Setting Date and Time for QDateEdit and QTimeEdit

Question

Working on a QGIS plugin, I am struggling to save/load date and time values. Users can enter dates via QDateEdit widget and times via QTimeEdit widget. Values are then stored the following:

s = QgsSettings()

# Date
self.Isochrones_Date_setting = self.dlg.Isochrones_Date.date()
s.setValue("otp_plugin/Isochrones_Date", self.Isochrones_Date_setting)
    
# Time
self.Isochrones_Time_setting = self.dlg.Isochrones_Time.time()
s.setValue("otp_plugin/Isochrones_Time", self.Isochrones_Time_setting)

and shall be read by:

s = QgsSettings()

# Date
self.Isochrones_Date_setting = s.value("otp_plugin/Isochrones_Date", QtCore.QDateTime.currentDateTime())
self.dlg.Isochrones_Date.setDateTime(self.Isochrones_Date_setting)
        
# Time
self.Isochrones_Time_setting = s.value("otp_plugin/Isochrones_Time", '14:00:00')
self.dlg.Isochrones_Time.setDateTime(self.Isochrones_Time_setting)

However, loading saved values or getting default values fails. With this code I am getting the error

TypeError: setDateTime(self, Union[QDateTime, datetime.datetime]): argument 1 has unexpected type 'QDate'

What is the correct syntax, if not .setDateTime()? Or do I need to convert QDate to some other date before? If so, how?

Answer 1

Basically you have to use .setDate() for QDateEdit and .setTime() for QTimeEdit, not .setDateTime() and convert strings to QTime via QTime.fromString() or to QDate via QDate.fromString().

But: in this case it is a little more complicated, because QtCore.QDateTime.currentDateTime()) is in QDateTime-Format. So in this case, QDateEdit, has to be set using .setDateTime() but the stored setting from QDateEdit is in QDate-Format, so .setDate() has to be used. The simplest way to combine both possibilities, is to just use a try/except statement: it will always pick the stored one, if available, and only the standard one if no stored is available.

So the code would look like:

s = QgsSettings()

# Date
self.Isochrones_Date_setting = s.value("otp_plugin/Isochrones_Date", QtCore.QDateTime.currentDateTime())
try:
    self.dlg.Isochrones_Date.setDateTime(self.Isochrones_Date_setting) # Standard value
except:
    self.dlg.Isochrones_Date.setDate(self.Isochrones_Date_setting) # Stored value
        
# Time
self.Isochrones_Time_setting = s.value("otp_plugin/Isochrones_Time", QTime.fromString('14:00:00'))
self.dlg.Isochrones_Time.setTime(self.Isochrones_Time_setting)