使Qt应用程序使用不同的系统字体大小

Question

I am working on a Qt application targeting Windows and Mac OS X. I have lots of dialogs with text in my application. I created the application on Windows, where I sized the dialogs to fit all of my text neatly. As soon as I compiled on Mac OS X, I realised all of the text doesn't fit properly. Furthermore, setting a different system font size in the Windows Control Panel causes all of dialog sizes to be incorrect.

How are you supposed to handle different system font sizes in Qt?

Answer 1

You don't: you let Qt do the job for you. Use layouts to arrange your widgets; avoid setting fixed sizes. Last point: I recommend to use Qt-Designer to create your interfaces.

Edit for Dmitry: here are Python files from 2 ui files (generated with pyuic4) each one with 2 QLabel. 1 Qlabel font is huge (72), the other is the default one (10).

1. Min and Max size are constrained: here if max font size is 10, the label is correctly displayed.

    from PyQt4 import QtCore, QtGui class Ui_Dialog(object): def setupUi(self, Dialog): Dialog.setObjectName("Dialog") Dialog.resize(115, 160) sizePolicy = QtGui.QSizePolicy(QtGui.QSizePolicy.Fixed, QtGui.QSizePolicy.Fixed) sizePolicy.setHorizontalStretch(0) sizePolicy.setVerticalStretch(0) sizePolicy.setHeightForWidth(Dialog.sizePolicy().hasHeightForWidth()) Dialog.setSizePolicy(sizePolicy) Dialog.setMinimumSize(QtCore.QSize(115, 160)) Dialog.setMaximumSize(QtCore.QSize(115, 160)) self.verticalLayout = QtGui.QVBoxLayout(Dialog) self.verticalLayout.setObjectName("verticalLayout") self.label = QtGui.QLabel(Dialog) font = QtGui.QFont() font.setFamily("Andale Mono") font.setPointSize(72) self.label.setFont(font) self.label.setObjectName("label") self.verticalLayout.addWidget(self.label) self.label_2 = QtGui.QLabel(Dialog) self.label_2.setObjectName("label_2") self.verticalLayout.addWidget(self.label_2) self.retranslateUi(Dialog) QtCore.QMetaObject.connectSlotsByName(Dialog) def retranslateUi(self, Dialog): Dialog.setWindowTitle(QtGui.QApplication.translate("Dialog", "Dialog", None, QtGui.QApplication.UnicodeUTF8)) self.label.setText(QtGui.QApplication.translate("Dialog", "UGLY", None, QtGui.QApplication.UnicodeUTF8)) self.label_2.setText(QtGui.QApplication.translate("Dialog", "Not ugly", None, QtGui.QApplication.UnicodeUTF8)) 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_()) 

2. No more constraint on size: the label with font size 72 can be displayed.

    from PyQt4 import QtCore, QtGui class Ui_Dialog(object): def setupUi(self, Dialog): Dialog.setObjectName("Dialog") Dialog.resize(495, 140) self.verticalLayout = QtGui.QVBoxLayout(Dialog) self.verticalLayout.setObjectName("verticalLayout") self.label = QtGui.QLabel(Dialog) font = QtGui.QFont() font.setFamily("Andale Mono") font.setPointSize(72) self.label.setFont(font) self.label.setObjectName("label") self.verticalLayout.addWidget(self.label) self.label_2 = QtGui.QLabel(Dialog) self.label_2.setObjectName("label_2") self.verticalLayout.addWidget(self.label_2) self.retranslateUi(Dialog) QtCore.QMetaObject.connectSlotsByName(Dialog) def retranslateUi(self, Dialog): Dialog.setWindowTitle(QtGui.QApplication.translate("Dialog", "Dialog", None, QtGui.QApplication.UnicodeUTF8)) self.label.setText(QtGui.QApplication.translate("Dialog", "less UGLY", None, QtGui.QApplication.UnicodeUTF8)) self.label_2.setText(QtGui.QApplication.translate("Dialog", "Not ugly", None, QtGui.QApplication.UnicodeUTF8)) 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_())