Python PyQt4 functions to save and restore UI widget values?

Question

Before I attempt to write my own Python PyQt4 module functions... I wanted to ask if anyone has such a function to share.

In many of my python programs where I have a GUI built using PyQt4 and qtDesigner, I use the QSettings method to save and restore UI states and values of all widgets during close and startup.

This example shows how I save and restore some lineEdit, checkBox, and radioButton fields.

Does anyone have a function that can traverse the UI and find ALL widgets/controls and their states and save them (e.g. guisave()) and another function that can restore them (e.g. guirestore())?

My closeEvent looks something like this:

#---------------------------------------------
# close by x OR call to self.close
#---------------------------------------------

def closeEvent(self, event):      # user clicked the x or pressed alt-F4...

    UI_VERSION = 1   # increment this whenever the UI changes significantly

    programname = os.path.basename(__file__)
    programbase, ext = os.path.splitext(programname)  # extract basename and ext from filename
    settings = QtCore.QSettings("company", programbase)    
    settings.setValue("geometry", self.saveGeometry())  # save window geometry
    settings.setValue("state", self.saveState(UI_VERSION))   # save settings (UI_VERSION is a constant you should increment when your UI changes significantly to prevent attempts to restore an invalid state.)

    # save ui values, so they can be restored next time
    settings.setValue("lineEditUser", self.lineEditUser.text());
    settings.setValue("lineEditPass", self.lineEditPass.text());

    settings.setValue("checkBoxReplace", self.checkBoxReplace.checkState());
    settings.setValue("checkBoxFirst", self.checkBoxFirst.checkState());

    settings.setValue("radioButton1", self.radioButton1.isChecked());

    sys.exit()  # prevents second call

My MainWindow init looks something like this:

def __init__(self, parent = None):
    # initialization of the superclass
    super(QtDesignerMainWindow, self).__init__(parent)
    # setup the GUI --> function generated by pyuic4
    self.setupUi(self)

    #---------------------------------------------
    # restore gui position and restore fields
    #---------------------------------------------

    UI_VERSION = 1

    settings = QtCore.QSettings("company", programbase)    # http://pyqt.sourceforge.net/Docs/PyQt4/pyqt_qsettings.html

    self.restoreGeometry(settings.value("geometry"))
    self.restoreState(settings.value("state"),UI_VERSION) 

    self.lineEditUser.setText(str(settings.value("lineEditUser")))  # restore lineEditFile
    self.lineEditPass.setText(str(settings.value("lineEditPass")))  # restore lineEditFile

    if settings.value("checkBoxReplace") != None:
        self.checkBoxReplace.setCheckState(settings.value("checkBoxReplace"))   # restore checkbox
    if settings.value("checkBoxFirst") != None:
        self.checkBoxFirst.setCheckState(settings.value("checkBoxFirst"))   # restore checkbox

    value = settings.value("radioButton1").toBool()
    self.ui.radioButton1.setChecked(value)

Answer 1

OK, I wrote a module with 2 functions to do what I was asking for. Not really that complicated, once I figured it out, but it sure does save a lot of time whenever you create new pyqt gui programs where you want to save widget field values between sessions. I currently only have lineEdit, checkBox and combobox fields coded. If anyone else wants to add or improve (e.g. radio buttons...etc) ... I'm sure others, including myself, will appreciate it.

#===================================================================
# Module with functions to save & restore qt widget values
# Written by: Alan Lilly 
# Website: http://panofish.net
#===================================================================

import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *
import inspect

#===================================================================
# save "ui" controls and values to registry "setting"
# currently only handles comboboxes editlines & checkboxes
# ui = qmainwindow object
# settings = qsettings object
#===================================================================

def guisave(ui, settings):

    #for child in ui.children():  # works like getmembers, but because it traverses the hierarachy, you would have to call guisave recursively to traverse down the tree

    for name, obj in inspect.getmembers(ui):
        #if type(obj) is QComboBox:  # this works similar to isinstance, but missed some field... not sure why?
        if isinstance(obj, QComboBox):
            name   = obj.objectName()      # get combobox name
            index  = obj.currentIndex()    # get current index from combobox
            text   = obj.itemText(index)   # get the text for current index
            settings.setValue(name, text)   # save combobox selection to registry

        if isinstance(obj, QLineEdit):
            name = obj.objectName()
            value = obj.text()
            settings.setValue(name, value)    # save ui values, so they can be restored next time

        if isinstance(obj, QCheckBox):
            name = obj.objectName()
            state = obj.checkState()
            settings.setValue(name, state)

#===================================================================
# restore "ui" controls with values stored in registry "settings"
# currently only handles comboboxes, editlines &checkboxes
# ui = QMainWindow object
# settings = QSettings object
#===================================================================

def guirestore(ui, settings):

    for name, obj in inspect.getmembers(ui):
        if isinstance(obj, QComboBox):
            index  = obj.currentIndex()    # get current region from combobox
            #text   = obj.itemText(index)   # get the text for new selected index
            name   = obj.objectName()

            value = unicode(settings.value(name))  

            if value == "":
                continue

            index = obj.findText(value)   # get the corresponding index for specified string in combobox

            if index == -1:  # add to list if not found
                obj.insertItems(0,[value])
                index = obj.findText(value)
                obj.setCurrentIndex(index)
            else:
                obj.setCurrentIndex(index)   # preselect a combobox value by index    

        if isinstance(obj, QLineEdit):
            name = obj.objectName()
            value = unicode(settings.value(name))  # get stored value from registry
            obj.setText(value)  # restore lineEditFile

        if isinstance(obj, QCheckBox):
            name = obj.objectName()
            value = settings.value(name)   # get stored value from registry
            if value != None:
                obj.setCheckState(value)   # restore checkbox

        #if isinstance(obj, QRadioButton):                

################################################################

if __name__ == "__main__":

    # execute when run directly, but not when called as a module.
    # therefore this section allows for testing this module!

    #print "running directly, not as a module!"

    sys.exit() 

Answer 2

Here's an updated snippet which originally shared by mr. Panofish. Those great functions are same, but now can be used on never versions of PyQt and Python with minor changes if needed. Thx mr. Panofish, long live OpenSource! :)

Changes:

• Updated for Python3 and PyQt5
• Added geometry save\restore
• Added QRadioButton save\restore

• SetCheckState() replcaed with SetChecked() in order to avoid tristate

  def guisave(self):
  
    # Save geometry
      self.settings.setValue('size', self.size())
      self.settings.setValue('pos', self.pos())
  
      for name, obj in inspect.getmembers(ui):
        # if type(obj) is QComboBox:  # this works similar to isinstance, but missed some field... not sure why?
        if isinstance(obj, QComboBox):
            name = obj.objectName()  # get combobox name
            index = obj.currentIndex()  # get current index from combobox
            text = obj.itemText(index)  # get the text for current index
            settings.setValue(name, text)  # save combobox selection to registry
  
        if isinstance(obj, QLineEdit):
            name = obj.objectName()
            value = obj.text()
            settings.setValue(name, value)  # save ui values, so they can be restored next time
  
        if isinstance(obj, QCheckBox):
            name = obj.objectName()
            state = obj.isChecked()
            settings.setValue(name, state)
  
        if isinstance(obj, QRadioButton):
            name = obj.objectName()
            value = obj.isChecked()  # get stored value from registry
            settings.setValue(name, value)
  
  
  def guirestore(self):
  
    # Restore geometry  
    self.resize(self.settings.value('size', QtCore.QSize(500, 500)))
    self.move(self.settings.value('pos', QtCore.QPoint(60, 60)))
  
    for name, obj in inspect.getmembers(ui):
        if isinstance(obj, QComboBox):
            index = obj.currentIndex()  # get current region from combobox
            # text   = obj.itemText(index)   # get the text for new selected index
            name = obj.objectName()
  
            value = (settings.value(name))
  
            if value == "":
                continue
  
            index = obj.findText(value)  # get the corresponding index for specified string in combobox
  
              if index == -1:  # add to list if not found
                  obj.insertItems(0, [value])
                  index = obj.findText(value)
                  obj.setCurrentIndex(index)
              else:
                  obj.setCurrentIndex(index)  # preselect a combobox value by index
  
        if isinstance(obj, QLineEdit):
            name = obj.objectName()
            value = (settings.value(name).decode('utf-8'))  # get stored value from registry
            obj.setText(value)  # restore lineEditFile
  
        if isinstance(obj, QCheckBox):
            name = obj.objectName()
            value = settings.value(name)  # get stored value from registry
            if value != None:
                obj.setChecked(strtobool(value))  # restore checkbox
  
        if isinstance(obj, QRadioButton):
           name = obj.objectName()
           value = settings.value(name)  # get stored value from registry
           if value != None:
               obj.setChecked(strtobool(value))
  

Answer 3

thank you Panofish and everyone i am adding some update for QSlider/QSpinBox. it's small and simple.

at guisave you can add :

if isinstance(obj, QSpinBox):
    name  = obj.objectName()
    value = obj.value()             # get stored value from registry
    settings.setValue(name, value)

if isinstance(obj, QSlider):
    name  = obj.objectName()
    value = obj.value()             # get stored value from registry
    settings.setValue(name, value)

at guirestore you can add :

if isinstance(obj, QSlider):
    name = obj.objectName()
    value = settings.value(name)    # get stored value from registry
    if value != None:           
        obj. setValue(int(value))   # restore value from registry

if isinstance(obj, QSpinBox):
    name = obj.objectName()
    value = settings.value(name)    # get stored value from registry
    if value != None:
        obj. setValue(int(value))   # restore value from registry

Answer 4

I'm adding update for QListWidget.

In guisave:

if isinstance(obj, QListWidget):
    name = obj.objectName()
    settings.beginWriteArray(name)
    for i in range(obj.count()):
        settings.setArrayIndex(i)
        settings.setValue(name, obj.item(i).text())
    settings.endArray()

in guirestore:

if isinstance(obj, QListWidget):
    name = obj.objectName()
    size = settings.beginReadArray(name)
    for i in range(size):
        settings.setArrayIndex(i)
        value = settings.value(name)  # get stored value from registry
        if value != None:
            obj.addItem(value)
    settings.endArray()

Answer 5

Here is another version of this great code, that includes QTabWidget, and wrap everything into a class for easier use:

qt_utils.py:

from PyQt5 import QtGui
from PyQt5.QtWidgets import QComboBox, QCheckBox, QLineEdit,\
    QRadioButton, QSpinBox, QSlider, QListWidget, QTabWidget
from PyQt5.QtCore import QSettings
from distutils.util import strtobool

import inspect


class QMainWindow(QtGui.QMainWindow):
    companie_name = 'CompanieName'
    software_name = 'SoftwareName'
    settings_ui_name = 'defaultUiwidget'
    settings_ui_user_name = 'user'
    _names_to_avoid = {}

    def __init__(self, parent=None):
        super(QMainWindow, self).__init__(parent)
        self.settings = QSettings(self.companie_name, self.software_name)

    def closeEvent(self, e):
        self._gui_save()

    @classmethod
    def _get_handled_types(cls):
        return QComboBox, QLineEdit, QCheckBox, QRadioButton, QSpinBox, QSlider, QListWidget, QTabWidget

    @classmethod
    def _is_handled_type(cls, widget):
        return any(isinstance(widget, t) for t in cls._get_handled_types())

    def _gui_save(self):
        """
        save "ui" controls and values to registry "setting"
        :return:
        """
        name_prefix = f"{self.settings_ui_name}/"
        self.settings.setValue(name_prefix + "geometry", self.saveGeometry())

        for name, obj in inspect.getmembers(self):
            if not self._is_handled_type(obj):
                continue

            name = obj.objectName()
            value = None
            if isinstance(obj, QComboBox):
                index = obj.currentIndex()  # get current index from combobox
                value = obj.itemText(index)  # get the text for current index

            elif isinstance(obj, QTabWidget):
                value = obj.currentIndex()

            elif isinstance(obj, QLineEdit):
                value = obj.text()

            elif isinstance(obj, QCheckBox):
                value = obj.isChecked()

            elif isinstance(obj, QRadioButton):
                value = obj.isChecked()

            elif isinstance(obj, QSpinBox):
                value = obj.value()

            elif isinstance(obj, QSlider):
                value = obj.value()

            elif isinstance(obj, QListWidget):
                self.settings.beginWriteArray(name)
                for i in range(obj.count()):
                    self.settings.setArrayIndex(i)
                    self.settings.setValue(name_prefix + name, obj.item(i).text())
                self.settings.endArray()

            if value is not None:
                self.settings.setValue(name_prefix + name, value)

    def _gui_restore(self):
        """
        restore "ui" controls with values stored in registry "settings"
        :return:
        """

        name_prefix = f"{self.settings_ui_name}/"
        geometry_value = self.settings.value(name_prefix + "geometry")
        if geometry_value:
            self.restoreGeometry(geometry_value)

        for name, obj in inspect.getmembers(self):
            if not self._is_handled_type(obj):
                continue
            if name in self._names_to_avoid:
                continue

            name = obj.objectName()
            value = None
            if not isinstance(obj, QListWidget):
                value = self.settings.value(name_prefix + name)
                if value is None:
                    continue

            if isinstance(obj, QComboBox):
                index = obj.findText(value)  # get the corresponding index for specified string in combobox

                if index == -1:  # add to list if not found
                    obj.insertItems(0, [value])
                    index = obj.findText(value)
                    obj.setCurrentIndex(index)
                else:
                    obj.setCurrentIndex(index)  # preselect a combobox value by index

            elif isinstance(obj, QTabWidget):
                try:
                    value = int(value)
                except ValueError:
                    value = 0
                obj.setCurrentIndex(value)

            elif isinstance(obj, QLineEdit):
                obj.setText(value)

            elif isinstance(obj, QCheckBox):
                obj.setChecked(strtobool(value))

            elif isinstance(obj, QRadioButton):
                obj.setChecked(strtobool(value))

            elif isinstance(obj, QSlider):
                obj.setValue(int(value))

            elif isinstance(obj, QSpinBox):
                obj.setValue(int(value))

            elif isinstance(obj, QListWidget):
                size = self.settings.beginReadArray(name_prefix + name)
                for i in range(size):
                    self.settings.setArrayIndex(i)
                    value = self.settings.value(name_prefix + name)
                    if value is not None:
                        obj.addItem(value)
                self.settings.endArray()

    def _add_setting(self, name, value):
        name_prefix = f"{self.settings_ui_user_name}/"
        self.settings.setValue(name_prefix + name, value)

    def _get_setting(self, name):
        name_prefix = f"{self.settings_ui_user_name}/"
        return self.settings.value(name_prefix + name)

Here is an example of use:

import qt_utils


class MyMaine(qt_utils.QMainWindow, Ui_MainWindow):
    companie_name = 'Name'
    software_name = 'softName'
    _names_to_avoid = {'my_widget_name_not_to_save'}

    def __init__(self, parent=None):
        super(MyMaine, self).__init__(parent)

        self.setupUi(self)

        self._gui_restore()

Answer 6

I found these answers useful, so I thought I'd put them together and post a version (for PySide2/Qt5) with some duplication removed and a name provided to group the settings under.

from PySide2.QtWidgets import *
import inspect

def GetHandledTypes():
    return (QComboBox, QLineEdit, QCheckBox, QRadioButton, QSpinBox, QSlider, QListWidget)

def IsHandledType(widget):
    return any(isinstance(widget, t) for t in GetHandledTypes())

#===================================================================
# save "ui" controls and values to registry "setting"
#===================================================================

def GuiSave(ui : QWidget, settings : QSettings, uiName="uiwidget"):
    namePrefix = f"{uiName}/"
    settings.setValue(namePrefix + "geometry", ui.saveGeometry())

    for name, obj in inspect.getmembers(ui):
        if not IsHandledType(obj):
            continue

        name = obj.objectName()
        value = None
        if isinstance(obj, QComboBox):
            index = obj.currentIndex()  # get current index from combobox
            value = obj.itemText(index)  # get the text for current index

        if isinstance(obj, QLineEdit):
            value = obj.text()

        if isinstance(obj, QCheckBox):
            value = obj.isChecked()

        if isinstance(obj, QRadioButton):
            value = obj.isChecked()

        if isinstance(obj, QSpinBox):
            value = obj.value()

        if isinstance(obj, QSlider):
            value = obj.value()

        if isinstance(obj, QListWidget):
            settings.beginWriteArray(name)
            for i in range(obj.count()):
                settings.setArrayIndex(i)
                settings.setValue(namePrefix + name, obj.item(i).text())
            settings.endArray()
        elif value is not None:
            settings.setValue(namePrefix + name, value)

#===================================================================
# restore "ui" controls with values stored in registry "settings"
#===================================================================

def GuiRestore(ui : QWidget, settings : QSettings, uiName="uiwidget"):
    from distutils.util import strtobool

    namePrefix = f"{uiName}/"
    geometryValue = settings.value(namePrefix + "geometry")
    if geometryValue:
        ui.restoreGeometry(geometryValue)

    for name, obj in inspect.getmembers(ui):
        if not IsHandledType(obj):
            continue

        name = obj.objectName()
        value = None
        if not isinstance(obj, QListWidget):
            value = settings.value(namePrefix + name)
            if value is None:
                continue

        if isinstance(obj, QComboBox):
            index = obj.findText(value)  # get the corresponding index for specified string in combobox

            if index == -1:  # add to list if not found
                obj.insertItems(0, [value])
                index = obj.findText(value)
                obj.setCurrentIndex(index)
            else:
                obj.setCurrentIndex(index)  # preselect a combobox value by index

        if isinstance(obj, QLineEdit):
            obj.setText(value)

        if isinstance(obj, QCheckBox):
            obj.setChecked(strtobool(value))

        if isinstance(obj, QRadioButton):
            obj.setChecked(strtobool(value))

        if isinstance(obj, QSlider):
            obj.setValue(int(value))

        if isinstance(obj, QSpinBox):
            obj.setValue(int(value))

        if isinstance(obj, QListWidget):
            size = settings.beginReadArray(namePrefix + name)
            for i in range(size):
                settings.setArrayIndex(i)
                value = settings.value(namePrefix + name)
                if value is not None:
                    obj.addItem(value)
            settings.endArray()```

Answer 7

I'm a novice programmer so I'm not sure where I was going wrong and please excuse my lack of proper terminology/ technical understanding but my application has multiple QWidget classes for different app 'states' that load/ unload different UI's(and related functions) per state - all in and out of a single main 'QMainWindow'

this is using @beesleep class implementation but it looks like the code in question is the same for all the above examples

I was having issues with -

def _is_handled_type(cls, widget):
    return any(isinstance(widget, t) for t in cls._get_handled_types())


for name, obj in inspect.getmembers(self)
    # print(name) <------------------------------
    if not self._is_handled_type...

The methods of self "QMainWindow" are returned instead of all active child widgets.

.

My fix was this. I deleted - ***this part is not necessary, the code is just no longer used

@classmethod
def _is_handled_type(cls, widget):
    return any(isinstance(widget, t) fort in cls._get_handled_types())

Then changed in _gui_save() and _gui_restore() -

for name, obj in inspect.getmembers(self):
    if not self._is_handled_type(obj):
        continue
    if name in self._names_to_avoid: # _gui_restore()
        continue                     # _gui_restore()
        name = obj.objectName()
        value = None

To -

for child in self._get_handled_types():

    for obj in self.findChildren(child):

        if obj:

            name = obj.objectName()
            if name in self._names_to_avoid: # _gui_restore()
                continue                     # _gui_restore()
            value = None

The last step is that you have to assign a name to each object that you want to save

self.q_list = QListWidget()
self.q_list.setObjectName("List")
...
self.q_text = QLineEdit('enter text')
self.q_text.setObjectName("Text")

.

for child in self._get_handled_types():
    for obj in self.findChildren(child):
        if obj:
            name = obj.objectName()

            print(name, obj) <-------------

Returns

Text <PyQt5.QtWidgets.QLineEdit object at 0x0000023DD43E2708>
List <PyQt5.QtWidgets.QListWidget object at 0x0000023DD42530D8>

final note... if you want to see where the settings file is being saved then add - print(self.settings.fileName()) under the init

cheers!