如何旋转QPushButton？

Question

我想用Python和Qt4来旋转一个QPushButton（或者至少是它的文字），让它可以竖着放。我在网上看到过一些相关的文档，但我看得一头雾水——因为那些是C语言的，我对C语言不太懂。

根据我所读到的内容，似乎需要重新实现paintEvent()这个处理函数，创建一个QPainter对象并进行旋转。不过，我搞不清楚的是，怎么只针对我需要的那个QString或QPushButton来做这件事。我原以为QPaintEvent会有一个“发送者”属性，就像信号那样，但实际上没有。我从这个事件中只能得到一个QRect或QRegion。

我该如何找到与我的按钮或它的标签相关的事件呢？
或者说，真正的问题是，怎么旋转一个QPushButton？

Mru在下面建议了一些C++的例子，这个例子是完全重新实现了QPushButton。由于我对C++一窍不通，而且我并不需要完整的重新实现，我尝试根据那个例子在Python中重新实现painEvent()处理函数。

这是我翻译的内容，但它并不工作 :\

#!/usr/bin/env python


from PyQt4 import QtGui, QtCore
import sys



class RotatedButton(QtGui.QPushButton):
    def __init__(self, text, parent, orientation = "west"):
        QtGui.QPushButton.__init__(self, text, parent)
        self.orientation = orientation

    def paintEvent(self, event):
        painter = QtGui.QStylePainter(self)
        if self.orientation == 'west':
            painter.rotate(90)
        elif self.orientation == 'east':
            painter.rotate(270)
        else:
            raise TypeError
        painter.drawControl(QtGui.QStyle.CE_PushButton, self.getSyleOptions())


    def getSyleOptions(self):

        options = QtGui.QStyleOptionButton()
        options.initFrom(self)        
        size = options.rect.size()
        size.transpose()
        options.rect.setSize(size)
        options.features = QtGui.QStyleOptionButton.None
        options.text = self.text()
        options.icon = self.icon()
        options.iconSize = self.iconSize()
        return options


class Main(QtGui.QFrame):
    def __init__(self):
        QtGui.QFrame.__init__(self)

        self.count = 0
        self.application = QtCore.QCoreApplication.instance()
        self.layout = QtGui.QHBoxLayout()
        self.button = RotatedButton("Hello", self, orientation="west")
        self.layout.addWidget(self.button)
        self.setLayout(self.layout)



if __name__ == '__main__':

    application = QtGui.QApplication(sys.argv)    
    application.main = Main()
    application.main.show()
    sys.exit(application.exec_())

Answer 1

我知道这条信息比原帖晚了几年，但如果你只是想让文字竖着显示而不是横着，这个方法是有效的。你可以使用QTextDocument和一些HTML代码。在每个字母后面加上

<br>

。

QTextDocument doc;
doc.setHtml("<p align=center><font>B<br>u<br>t<br>t<br>o<br>n</font></p>");
doc.setTextWidth(doc.size().width());

QPixmap pixmap(doc.size().width(), doc.size().height());
pixmap.fill( Qt::transparent );
QPainter painter(&pixmap);
doc.drawContents(&painter);

QPushButton button;
button->setIconSize(pixmap.size());
button->setIcon(pixmap);

Answer 2

如果你想让这段代码同时适用于“东”和“西”这两个方向的参数，你应该使用下面的代码：

#!/usr/bin/env python

from PyQt4 import QtGui, QtCore
import sys

class RotatedButton(QtGui.QPushButton):
    def __init__(self, text, parent, orientation = "west"):
        super(RotatedButton,self).__init__(text, parent)
        self.orientation = orientation

    def paintEvent(self, event):
        painter = QtGui.QStylePainter(self)
        if self.orientation == "east":
            painter.rotate(270)
            painter.translate(-1 * self.height(), 0);
        if self.orientation == "west":
            painter.rotate(90)
            painter.translate(0, -1 * self.width());
        painter.drawControl(QtGui.QStyle.CE_PushButton, self.getSyleOptions())

    def minimumSizeHint(self):
        size = super(RotatedButton, self).minimumSizeHint()
        size.transpose()
        return size

    def sizeHint(self):
        size = super(RotatedButton, self).sizeHint()
        size.transpose()
        return size

    def getSyleOptions(self):
        options = QtGui.QStyleOptionButton()
        options.initFrom(self)
        size = options.rect.size()
        size.transpose()
        options.rect.setSize(size)
        options.features = QtGui.QStyleOptionButton.None
        if self.isFlat():
            options.features |= QtGui.QStyleOptionButton.Flat
        if self.menu():
            options.features |= QtGui.QStyleOptionButton.HasMenu
        if self.autoDefault() or self.isDefault():
            options.features |= QtGui.QStyleOptionButton.AutoDefaultButton
        if self.isDefault():
            options.features |= QtGui.QStyleOptionButton.DefaultButton
        if self.isDown() or (self.menu() and self.menu().isVisible()):
            options.state |= QtGui.QStyle.State_Sunken
        if self.isChecked():
            options.state |= QtGui.QStyle.State_On
        if not self.isFlat() and not self.isDown():
            options.state |= QtGui.QStyle.State_Raised

        options.text = self.text()
        options.icon = self.icon()
        options.iconSize = self.iconSize()
        return options


class Main(QtGui.QFrame):
    def __init__(self):
        QtGui.QFrame.__init__(self)

        self.application = QtCore.QCoreApplication.instance()
        self.layout = QtGui.QHBoxLayout()
        self.button = RotatedButton("Hello", self, orientation="west")
        self.layout.addWidget(self.button)
        self.setLayout(self.layout)

if __name__ == '__main__':

    application = QtGui.QApplication(sys.argv)
    application.main = Main()
    application.main.show()
    sys.exit(application.exec_())

Answer 3

根据你的代码：

#!/usr/bin/env python

from PyQt4 import QtGui, QtCore
import sys

class RotatedButton(QtGui.QPushButton):
    def __init__(self, text, parent, orientation = "west"):
        super(RotatedButton,self).__init__(text, parent)
        self.orientation = orientation

    def paintEvent(self, event):
        painter = QtGui.QStylePainter(self)
        painter.rotate(90)
        painter.translate(0, -1 * self.width());
        painter.drawControl(QtGui.QStyle.CE_PushButton, self.getSyleOptions())

    def minimumSizeHint(self):
        size = super(RotatedButton, self).minimumSizeHint()
        size.transpose()
        return size

    def sizeHint(self):
        size = super(RotatedButton, self).sizeHint()
        size.transpose()
        return size

    def getSyleOptions(self):
        options = QtGui.QStyleOptionButton()
        options.initFrom(self)
        size = options.rect.size()
        size.transpose()
        options.rect.setSize(size)
        options.features = QtGui.QStyleOptionButton.None
        if self.isFlat():
            options.features |= QtGui.QStyleOptionButton.Flat
        if self.menu():
            options.features |= QtGui.QStyleOptionButton.HasMenu
        if self.autoDefault() or self.isDefault():
            options.features |= QtGui.QStyleOptionButton.AutoDefaultButton
        if self.isDefault():
            options.features |= QtGui.QStyleOptionButton.DefaultButton
        if self.isDown() or (self.menu() and self.menu().isVisible()):
            options.state |= QtGui.QStyle.State_Sunken
        if self.isChecked():
            options.state |= QtGui.QStyle.State_On
        if not self.isFlat() and not self.isDown():
            options.state |= QtGui.QStyle.State_Raised

        options.text = self.text()
        options.icon = self.icon()
        options.iconSize = self.iconSize()
        return options


class Main(QtGui.QFrame):
    def __init__(self):
        QtGui.QFrame.__init__(self)

        self.application = QtCore.QCoreApplication.instance()
        self.layout = QtGui.QHBoxLayout()
        self.button = RotatedButton("Hello", self, orientation="west")
        self.layout.addWidget(self.button)
        self.setLayout(self.layout)

if __name__ == '__main__':

    application = QtGui.QApplication(sys.argv)
    application.main = Main()
    application.main.show()
    sys.exit(application.exec_())