How to assign the horizontal gradient to QLineEdit background

Question

The code creates a QLineEdit with the background gradient running from top to bottom. How to make the gradient to go from side to side (essentially turn the Vertical to Horizontal gradient used as background)?

    line = QtGui.QLineEdit()
    gradient = QtGui.QLinearGradient( QtCore.QRectF(line.rect()).topRight(), QtCore.QRectF(line.rect()).bottomRight() )  # top bottm
    gradient = QtGui.QLinearGradient( QtCore.QRectF(line.rect()).topLeft(), QtCore.QRectF(line.rect()).topRight() )  # top bottm

    gradient.setColorAt(0.0, QtGui.QColor("blue"))
    gradient.setColorAt(1.0, QtGui.QColor("red"))
    brush = QtGui.QBrush(gradient)
    palette = line.palette()
    palette.setBrush(QtGui.QPalette.Base, brush)
    line.setPalette(palette)
    line.show()

score 1 · Accepted Answer · answered May 02 '16 at 18:13

You were on the right track with letting the gradient go from the top-left to the top-right corner. The problem was that the QLineEdit did not yet have the final shape so its rect() was too large. If you set the gradient after line.show() it works. See my example below:

import sys
from PyQt4 import QtGui, QtCore

app = QtGui.QApplication(sys.argv)

line = QtGui.QLineEdit()
rect = QtCore.QRectF(line.rect())
print rect #  640 by 480 pixels

line.show()

rect = QtCore.QRectF(line.rect())
print rect # 200 by 21 pixels

horGradient = QtGui.QLinearGradient(rect.topLeft(), rect.topRight())
verGradient = QtGui.QLinearGradient(rect.topLeft(), rect.bottomLeft())

gradient = horGradient 

gradient.setColorAt(0.0, QtGui.QColor("blue"))
gradient.setColorAt(1.0, QtGui.QColor("red"))
brush = QtGui.QBrush(gradient)
palette = line.palette()
palette.setBrush(QtGui.QPalette.Base, brush)
line.setPalette(palette)

sys.exit(app.exec_())

How to assign the horizontal gradient to QLineEdit background

1 Answers1