsScene(self))
        #self.setSceneRect(QtCore.QRectF(self.viewport().rect()))

    def mousePressEvent(self, event):
        self._start = event.pos()

    def mouseReleaseEvent(self, event):
        start = QtCore.QPointF(self.mapToScene(self._start))
        end = QtCore.QPointF(self.mapToScene(event.pos()))
        brush = QtGui.QBrush(QtGui.QColor(255, 0, 0) )
        pen = QtGui.QPen(brush, 2)
        line = QtGui.QGraphicsLineItem(QtCore.QLineF(start, end))
        line.setPen(pen)
        self.scene().addItem( line )

    def paintWire(self, start_widget,  end_widget):
        start_position = QtCore.QPointF(self.mapToScene(start_widget.pos()))
        end_position = QtCore.QPointF(self.mapToScene(end_widget.pos()))
        brush = QtGui.QBrush(QtGui.QColor(255, 0, 0) )
        pen = QtGui.QPen(brush, 2)
        line = QtGui.QGraphicsLineItem(QtCore.QLineF(start_position, end_position))
        line.setPen(pen)
        self.scene().addItem( line )

Current Drawing

更新：此时我已经尝试了几件事：由于按钮包含在QWidget对象中，我从那里取出它们。我把它们放在GroupBox中。也试过没有容器。我没有得到满意的结果。老实说，考虑到我使用Qt设计器并为＃34;提升＆＃34;创建类文件，我不知道如何正确地做到这一点。小部件（在本例中为GraphicsView）并使用主文件中的UpdateUi方法设置一些属性

更新2：这是加载应用程序的文件：

from PyQt4.QtCore import *
from PyQt4.QtGui import *
import ui_wolfsonmixerwindow

class WolfsonMixerWindow(QMainWindow, ui_wolfsonmixerwindow.Ui_WolfsonMixerWindow):

      def __init__(self,  parent=None):
         super(WolfsonMixerWindow,  self).__init__(parent)
         self.setupUi(self)
         self.updateUi()


      def updateUi(self):
          #self.btn_AIF1RX1.setText("Hola")

          menu_plugin = QMenu()
          menu_unplug = QMenu()

          menu_plugin.addAction('Action 1', self.plugin )
          self.btn_AIF1RX1_2.setMenu(menu_plugin)

          self.btn_AIF1TX1_5.setAllowDrag(False)
          self.btn_AIF1TX1_5.setMenu(menu_unplug)



          start = self.btn_AIF1RX1_2
          end = self.btn_AIF1TX1_5

          #self.graphicsView.scene().addWidget(self.btn_AIF1RX1_2)
          #self.graphicsView.scene().addWidget(self.btn_AIF1TX1_5)
          #self.graphicsView.setWidgets(start, end)

           #HERE I CALL THE PAINTWIRE METHOD
          self.graphicsView.paintWire(start, end)


if __name__ == "__main__":
  import sys
  app = QApplication(sys.argv)
  form = WolfsonMixerWindow()
  form.show()
  app.exec_()

和uic文件：

# -*- coding: utf-8 -*-

# Form implementation generated from reading ui file 'ui_wolfsonmixerwindow.ui'
#
# Created: Thu Feb 19 21:51:35 2015
#      by: PyQt4 UI code generator 4.11.3
#
# WARNING! All changes made in this file will be lost!

from PyQt4 import QtCore, QtGui

try:
    _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
    def _fromUtf8(s):
        return s

try:
    _encoding = QtGui.QApplication.UnicodeUTF8
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig, _encoding)
except AttributeError:
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig)

class Ui_WolfsonMixerWindow(object):
    def setupUi(self, WolfsonMixerWindow):
        WolfsonMixerWindow.setObjectName(_fromUtf8("WolfsonMixerWindow"))
        WolfsonMixerWindow.resize(562, 480)
        self.centralwidget = QtGui.QWidget(WolfsonMixerWindow)
        self.centralwidget.setObjectName(_fromUtf8("centralwidget"))
        self.gridLayoutWidget = QtGui.QWidget(self.centralwidget)
        self.gridLayoutWidget.setGeometry(QtCore.QRect(200, 10, 241, 101))
        self.gridLayoutWidget.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.gridLayoutWidget.setObjectName(_fromUtf8("gridLayoutWidget"))
        self.gridLayout = QtGui.QGridLayout(self.gridLayoutWidget)
        self.gridLayout.setSizeConstraint(QtGui.QLayout.SetMaximumSize)
        self.gridLayout.setMargin(0)
        self.gridLayout.setObjectName(_fromUtf8("gridLayout"))
        self.QHBox_Playback = QtGui.QHBoxLayout()
        self.QHBox_Playback.setObjectName(_fromUtf8("QHBox_Playback"))
        self.verticalLayout = QtGui.QVBoxLayout()
        self.verticalLayout.setObjectName(_fromUtf8("verticalLayout"))
        self.label_2 = QtGui.QLabel(self.gridLayoutWidget)
        self.label_2.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.label_2.setAlignment(QtCore.Qt.AlignCenter)
        self.label_2.setObjectName(_fromUtf8("label_2"))
        self.verticalLayout.addWidget(self.label_2)
        self.label = QtGui.QLabel(self.gridLayoutWidget)
        self.label.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.label.setAlignment(QtCore.Qt.AlignCenter)
        self.label.setObjectName(_fromUtf8("label"))
        self.verticalLayout.addWidget(self.label)
        self.btn_AIF1RX1 = DragButton(self.gridLayoutWidget)
        self.btn_AIF1RX1.setBaseSize(QtCore.QSize(0, 0))
        self.btn_AIF1RX1.setMouseTracking(True)
        self.btn_AIF1RX1.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.btn_AIF1RX1.setText(_fromUtf8(""))
        icon = QtGui.QIcon()
        icon.addPixmap(QtGui.QPixmap(_fromUtf8(":/audio-input-line.png")), QtGui.QIcon.Normal, QtGui.QIcon.Off)
        self.btn_AIF1RX1.setIcon(icon)
        self.btn_AIF1RX1.setAutoDefault(False)
        self.btn_AIF1RX1.setDefault(False)
        self.btn_AIF1RX1.setFlat(True)
        self.btn_AIF1RX1.setObjectName(_fromUtf8("btn_AIF1RX1"))
        self.verticalLayout.addWidget(self.btn_AIF1RX1)
        self.QHBox_Playback.addLayout(self.verticalLayout)
        self.verticalLayout_2 = QtGui.QVBoxLayout()
        self.verticalLayout_2.setObjectName(_fromUtf8("verticalLayout_2"))
        self.label_3 = QtGui.QLabel(self.gridLayoutWidget)
        self.label_3.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.label_3.setAlignment(QtCore.Qt.AlignCenter)
        self.label_3.setObjectName(_fromUtf8("label_3"))
        self.verticalLayout_2.addWidget(self.label_3)
        self.label_4 = QtGui.QLabel(self.gridLayoutWidget)
        self.label_4.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.label_4.setAlignment(QtCore.Qt.AlignCenter)
        self.label_4.setObjectName(_fromUtf8("label_4"))
        self.verticalLayout_2.addWidget(self.label_4)
        self.btn_AIF1RX2 = QtGui.QPushButton(self.gridLayoutWidget)
        self.btn_AIF1RX2.setBaseSize(QtCore.QSize(0, 0))
        self.btn_AIF1RX2.setMouseTracking(True)
        self.btn_AIF1RX2.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.btn_AIF1RX2.setText(_fromUtf8(""))
        self.btn_AIF1RX2.setIcon(icon)
        self.btn_AIF1RX2.setAutoDefault(False)
        self.btn_AIF1RX2.setDefault(False)
        self.btn_AIF1RX2.setFlat(True)
        self.btn_AIF1RX2.setObjectName(_fromUtf8("btn_AIF1RX2"))
        self.verticalLayout_2.addWidget(self.btn_AIF1RX2)
        self.QHBox_Playback.addLayout(self.verticalLayout_2)
        self.gridLayout.addLayout(self.QHBox_Playback, 1, 0, 1, 1)
        self.horizontalLayout_3 = QtGui.QHBoxLayout()
        self.horizontalLayout_3.setSizeConstraint(QtGui.QLayout.SetDefaultConstraint)
        self.horizontalLayout_3.setContentsMargins(-1, -1, 0, -1)
        self.horizontalLayout_3.setObjectName(_fromUtf8("horizontalLayout_3"))
        self.verticalLayout_3 = QtGui.QVBoxLayout()
        self.verticalLayout_3.setObjectName(_fromUtf8("verticalLayout_3"))
        self.label_6 = QtGui.QLabel(self.gridLayoutWidget)
        self.label_6.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.label_6.setAlignment(QtCore.Qt.AlignCenter)
        self.label_6.setObjectName(_fromUtf8("label_6"))
        self.verticalLayout_3.addWidget(self.label_6)
        self.label_5 = QtGui.QLabel(self.gridLayoutWidget)
        self.label_5.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.label_5.setAlignment(QtCore.Qt.AlignCenter)
        self.label_5.setObjectName(_fromUtf8("label_5"))
        self.verticalLayout_3.addWidget(self.label_5)
        self.horizontalLayout = QtGui.QHBoxLayout()
        self.horizontalLayout.setSpacing(0)
        self.horizontalLayout.setSizeConstraint(QtGui.QLayout.SetDefaultConstraint)
        self.horizontalLayout.setObjectName(_fromUtf8("horizontalLayout"))
        self.btn_AIF1TX1_1 = QtGui.QPushButton(self.gridLayoutWidget)
        self.btn_AIF1TX1_1.setMouseTracking(False)
        self.btn_AIF1TX1_1.setFocusPolicy(QtCore.Qt.StrongFocus)
        self.btn_AIF1TX1_1.setAcceptDrops(True)
        self.btn_AIF1TX1_1.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.btn_AIF1TX1_1.setText(_fromUtf8(""))
        icon1 = QtGui.QIcon()
        icon1.addPixmap(QtGui.QPixmap(_fromUtf8(":/input_small.png")), QtGui.QIcon.Normal, QtGui.QIcon.Off)
        self.btn_AIF1TX1_1.setIcon(icon1)
        self.btn_AIF1TX1_1.setFlat(True)
        self.btn_AIF1TX1_1.setObjectName(_fromUtf8("btn_AIF1TX1_1"))
        self.horizontalLayout.addWidget(self.btn_AIF1TX1_1)
        self.btn_AIF1TX1_2 = QtGui.QPushButton(self.gridLayoutWidget)
        self.btn_AIF1TX1_2.setAcceptDrops(True)
        self.btn_AIF1TX1_2.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.btn_AIF1TX1_2.setText(_fromUtf8(""))
        self.btn_AIF1TX1_2.setIcon(icon1)
        self.btn_AIF1TX1_2.setFlat(True)
        self.btn_AIF1TX1_2.setObjectName(_fromUtf8("btn_AIF1TX1_2"))
        self.horizontalLayout.addWidget(self.btn_AIF1TX1_2)
        self.btn_AIF1TX1_3 = QtGui.QPushButton(self.gridLayoutWidget)
        self.btn_AIF1TX1_3.setAcceptDrops(True)
        self.btn_AIF1TX1_3.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.btn_AIF1TX1_3.setText(_fromUtf8(""))
        self.btn_AIF1TX1_3.setIcon(icon1)
        self.btn_AIF1TX1_3.setFlat(True)
        self.btn_AIF1TX1_3.setObjectName(_fromUtf8("btn_AIF1TX1_3"))
        self.horizontalLayout.addWidget(self.btn_AIF1TX1_3)
        self.btn_AIF1TX1_4 = QtGui.QPushButton(self.gridLayoutWidget)
        self.btn_AIF1TX1_4.setAcceptDrops(True)
        self.btn_AIF1TX1_4.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.btn_AIF1TX1_4.setText(_fromUtf8(""))
        self.btn_AIF1TX1_4.setIcon(icon1)
        self.btn_AIF1TX1_4.setFlat(True)
        self.btn_AIF1TX1_4.setObjectName(_fromUtf8("btn_AIF1TX1_4"))
        self.horizontalLayout.addWidget(self.btn_AIF1TX1_4)
        self.verticalLayout_3.addLayout(self.horizontalLayout)
        self.horizontalLayout_3.addLayout(self.verticalLayout_3)
        self.verticalLayout_4 = QtGui.QVBoxLayout()
        self.verticalLayout_4.setObjectName(_fromUtf8("verticalLayout_4"))
        self.label_7 = QtGui.QLabel(self.gridLayoutWidget)
        self.label_7.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.label_7.setAlignment(QtCore.Qt.AlignCenter)
        self.label_7.setObjectName(_fromUtf8("label_7"))
        self.verticalLayout_4.addWidget(self.label_7)
        self.label_8 = QtGui.QLabel(self.gridLayoutWidget)
        self.label_8.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.label_8.setAlignment(QtCore.Qt.AlignCenter)
        self.label_8.setObjectName(_fromUtf8("label_8"))
        self.verticalLayout_4.addWidget(self.label_8)
        self.horizontalLayout_2 = QtGui.QHBoxLayout()
        self.horizontalLayout_2.setSpacing(1)
        self.horizontalLayout_2.setSizeConstraint(QtGui.QLayout.SetDefaultConstraint)
        self.horizontalLayout_2.setObjectName(_fromUtf8("horizontalLayout_2"))
        self.btn_AIF1TX2_1 = QtGui.QPushButton(self.gridLayoutWidget)
        self.btn_AIF1TX2_1.setAcceptDrops(True)
        self.btn_AIF1TX2_1.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.btn_AIF1TX2_1.setText(_fromUtf8(""))
        self.btn_AIF1TX2_1.setIcon(icon1)
        self.btn_AIF1TX2_1.setFlat(True)
        self.btn_AIF1TX2_1.setObjectName(_fromUtf8("btn_AIF1TX2_1"))
        self.horizontalLayout_2.addWidget(self.btn_AIF1TX2_1)
        self.btn_AIF1TX2_2 = QtGui.QPushButton(self.gridLayoutWidget)
        self.btn_AIF1TX2_2.setAcceptDrops(True)
        self.btn_AIF1TX2_2.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.btn_AIF1TX2_2.setText(_fromUtf8(""))
        self.btn_AIF1TX2_2.setIcon(icon1)
        self.btn_AIF1TX2_2.setFlat(True)
        self.btn_AIF1TX2_2.setObjectName(_fromUtf8("btn_AIF1TX2_2"))
        self.horizontalLayout_2.addWidget(self.btn_AIF1TX2_2)
        self.btn_AIF1TX2_3 = QtGui.QPushButton(self.gridLayoutWidget)
        sizePolicy = QtGui.QSizePolicy(QtGui.QSizePolicy.Minimum, QtGui.QSizePolicy.Minimum)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.btn_AIF1TX2_3.sizePolicy().hasHeightForWidth())
        self.btn_AIF1TX2_3.setSizePolicy(sizePolicy)
        self.btn_AIF1TX2_3.setAcceptDrops(True)
        self.btn_AIF1TX2_3.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.btn_AIF1TX2_3.setText(_fromUtf8(""))
        self.btn_AIF1TX2_3.setIcon(icon1)
        self.btn_AIF1TX2_3.setFlat(True)
        self.btn_AIF1TX2_3.setObjectName(_fromUtf8("btn_AIF1TX2_3"))
        self.horizontalLayout_2.addWidget(self.btn_AIF1TX2_3)
        self.btn_AIF1TX2_4 = QtGui.QPushButton(self.gridLayoutWidget)
        self.btn_AIF1TX2_4.setAcceptDrops(True)
        self.btn_AIF1TX2_4.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.btn_AIF1TX2_4.setText(_fromUtf8(""))
        self.btn_AIF1TX2_4.setIcon(icon1)
        self.btn_AIF1TX2_4.setFlat(True)
        self.btn_AIF1TX2_4.setObjectName(_fromUtf8("btn_AIF1TX2_4"))
        self.horizontalLayout_2.addWidget(self.btn_AIF1TX2_4)
        self.verticalLayout_4.addLayout(self.horizontalLayout_2)
        self.horizontalLayout_3.addLayout(self.verticalLayout_4)
        self.gridLayout.addLayout(self.horizontalLayout_3, 1, 1, 1, 1)
        self.lbl_playback = QtGui.QLabel(self.gridLayoutWidget)
        self.lbl_playback.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.lbl_playback.setTextFormat(QtCore.Qt.AutoText)
        self.lbl_playback.setObjectName(_fromUtf8("lbl_playback"))
        self.gridLayout.addWidget(self.lbl_playback, 0, 0, 1, 1)
        self.label_9 = QtGui.QLabel(self.gridLayoutWidget)
        self.label_9.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.label_9.setAlignment(QtCore.Qt.AlignCenter)
        self.label_9.setObjectName(_fromUtf8("label_9"))
        self.gridLayout.addWidget(self.label_9, 0, 1, 1, 1)
        self.dial = QtGui.QDial(self.centralwidget)
        self.dial.setGeometry(QtCore.QRect(30, 360, 50, 64))
        self.dial.setObjectName(_fromUtf8("dial"))
        self.label_10 = QtGui.QLabel(self.centralwidget)
        self.label_10.setGeometry(QtCore.QRect(20, 320, 52, 15))
        self.label_10.setObjectName(_fromUtf8("label_10"))
        self.widget = QtGui.QWidget(self.centralwidget)
        self.widget.setGeometry(QtCore.QRect(160, 400, 331, 21))
        self.widget.setObjectName(_fromUtf8("widget"))
        self.groupBox = QtGui.QGroupBox(self.centralwidget)
        self.groupBox.setGeometry(QtCore.QRect(130, 130, 361, 271))
        self.groupBox.setObjectName(_fromUtf8("groupBox"))
        self.graphicsView = WiringGraphicsView(self.groupBox)
        self.graphicsView.setGeometry(QtCore.QRect(40, 30, 291, 241))
        self.graphicsView.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOff)
        self.graphicsView.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOff)
        brush = QtGui.QBrush(QtGui.QColor(0, 0, 0))
        brush.setStyle(QtCore.Qt.NoBrush)
        self.graphicsView.setBackgroundBrush(brush)
        self.graphicsView.setObjectName(_fromUtf8("graphicsView"))
        self.btn_AIF1RX1_2 = DragButton(self.groupBox)
        self.btn_AIF1RX1_2.setGeometry(QtCore.QRect(50, 50, 51, 31))
        self.btn_AIF1RX1_2.setBaseSize(QtCore.QSize(0, 0))
        self.btn_AIF1RX1_2.setMouseTracking(True)
        self.btn_AIF1RX1_2.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.btn_AIF1RX1_2.setText(_fromUtf8(""))
        self.btn_AIF1RX1_2.setIcon(icon)
        self.btn_AIF1RX1_2.setAutoDefault(False)
        self.btn_AIF1RX1_2.setDefault(False)
        self.btn_AIF1RX1_2.setFlat(True)
        self.btn_AIF1RX1_2.setObjectName(_fromUtf8("btn_AIF1RX1_2"))
        self.btn_AIF1TX1_5 = DragButton(self.groupBox)
        self.btn_AIF1TX1_5.setGeometry(QtCore.QRect(270, 150, 41, 31))
        self.btn_AIF1TX1_5.setMouseTracking(False)
        self.btn_AIF1TX1_5.setFocusPolicy(QtCore.Qt.StrongFocus)
        self.btn_AIF1TX1_5.setAcceptDrops(True)
        self.btn_AIF1TX1_5.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.btn_AIF1TX1_5.setText(_fromUtf8(""))
        self.btn_AIF1TX1_5.setIcon(icon1)
        self.btn_AIF1TX1_5.setFlat(True)
        self.btn_AIF1TX1_5.setObjectName(_fromUtf8("btn_AIF1TX1_5"))
        self.btn_AIF1RX1_3 = DragButton(self.groupBox)
        self.btn_AIF1RX1_3.setGeometry(QtCore.QRect(60, 110, 51, 27))
        self.btn_AIF1RX1_3.setBaseSize(QtCore.QSize(0, 0))
        self.btn_AIF1RX1_3.setMouseTracking(True)
        self.btn_AIF1RX1_3.setAcceptDrops(False)
        self.btn_AIF1RX1_3.setLocale(QtCore.QLocale(QtCore.QLocale.English, QtCore.QLocale.UnitedStates))
        self.btn_AIF1RX1_3.setText(_fromUtf8(""))
        self.btn_AIF1RX1_3.setIcon(icon)
        self.btn_AIF1RX1_3.setAutoDefault(False)
        self.btn_AIF1RX1_3.setDefault(False)
        self.btn_AIF1RX1_3.setFlat(True)
        self.btn_AIF1RX1_3.setObjectName(_fromUtf8("btn_AIF1RX1_3"))
        WolfsonMixerWindow.setCentralWidget(self.centralwidget)
        self.menubar = QtGui.QMenuBar(WolfsonMixerWindow)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 562, 23))
        self.menubar.setObjectName(_fromUtf8("menubar"))
        WolfsonMixerWindow.setMenuBar(self.menubar)
        self.statusbar = QtGui.QStatusBar(WolfsonMixerWindow)
        self.statusbar.setObjectName(_fromUtf8("statusbar"))
        WolfsonMixerWindow.setStatusBar(self.statusbar)

        self.retranslateUi(WolfsonMixerWindow)
        QtCore.QObject.connect(self.dial, QtCore.SIGNAL(_fromUtf8("valueChanged(int)")), self.label_10.setNum)
        QtCore.QMetaObject.connectSlotsByName(WolfsonMixerWindow)

    def retranslateUi(self, WolfsonMixerWindow):
        WolfsonMixerWindow.setWindowTitle(_translate("WolfsonMixerWindow", "Wolfson Mixer", None))
        self.label_2.setText(_translate("WolfsonMixerWindow", "AIF1RX1", None))
        self.label.setText(_translate("WolfsonMixerWindow", "L", None))
        self.label_3.setText(_translate("WolfsonMixerWindow", "AIF1RX2", None))
        self.label_4.setText(_translate("WolfsonMixerWindow", "R", None))
        self.label_6.setText(_translate("WolfsonMixerWindow", "AIF1TX1", None))
        self.label_5.setText(_translate("WolfsonMixerWindow", "L", None))
        self.label_7.setText(_translate("WolfsonMixerWindow", "AIF1TX2", None))
        self.label_8.setText(_translate("WolfsonMixerWindow", "R", None))
        self.lbl_playback.setText(_translate("WolfsonMixerWindow", "<html><head/><body><p><span style=\" font-weight:600;\">Playback (from RPi)</span></p></body></html>", None))
        self.label_9.setText(_translate("WolfsonMixerWindow", "<html><head/><body><p><span style=\" font-weight:600;\">Record (to RPi)</span></p></body></html>", None))
        self.label_10.setText(_translate("WolfsonMixerWindow", "TextLabel", None))
        self.groupBox.setTitle(_translate("WolfsonMixerWindow", "GroupBox", None))

from wiringgraphicsview import WiringGraphicsView
from dragbutton import DragButton
import icons_rc

Answer 1

以下是如何在QWidgets中的两个QGraphicsScene之间绘制一条线的示例。原则上它很简单。窗口小部件的矩形可以由QGraphicsProxyWidget.geometry()访问，并且位于场景坐标中。因此，人们可以根据这一点绘制一条线。

示例：

from PySide import QtGui, QtCore

app = QtGui.QApplication([])

scene = QtGui.QGraphicsScene()

# put a button into the scene and move it
button1 = QtGui.QPushButton('Button 1')
scene_button1 = scene.addWidget(button1)
r1 = scene_button1.geometry()
r1.moveTo(-100, -50)
scene_button1.setGeometry(r1)

# put another button into the scene
button2 = QtGui.QPushButton('Button 2')
scene_button2 = scene.addWidget(button2)
r2 = scene_button2.geometry()

# add a line between the centers of each rectangles
scene.addLine(r1.x() + r1.width() / 2, r1.y() + r1.height() / 2, r2.x() + r2.width() / 2, r2.y() + r2.height() / 2)

# view on the scene
view = QtGui.QGraphicsView(scene)
view.resize(300, 200)
view.show()

app.exec_()

它看起来像：

enter image description here

现在整个拖着因为它不是那么微不足道。不是QGraphicsProxyWidget而是原始QWidget，似乎是获取鼠标移动/按下事件。我们只是发出一个新信号（拖动）并将其连接到一个可以移动场景中的按钮的函数（使用scene.addWidget的返回，QGraphicsProxyWidget也是QGraphicsItem ）。它还重绘两个按钮之间的线，以便它们保持连接。

from PySide import QtGui, QtCore

class DraggablePushButton(QtGui.QPushButton):
    """
        Extension of QPushButton that emits a dragged signal (QPointF which is the delta in movement of the mouse) as
        long as it is pressed.
    """

    dragged = QtCore.Signal(QtCore.QPointF)

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

    def mousePressEvent(self, event):
        self.position = event.globalPos()

    def mouseMoveEvent(self, event):
        # will only by called if the mouse is also pressed
        position_now = event.globalPos()
        self.dragged.emit(position_now - self.position)
        self.position = position_now

def move_scene_button1_and_redraw_line(drag):
    # move the button1 by a certain delta position and change line connecting them with it
    scene_button1.moveBy(drag.x(), drag.y())
    r1 = scene_button1.geometry()
    line_item.setLine(r1.x() + r1.width() / 2, r1.y() + r1.height() / 2, r2.x() + r2.width() / 2, r2.y() + r2.height() / 2)

app = QtGui.QApplication([])

# the graphicsscene
scene = QtGui.QGraphicsScene()
scene.setSceneRect(-150, -100, 300, 200)

# put a draggable button into the scene
button1 = DraggablePushButton('Button 1')
scene_button1 = scene.addWidget(button1)
scene_button1.setPos(-100, -50)
r1 = scene_button1.geometry()

# connect dragged events to move of scene button
button1.dragged.connect(move_scene_button1_and_redraw_line)

# put another still standing button into the scene
button2 = QtGui.QPushButton('Button 2')
scene_button2 = scene.addWidget(button2)
r2 = scene_button2.geometry()

# draw line between button1 and button2
line_item = scene.addLine(r1.x() + r1.width() / 2, r1.y() + r1.height() / 2, r2.x() + r2.width() / 2, r2.y() + r2.height() / 2)

# view on the scene
view = QtGui.QGraphicsView(scene)
view.resize(330, 220)
view.show()

app.exec_()

它仍然看起来像：

enter image description here

在图形视图上的错误位置绘制的小部件之间的线

1 个答案: