以下是
QLabel从此处发布的解决方案衍生出来的解决方案：https : //forum.qt.io/topic/36088/automatically-scale-
text-in-qlabels/5。
这包括
resizeEvent方法的重新实现，其中
QLabel根据的大小更新的字体大小
contentRect。请注意，必须
sizePolicy将Qlabel的设置
Ignored为此才能正常工作。
import sysfrom PyQt4 import QtGuiclass myQLabel(QtGui.QLabel): def __init__(self, *args, **kargs): super(myQLabel, self).__init__(*args, **kargs) self.setSizePolicy(QtGui.QSizePolicy(QtGui.QSizePolicy.Ignored, QtGui.QSizePolicy.Ignored)) self.setMinSize(14) def setMinSize(self, minfs): f = self.font() f.setPixelSize(minfs) br = QtGui.QFontMetrics(f).boundingRect(self.text()) self.setMinimumSize(br.width(), br.height()) def resizeEvent(self, event): super(myQLabel, self).resizeEvent(event) if not self.text(): return #--- fetch current parameters ---- f = self.font() cr = self.contentsRect() #--- find the font size that fits the contentsRect --- fs = 1 while True: f.setPixelSize(fs) br = QtGui.QFontMetrics(f).boundingRect(self.text()) if br.height() <= cr.height() and br.width() <= cr.width(): fs += 1 else: f.setPixelSize(max(fs - 1, 1)) # backtrack break #--- update font size --- self.setFont(f)class myApplication(QtGui.QWidget): def __init__(self, parent=None): super(myApplication, self).__init__(parent) #---- Prepare a Layout ---- grid = QtGui.QGridLayout() for i in range(3): grid.addWidget(myQLabel('some text'), i, 0) grid.setRowStretch(i, i+1) grid.setRowMinimumHeight(i, 25) self.setLayout(grid) self.resize(500, 300)if __name__ == '__main__': app = QtGui.QApplication(sys.argv) instance = myApplication() instance.show() sys.exit(app.exec_())结果是：
更新-resizeEvent的优化：
下面是该
resizeEvent方法的优化版本，应该可以产生更好的性能。它大大减少了寻找最佳字体大小值所需的迭代次数。我还没有进行广泛的测试。
def resizeEvent(self, event): super(myQLabel, self).resizeEvent(event) if not self.text(): return #--- fetch current parameters ---- f = self.font() cr = self.contentsRect() #--- iterate to find the font size that fits the contentsRect --- dw = event.size().width() - event.oldSize().width() # width change dh = event.size().height() - event.oldSize().height() # height change fs = max(f.pixelSize(), 1) while True: f.setPixelSize(fs) br = QtGui.QFontMetrics(f).boundingRect(self.text()) if dw >= 0 and dh >= 0: # label is expanding if br.height() <= cr.height() and br.width() <= cr.width(): fs += 1 else: f.setPixelSize(max(fs - 1, 1)) # backtrack break else: # label is shrinking if br.height() > cr.height() or br.width() > cr.width(): fs -= 1 else: break if fs < 1: break #--- update font size --- self.setFont(f)
