Depending on your end goal, you might want to consider using a library like OpenCV to do the zooming part and Qt to display the result.

@alan02011114
I don't understand what your question is. As the error message tells you, your slot requires a dfreceived/second position argument and you are not supplying it in your lambda so you get the error.

@Pythonic-person said in Widgets with SizePolicy there is no effects:

Do you mean taking the main window size and then change the widget size with the code?

You either use one of the provided layout mechanisms, develop you your only layout implementation, or you do all the resizing of contained widgets yourself 1990's style.

If you wish to do it yourself then you need to override the resizeEvent() of the container widget and resize the contained widgets yourself using whatever logic you see fit.

@CEO said in How to display QTableWidget selected row in a qLineEdit of the same class?:

@JonB now I discovered you are either hoarding knowledge or might not have done any work on the question.

Yes, you're right. I have nothing better to do than lie to questioners about what I know and they should do, and I don't spend enough of my time writing the code demanded to save them time.

Here is an extract from my usage of the QDataWidgetMapper which I know nothing about from a sample project of mine. I'm sorry if my variables/widgets/model are not the same as yours. Also here I happen to be binding to QSpinBoxes, let me know if I need to change it to QLineEdits for you.

void SectorRegisters::initDataWidgetMapper() { // set up the `QDataWidgetMapper` this->dwm = new QDataWidgetMapper(this); // set model (this->sectorsModel is the model being used, in my case it's a `QStandardItemModel`) SectorsModel *sectorsModel = this->sectorsModel; dwm->setModel(sectorsModel); // Vertical => widget mapped to row dwm->setOrientation(Qt::Vertical); // current index is always column #0 dwm->setCurrentIndex(0); // Region mappings dwm->addMapping(ui->spinRegionSocialState, SectorsModel::RegionSocialState); dwm->addMapping(ui->spinRegionGoodAreas, SectorsModel::RegionGoodAreas); dwm->addMapping(ui->spinRegionPoorAreas, SectorsModel::RegionPoorAreas); dwm->addMapping(ui->spinRegionCash, SectorsModel::RegionCash); // Here there are many further widget<->model-column mappings // ... }

You're welcome.

Did you consider using the QtGraphicalEffects module ?

@Lalremruata said in How to avoid Null or empty value in QLineedit of Pyqt5:

even the self.lineEdit_2 is empty.

Are you really 100% sure? I used PyQt5 and I'm pretty sure self.lineEdit_2.text() == "" would work as expected. Get rid of all your other code and behaviour and check just this in a tiny program?

@jsulm

You should rather use https://doc.qt.io/qt-5/qstring.html#isEmpty

My understanding is PyQt5's QLineEdit.text() returns a Python str rather than a C++ QString anyway. I never found using QString methods of any use in PyQt5.

thanks guy I get my goal by the other way

@Pl45m4 no but I don't know how to do that sizeHint() can return the right size in a layout.and I have a valid parent.

@SGaist ok I see, but I still can't get the size after layout(this return QtCore.QSize())

self.graphicsView_3.adjustSize() print(self.graphicsView_3.size())

full code

from PyQt5 import QtCore, QtGui, QtWidgets from PhotoViewer import PhotoViewer class Ui_MainWindow(object): def setupUi(self, MainWindow): MainWindow.setObjectName("MainWindow") MainWindow.resize(800, 600) self.centralwidget = QtWidgets.QWidget(MainWindow) self.centralwidget.setObjectName("centralwidget") self.gridLayout = QtWidgets.QGridLayout(self.centralwidget) self.gridLayout.setObjectName("gridLayout") self.graphicsView_2 = QtWidgets.QGraphicsView(self.centralwidget) self.graphicsView_2.setObjectName("graphicsView_2") self.gridLayout.addWidget(self.graphicsView_2, 2, 0, 1, 1) self.graphicsView = QtWidgets.QGraphicsView(self.centralwidget) self.graphicsView.setObjectName("graphicsView") self.gridLayout.addWidget(self.graphicsView, 1, 0, 1, 1) self.graphicsView_3 = PhotoViewer(self.centralwidget) self.graphicsView_3.adjustSize() print(self.graphicsView_3.size()) self.graphicsView_3.setObjectName("graphicsView_3") self.gridLayout.addWidget(self.graphicsView_3, 1, 1, 1, 1) self.graphicsView_4 = QtWidgets.QGraphicsView(self.centralwidget) self.graphicsView_4.setObjectName("graphicsView_4") self.gridLayout.addWidget(self.graphicsView_4, 2, 1, 1, 1) MainWindow.setCentralWidget(self.centralwidget) self.menubar = QtWidgets.QMenuBar(MainWindow) self.menubar.setGeometry(QtCore.QRect(0, 0, 800, 25)) self.menubar.setObjectName("menubar") MainWindow.setMenuBar(self.menubar) self.statusbar = QtWidgets.QStatusBar(MainWindow) self.statusbar.setObjectName("statusbar") MainWindow.setStatusBar(self.statusbar) self.retranslateUi(MainWindow) QtCore.QMetaObject.connectSlotsByName(MainWindow) def retranslateUi(self, MainWindow): _translate = QtCore.QCoreApplication.translate MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow")) if __name__ == "__main__": import sys app = QtWidgets.QApplication(sys.argv) MainWindow = QtWidgets.QMainWindow() ui = Ui_MainWindow() ui.setupUi(MainWindow) MainWindow.show() sys.exit(app.exec_())

You should try to comment on the GItHub issue to see if you can get more details of how it was done ?

@JonB Thank you for interactions. Would you please show me an exact code of for example a PushButton and where to implement it. I am advanced python coder, I just need to see exact steps. Thank you very much.

@KroMignon Well, i try to learn from anothers in every forum, sorry :), @jsulm Thank you Sir, you are a Life saver :)

@Stainopel
None of this seems relevant. Either you don't really want separate applications but just one and you just want to show the other widget. Or, to run another application as you ask, use Qt's QProcess, or the Python ones for running sub-processes if you prefer, called from your button clicked slot.

@JonB Very Good Suggestion, I used a second variable in the other function to read the opened file(s) from the first function and it did work like a charm. Thanks. Here is an update to the code

def encryption_hash(self,comboBox_2): index = self.comboBox_2.currentIndex() path = self.fname_E with open(path, 'rb') as f: if index == 2: hasher1 = hashlib.md5() afile1 = f buf1 = afile1.read() a = hasher1.update(buf1) md5 =(str(hasher1.hexdigest())) self.lineEdit_E.setText("File Hash Using MD5: " + md5)

@Pl45m4 yes I initially used a line edit but ended up changing it to a qtextedit instead. Then using the documentation I was able to get the expected results

Hello, @JonB, thanks a lot for your reply. Yes, this is exactly what I meant.
Sorry for being unclear before.

@hcroope
For PyQt question you might ask at: https://riverbankcomputing.com/mailman/listinfo/pyqt

@Marek-Stocki
Wait, wait! You absolutely do not want to move a Python3 application back to Python2! Trust me :)

Even 26 seconds startup is quite unacceptable. Start up should be like ~1 second!! There is something wrong.....