将标签字体大小与PyQt中的布局同步

将标签字体大小与PyQt中的布局同步

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)