python - PyQt5根据输入值自动绘制

我最近用Qpaint创建了一个小部件，希望将值传递给它，同时强制Qpaint小部件从输入值中绘制。这个想法是从Qdialog定义一个数据值并将其传递给主窗口小部件，然后将该值传递给Qpaint Widget class。我希望当用户单击“获取值”按钮时，将出现一个对话框小部件并插入一些int值，然后将其传递给主小部件。从那里传递值以更正class Paint。这将绘制并显示结果。我尝试使用Qlabel，首先将值分配给Qlabel or QlineEdit，

class Button(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(Button, self).__init__(parent)
          ---------

        self.value = QtWidgets.QLabel()

           --------

然后在paint class中调用这些值或文本。然后将其分配给Qpaint event。但似乎不起作用。

class Paint(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(Paint, self).__init__(parent)

        self.button = Button()
        self.Value = self.button.value

          ---------

        painter.drawRect(100,100,250,250)     <----- instead of value 250 having self.Value

代码Main.py

import sys
from PyQt5 import QtCore, QtGui, QtWidgets
from datainput import *


class Foo(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(Foo, self).__init__(parent)
        self.setGeometry(QtCore.QRect(200, 100, 800, 800))

        self.button = Button()
        self.paint = Paint()

        self.lay = QtWidgets.QVBoxLayout()
        self.lay.addWidget(self.paint)
        self.lay.addWidget(self.button)
        self.setLayout(self.lay)

class Paint(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(Paint, self).__init__(parent)

        self.button = Button()
        self.Value = self.button.value

        self.setBackgroundRole(QtGui.QPalette.Base)
        self.setAutoFillBackground(True)

    def paintEvent(self, event):

        self.pen = QtGui.QPen()
        self.brush = QtGui.QBrush( QtCore.Qt.gray, QtCore.Qt.Dense7Pattern)
        painter = QtGui.QPainter(self)
        painter.setRenderHint(QtGui.QPainter.Antialiasing)
        painter.setPen(self.pen)
        painter.setBrush(self.brush)
        painter.drawRect(100,100,250,250)
        painter.setBrush(QtGui.QBrush())

class Button(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(Button, self).__init__(parent)

        getbutton = QtWidgets.QPushButton('Getting values')
        Alay = QtWidgets.QVBoxLayout(self)
        Alay.addWidget(getbutton)

        self.value = QtWidgets.QLabel()

        getbutton.clicked.connect(self.getbuttonfunc)


    def getbuttonfunc(self):
        subwindow=Dinput()
        subwindow.setWindowModality(QtCore.Qt.ApplicationModal)
        if subwindow.exec_() == QtWidgets.QDialog.Accepted:
            self._output = subwindow.valueEdit.text()
            return self.value.setText(self._output)


if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    w = Foo()
    w.show()
    sys.exit(app.exec_())

输入Q对话代码datainput.py

import sys
from PyQt5 import QtCore, QtGui, QtWidgets

class Dinput(QtWidgets.QDialog):
    def __init__(self, parent=None):
        super(Dinput, self).__init__(parent)

        valuelabel = QtWidgets.QLabel('Input: ')
        self.valueEdit = QtWidgets.QLineEdit()

        buttonBox = QtWidgets.QDialogButtonBox()
        buttonBox.setStandardButtons(QtWidgets.QDialogButtonBox.Cancel|QtWidgets.QDialogButtonBox.Ok)
        buttonBox.accepted.connect(self.accept)
        buttonBox.rejected.connect(self.close)

        self.Alay = QtWidgets.QHBoxLayout()
        self.Alay.addWidget(valuelabel)
        self.Alay.addWidget(self.valueEdit)

        self.Blay = QtWidgets.QVBoxLayout()
        self.Blay.addLayout(self.Alay)
        self.Blay.addWidget(buttonBox)
        self.setLayout(self.Blay)

    def closeEvent(self, event):
        super(Dinput, self).closeEvent(event)

    def accept(self):
        super(Dinput, self).accept()

if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    w = Dinput()
    w.show()
    sys.exit(app.exec_())

可视化



感谢您的帮助。谢谢

最佳答案

datainput是无关紧要的，您的任务只是获取一个数字，因此对于空间问题，我将不使用它，而将使用QInputDialog::getInt()。问题出了，在任何时候都可以获取值的情况下，策略是通过信号将更改通知另一个视图，在接收值的插槽中是更新存储值的变量并调用更新，以便在需要时调用paintEvent，并在paintEvent中使用存储值的变量。

import sys
from PyQt5 import QtCore, QtGui, QtWidgets


class Foo(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(Foo, self).__init__(parent)
        self.setGeometry(QtCore.QRect(200, 100, 800, 800))

        self.button = Button()
        self.paint = Paint()
        self.button.valueChanged.connect(self.paint.set_size_square)

        self.lay = QtWidgets.QVBoxLayout(self)
        self.lay.addWidget(self.paint)
        self.lay.addWidget(self.button)

class Paint(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(Paint, self).__init__(parent)
        self.setBackgroundRole(QtGui.QPalette.Base)
        self.setAutoFillBackground(True)
        self._size_square = 250

    @QtCore.pyqtSlot(int)
    def set_size_square(self, v):
        self._size_square = v
        self.update()

    def paintEvent(self, event):
        pen = QtGui.QPen()
        brush = QtGui.QBrush( QtCore.Qt.gray, QtCore.Qt.Dense7Pattern)
        painter = QtGui.QPainter(self)
        painter.setRenderHint(QtGui.QPainter.Antialiasing)
        painter.setPen(pen)
        painter.setBrush(brush)
        r = QtCore.QRect(QtCore.QPoint(100, 100), self._size_square*QtCore.QSize(1, 1))
        painter.drawRect(r)

class Button(QtWidgets.QWidget):
    valueChanged = QtCore.pyqtSignal(int)

    def __init__(self, parent=None):
        super(Button, self).__init__(parent)
        getbutton = QtWidgets.QPushButton('Getting values')
        Alay = QtWidgets.QVBoxLayout(self)
        Alay.addWidget(getbutton)
        self.value = QtWidgets.QLabel()
        getbutton.clicked.connect(self.getbuttonfunc)

    @QtCore.pyqtSlot()
    def getbuttonfunc(self):
        number, ok = QtWidgets.QInputDialog.getInt(self, self.tr("Set Number"),
                                         self.tr("Input:"), 1, 1)
        if ok:
            self.valueChanged.emit(number)

if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    w = Foo()
    w.show()
    sys.exit(app.exec_())