Save Position and Size of the Application Window and load it for the next time

developer_96

@artwaw tried again. Not working. With debug() after close i got some hexa values. If im loading it, i got nothing. So "" is the only output.

Christian Ehrlicher

@developer_96 said in Save Position and Size of the Application Window and load it for the next time:

So "" is the only output.

This means you load the data from the wrong location. Fix your settings as @artwaw already told you (and not only here in the forum)

artwaw

@developer_96 like @Christian-Ehrlicher said, loader returns empty string which means data is being read from different location.
I'd strongly suggest editing main.cpp file like I hinted. Afterwards you just use QSettings settings;.

developer_96

@artwaw @Christian-Ehrlicher i did it already. Modify the cpp like @artwaw said. It doesn't work. I mean if it would be a wrong location the fullscreen mode and the position mode wouldn't work too , or not ?

Regards

Christian Ehrlicher

When the settings object returns an empty QByteArray but you saved a non-empty one you have a typo somewhere. Esp. when the same works for windowState. Check your code!

developer_96

How can i check that it works for windowsState? I mean i commented out the windows state part and the fullscreen and positing changing is still working. If im going to commented out the geometry nothing is working.

@Christian-Ehrlicher Check more times there is no typo.

Hope you can help.

Christian Ehrlicher

Provide a minimal, compilable example.

artwaw

@developer_96 you can use qDebug() to output saved and loaded values to the console, then compare them visually.

developer_96

@Christian-Ehrlicher

main.cpp:

  QCoreApplication::setOrganizationName("MyCompany");
  QCoreApplication::setApplicationName("MyApp");
  QApplication oApp(arc, arv);

close event:

  QSettings settings("MyCompany", "MyApp");
  settings.setValue("geometry", saveGeometry());
  settings.setValue("windowState", saveState());
  settings.sync(); // forces to write the settings to storage
  event->accept();
qDebug() << saveGeometry();
  qDebug() << saveState();

constructor:

  QSettings settings("MyCompany", "MyApp");
  restoreGeometry(settings.value("geometry").toByteArray());
  restoreState(settings.value("windowState").toByteArray());
  qDebug() << settings.value("geometry").toByteArray();
  qDebug() << settings.value("windowState").toByteArray();

@artwaw i tried again with debug.
I got for geometry values, compared windows stats and geomtry. Same values in save and loaded.

artwaw

@developer_96 Please change QSettings invocation from QSettings settings("MyCompany", "MyApp"); to QSettings settings; in ctor and closeEvent()
if you have same values on save and load then this should work. I am out of ideas for now.

developer_96

oki i will try it and tell you.
Another question:
How it would work for a qwidget for example?

  settings.setValue("qwidgetclassname/geometry", saveGeometry());
  restoreGeometry(settings.value("qwidgetclassname/geometry").toByteArray());
``
Maybe like that ??

artwaw

@developer_96 for particular widget it doesn't matter how you name it, string can be anything as long as it's unique. You can group it, you can save series as arrays, QSettings is really powerful.
But if you think of saving and restoring particular widgets let me tell you, there is really only a few cases when you need to do that. Qt way is to put your widgets into layouts on the window class and let Qt figure out sizes and positions once you restore global settings and state.
What's worth saving is for example when you have widgets placed on QSplitter - then it's worth saving splitter params.
Or sizes of sections of the header in views, should you want to.

Saving and restoring every widget's state etc is counter productive, using layouts is the right way.

developer_96

@artwaw right thank you for this info. I have a qtsplitter for two textboxes. So if im going to enlarge one box the other box i going to be smaller. What I want is: If im going to enlarge the one box and close the application, the same size should be there for both boxes.

artwaw

@developer_96 Assuming you've done layouts right all you need to do is save/restore the splitter. I use that method in one of my projects, save/restore looks like this:

closeEvent(): settings.setValue("splitter",ui->splitter->saveState());

and i method loading the UI (can be ctor as well but this needs to be done once global state and geometry are restored):
ui->splitter->restoreState(settings.value("splitter").toByteArray());

Again - this works if you have your layouts done right. Otherwise it might work, it might not.

developer_96

@artwaw nice thank you it is working. Really sad that the other problem is not solved :/

artwaw

@developer_96 it must be something silly. From the code I work on currently:
closeEvent():

    QSettings settings;
    settings.setValue("geo",saveGeometry());
    settings.setValue("state",saveState());
    settings.setValue("splitter",ui->splitter->saveState());
    settings.sync();
    event->accept();

Ctor:

    QSettings settings;
    restoreGeometry(settings.value("geo").toByteArray());
    restoreState(settings.value("state").toByteArray());
    ui->splitter->restoreState(settings.value("splitter").toByteArray());

developer_96

@artwaw i solved it ! it was only the problem that i use the methods befor the setupUi method.
Thank you for your help !!

artwaw

@developer_96
Ah... happy you solved it.
Please don't forget to mark topic as solved!

Christian Ehrlicher

@developer_96 said in Save Position and Size of the Application Window and load it for the next time:

it was only the problem that i use the methods befor the setupUi method.

So when you would have posted a minimal, compilable example we would have seen this much earlier but you didn't want to...

enjoysmath

For those who still use PyQt5:

```

_windowStatesEnum = {
    0x00000000 : Qt.WindowNoState,          #		The window has no state set (in normal state).
    0x00000001 : Qt.WindowMinimized,        #		The window is minimized (i.e. iconified).
    0x00000002 : Qt.WindowMaximized,	      #      The window is maximized with a frame around it.
    0x00000004 : Qt.WindowFullScreen,	      #      The window fills the entire screen without any frame around it.
    0x00000008 : Qt.WindowActive,		      # The window is the active window, i.e. it has keyboard focus.        
}
    
def __setstate__(self, data):
    self.__init__()
    self.setGeometry(data['geometry'])
    self.setWindowState(self._windowStatesEnum[data['window state']])
    
def __getstate__(self):
    return {
        'geometry' : self.geometry(),
        'window state' : int(self.windowState()),
    }



**```
Some Qt5 types are pickleable, such as whatever is returned by .geometry().  For enum types this I find to be the simplest solution to over come that, except you might hide away the enum map in a tools file.  The above code goes inside a subclassed QMainWindow.  So you can pickle pretty much any class you want to except QApplication, and a few others.  So I just pickle the whole darn application.
```**