Change background color of QTabWidget tabs

Question

Is it possible in PYQT4 to change the background color of tabs for a QTabWidget? There is a way to change the color of the text but not the background color of the tab.

I have a program with multiple tabs, and I want to give each level its own background color. See attached example.

from PyQt4 import QtCore, QtGui

try:
    _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
    _fromUtf8 = lambda s: s

class Ui_Dialog(object):
    def setupUi(self, Dialog):
        Dialog.setObjectName(_fromUtf8("Dialog"))
        Dialog.resize(661, 397)
        self.verticalLayout = QtGui.QVBoxLayout(Dialog)
        self.verticalLayout.setObjectName(_fromUtf8("verticalLayout"))
        self.tabWidget = QtGui.QTabWidget(Dialog)
        self.tabWidget.setObjectName(_fromUtf8("tabWidget"))
        self.tab = QtGui.QWidget()
        self.tab.setObjectName(_fromUtf8("tab"))
        self.verticalLayout_2 = QtGui.QVBoxLayout(self.tab)
        self.verticalLayout_2.setObjectName(_fromUtf8("verticalLayout_2"))
        self.tabWidget_2 = QtGui.QTabWidget(self.tab)
        self.tabWidget_2.setObjectName(_fromUtf8("tabWidget_2"))
        self.tab_3 = QtGui.QWidget()
        self.tab_3.setObjectName(_fromUtf8("tab_3"))
        self.verticalLayout_3 = QtGui.QVBoxLayout(self.tab_3)
        self.verticalLayout_3.setObjectName(_fromUtf8("verticalLayout_3"))
        self.tabWidget_3 = QtGui.QTabWidget(self.tab_3)
        self.tabWidget_3.setObjectName(_fromUtf8("tabWidget_3"))
        self.tab_5 = QtGui.QWidget()
        self.tab_5.setObjectName(_fromUtf8("tab_5"))
        self.verticalLayout_4 = QtGui.QVBoxLayout(self.tab_5)
        self.verticalLayout_4.setObjectName(_fromUtf8("verticalLayout_4"))
        self.tabWidget_4 = QtGui.QTabWidget(self.tab_5)
        self.tabWidget_4.setObjectName(_fromUtf8("tabWidget_4"))
        self.tab_7 = QtGui.QWidget()
        self.tab_7.setObjectName(_fromUtf8("tab_7"))
        self.verticalLayout_5 = QtGui.QVBoxLayout(self.tab_7)
        self.verticalLayout_5.setObjectName(_fromUtf8("verticalLayout_5"))
        self.tabWidget_5 = QtGui.QTabWidget(self.tab_7)
        self.tabWidget_5.setElideMode(QtCore.Qt.ElideRight)
        self.tabWidget_5.setObjectName(_fromUtf8("tabWidget_5"))
        self.tab_9 = QtGui.QWidget()
        self.tab_9.setObjectName(_fromUtf8("tab_9"))
        self.tabWidget_5.addTab(self.tab_9, _fromUtf8(""))
        self.tab_10 = QtGui.QWidget()
        self.tab_10.setObjectName(_fromUtf8("tab_10"))
        self.tabWidget_5.addTab(self.tab_10, _fromUtf8(""))
        self.verticalLayout_5.addWidget(self.tabWidget_5)
        self.tabWidget_4.addTab(self.tab_7, _fromUtf8(""))
        self.tab_8 = QtGui.QWidget()
        self.tab_8.setObjectName(_fromUtf8("tab_8"))
        self.tabWidget_4.addTab(self.tab_8, _fromUtf8(""))
        self.verticalLayout_4.addWidget(self.tabWidget_4)
        self.tabWidget_3.addTab(self.tab_5, _fromUtf8(""))
        self.tab_6 = QtGui.QWidget()
        self.tab_6.setObjectName(_fromUtf8("tab_6"))
        self.tabWidget_3.addTab(self.tab_6, _fromUtf8(""))
        self.verticalLayout_3.addWidget(self.tabWidget_3)
        self.tabWidget_2.addTab(self.tab_3, _fromUtf8(""))
        self.tab_4 = QtGui.QWidget()
        self.tab_4.setObjectName(_fromUtf8("tab_4"))
        self.tabWidget_2.addTab(self.tab_4, _fromUtf8(""))
        self.verticalLayout_2.addWidget(self.tabWidget_2)
        self.tabWidget.addTab(self.tab, _fromUtf8(""))
        self.tab_2 = QtGui.QWidget()
        self.tab_2.setObjectName(_fromUtf8("tab_2"))
        self.tabWidget.addTab(self.tab_2, _fromUtf8(""))
        self.verticalLayout.addWidget(self.tabWidget)
        self.buttonBox = QtGui.QDialogButtonBox(Dialog)
        self.buttonBox.setOrientation(QtCore.Qt.Horizontal)
        self.buttonBox.setStandardButtons(QtGui.QDialogButtonBox.Cancel|QtGui.QDialogButtonBox.Ok)
        self.buttonBox.setObjectName(_fromUtf8("buttonBox"))
        self.verticalLayout.addWidget(self.buttonBox)

        self.retranslateUi(Dialog)
        self.tabWidget.setCurrentIndex(0)
        self.tabWidget_2.setCurrentIndex(0)
        self.tabWidget_3.setCurrentIndex(0)
        self.tabWidget_4.setCurrentIndex(0)
        self.tabWidget_5.setCurrentIndex(0)
        QtCore.QObject.connect(self.buttonBox, QtCore.SIGNAL(_fromUtf8("accepted()")), Dialog.accept)
        QtCore.QObject.connect(self.buttonBox, QtCore.SIGNAL(_fromUtf8("rejected()")), Dialog.reject)
        QtCore.QMetaObject.connectSlotsByName(Dialog)

    def retranslateUi(self, Dialog):
        Dialog.setWindowTitle(QtGui.QApplication.translate("Dialog", "Dialog", None, QtGui.QApplication.UnicodeUTF8))
        self.tabWidget_5.setTabText(self.tabWidget_5.indexOf(self.tab_9), QtGui.QApplication.translate("Dialog", "Tab 9", None, QtGui.QApplication.UnicodeUTF8))
        self.tabWidget_5.setTabText(self.tabWidget_5.indexOf(self.tab_10), QtGui.QApplication.translate("Dialog", "Tab 10", None, QtGui.QApplication.UnicodeUTF8))
        self.tabWidget_4.setTabText(self.tabWidget_4.indexOf(self.tab_7), QtGui.QApplication.translate("Dialog", "Tab 7", None, QtGui.QApplication.UnicodeUTF8))
        self.tabWidget_4.setTabText(self.tabWidget_4.indexOf(self.tab_8), QtGui.QApplication.translate("Dialog", "Tab 8", None, QtGui.QApplication.UnicodeUTF8))
        self.tabWidget_3.setTabText(self.tabWidget_3.indexOf(self.tab_5), QtGui.QApplication.translate("Dialog", "Tab 5", None, QtGui.QApplication.UnicodeUTF8))
        self.tabWidget_3.setTabText(self.tabWidget_3.indexOf(self.tab_6), QtGui.QApplication.translate("Dialog", "Tab 6", None, QtGui.QApplication.UnicodeUTF8))
        self.tabWidget_2.setTabText(self.tabWidget_2.indexOf(self.tab_3), QtGui.QApplication.translate("Dialog", "Tab 3", None, QtGui.QApplication.UnicodeUTF8))
        self.tabWidget_2.setTabText(self.tabWidget_2.indexOf(self.tab_4), QtGui.QApplication.translate("Dialog", "Tab 4", None, QtGui.QApplication.UnicodeUTF8))
        self.tabWidget.setTabText(self.tabWidget.indexOf(self.tab), QtGui.QApplication.translate("Dialog", "Tab 1", None, QtGui.QApplication.UnicodeUTF8))
        self.tabWidget.setTabText(self.tabWidget.indexOf(self.tab_2), QtGui.QApplication.translate("Dialog", "Tab 2", None, QtGui.QApplication.UnicodeUTF8))
#
#------------------------------------------------------------------------------ 
#
#  For Testing
#
        self.tab_33 = QtGui.QWidget()
        self.tabWidget.addTab(self.tab_33, "Hell")
        QColor = QtGui.QColor(255, 85, 0)
        a = self.tabWidget.tabBar()
        a.setTabTextColor(0, QColor)


if __name__ == "__main__":
    import sys
    app = QtGui.QApplication(sys.argv)
    Dialog = QtGui.QDialog()
    ui = Ui_Dialog()
    ui.setupUi(Dialog)
    Dialog.show()
    sys.exit(app.exec_())

Answer 1

If you're using a widget-style which doesn't draw the tabs using pixmaps (see this Qt FAQ for details), you can create a subclass of QTabBar and re-colour the tabs in a reimplemented paintEvent, and then use QTabWidget.setTabBar to replace the default tab-bar. This allows the tabs to be coloured individually, which isn't possible using stylesheets.

Here's a simple demo:

PyQt5:

from PyQt5 import QtGui, QtWidgets

class TabBar(QtWidgets.QTabBar):
    def paintEvent(self, event):
        style = self.style()
        painter = QtGui.QPainter(self)
        option = QtWidgets.QStyleOptionTab()
        for index in range(self.count()):
            self.initStyleOption(option, index)
            bgcolor = QtGui.QColor(self.tabText(index))
            option.palette.setColor(QtGui.QPalette.Window, bgcolor)
            option.palette.setColor(QtGui.QPalette.Button, bgcolor)
            style.drawControl(QtWidgets.QStyle.CE_TabBarTab, option, painter)

class Window(QtWidgets.QTabWidget):
    def __init__(self):
        super().__init__()
        self.setTabBar(TabBar(self))
        for color in 'tomato orange yellow lightgreen skyblue plum'.split():
            self.addTab(QtWidgets.QWidget(self), color)

if __name__ == '__main__':

    app = QtWidgets.QApplication(['Test'])
    window = Window()
    window.setGeometry(600, 100, 420, 200)
    window.show()
    app.exec()

PyQt4:

from PyQt4 import QtGui

class TabBar(QtGui.QTabBar):
    def paintEvent(self, event):
        painter = QtGui.QStylePainter(self)
        option = QtGui.QStyleOptionTab()
        for index in range(self.count()):
            self.initStyleOption(option, index)
            bgcolor = QtGui.QColor(self.tabText(index))
            option.palette.setColor(QtGui.QPalette.Window, bgcolor)
            option.palette.setColor(QtGui.QPalette.Button, bgcolor)
            painter.drawControl(QtGui.QStyle.CE_TabBarTab, option)

class Window(QtGui.QTabWidget):
    def __init__(self):
        QtGui.QTabWidget.__init__(self)
        self.setTabBar(TabBar(self))
        for color in 'tomato orange yellow lightgreen skyblue plum'.split():
            self.addTab(QtGui.QWidget(self), color)

if __name__ == '__main__':

    import sys
    app = QtGui.QApplication(sys.argv)
    window = Window()
    window.resize(420, 200)
    window.show()
    sys.exit(app.exec_())

Answer 2

You may use qt style sheets to customize look of QTabWidget:

http://doc.qt.digia.com/4.7-snapshot/stylesheet-examples.html#customizing-qtabwidget-and-qtabbar

e.g.:

self.tabwidget.setStyleSheet('QTabBar::tab {background-color: red;}')