Question

Why this code show me a window without image? I try to use QByteArray instead of StringIO, but i have same result. Anyone know answer?

import sys
from PyQt4 import QtGui, QtCore
from StringIO import StringIO
class Example(QtGui.QWidget):
    def __init__(self):
        super(Example, self).__init__()
        self.initUI()

    def initUI(self):
        cs=StringIO()
        cs.write(open("image.jpeg",'rb').read())
        p = QtGui.QPixmap()
        p.loadFromData(cs.getvalue())
        lbl=QtGui.QLabel()
        lbl.setPixmap(p)
        layout = QtGui.QHBoxLayout(self)
        layout.addWidget(lbl)
        self.move(20, 30)
        self.setWindowTitle('Picture')
        self.show()


app = QtGui.QApplication(sys.argv)
ex = Example()
sys.exit(app.exec_())

UPDATE:
I need show image from StringIO (or any another object in RAM), because i downloading it with pycurl without saving to HDD.

UPDATE 2:
Added Layout using, like Petr Viktorin advised, but code still not working.

UPDATE 3:
@Petr Viktorin, this code work only when i want to display PNG file, but when image – Jpeg/jpg, i see empty form. Maybe problem in QPixmap?

UPDATE 4:
Tested with various images, but…
http://i39.tinypic.com/3535mqd.jpg Where problem?

Answer 1

You didn’t add the label to the mainwindow. The easiest solution is:

lbl=QtGui.QLabel(self)

And the proper solution is using some layout, so the window will have the appropriate size. Add this after lbl.setPixmap(p):

layout = QtGui.QHBoxLayout(self)
layout.addWidget(lbl)