[Qgis-developer] idea for settings

[Denis Rouzaud]

Hi all,

I just wanted to share an idea I had today. In my plugins, I always had 
the problem of never knowing the default values I had set for the 
settings (the info being spread all over the code files), and it was 
always a pain to change a default value (I had to search in all my files 
for all the calls for the setting in question).

So, I created a class with a fake inheritance of QSettings:

class MyPluginSettings():
     def __init__(self):
         self.settings = QSettings("MyPlugin","MyPlugin")

         self.defaultValue = {    "mySettingValue1" : 0,
                                 "SomeTextSetting" : "hello",
                                 "Value4" : 13
                             }

     def value(self,setting):
         if self.defaultValue.has_key(setting) is False:
             raise NameError('MyPlugin has no setting %s' % setting)
         return self.settings.value(setting,self.defaultValue.get(setting))

     def setValue(self,setting,value):
         if self.defaultValue.has_key(setting) is False:
             raise NameError('MyPlugin has no setting %s' % setting)
         self.settings.setValue(setting,value)


You set self.settings = MyPluginSettings() in your plugin, and when you 
do self.settings.value("mySettingValue1"), you don't need to specify the 
default value.
The class will raise an exception if you call for an undefined setting. 
This will avoid typos in settings calls and therefore multiple 
definitions of the same setting.


Don't know if it's useful for you, but I was quite happy with this 
solution....

Greetings,

Denis