Two way binding settings problem.
- by Jamie
Hi,
I am having a problem using two way binding with a listpicker. I am able to set the value using c# but not in the SelectedItem=".." in xaml. The binding is returning the correct value (and is a value in the listpicker) as i have texted it by assigning the text to a textblock.
When the page loads, the binding used on the listpicker causes a System.ArgumentOutOfRangeException
The code i am using to set it is:
// Update a setting value. If the setting does not exist, add the setting.
public bool AddOrUpdateValue(string key, Object value)
{
bool valueChanged = false;
try
{
// If new value is different, set the new value
if (settingsStorage[key] != value)
{
settingsStorage[key] = value;
valueChanged = true;
}
}
catch (KeyNotFoundException)
{
settingsStorage.Add(key, value);
valueChanged = true;
}
catch (ArgumentException)
{
settingsStorage.Add(key, value);
valueChanged = true;
}
catch (Exception e)
{
Console.WriteLine("Exception occured whilst using IsolatedStorageSettings: " + e.ToString());
}
return valueChanged;
}
// Get the current value of the setting, if not found, set the setting to default value.
public valueType GetValueOrDefault<valueType>(string key, valueType defaultValue)
{
valueType value;
try
{
value = (valueType)settingsStorage[key];
}
catch (KeyNotFoundException)
{
value = defaultValue;
}
catch (ArgumentException)
{
value = defaultValue;
}
return value;
}
public string WeekBeginsSetting
{
get
{
return GetValueOrDefault<string>(WeekBeginsSettingKeyName, WeekBeginsSettingDefault);
}
set
{
AddOrUpdateValue(WeekBeginsSettingKeyName, value);
Save();
}
}
And in the xaml:
<toolkit:ListPicker x:Name="WeekStartDay"
Header="Week begins on"
SelectedItem="{Binding Source={StaticResource AppSettings},
Path=WeekBeginsSetting,
Mode=TwoWay}">
<sys:String>monday</sys:String>
<sys:String>sunday</sys:String>
</toolkit:ListPicker>
The StaticResource AppSettings is a resource from a seperate .cs file.
<phone:PhoneApplicationPage.Resources>
<local:ApplicationSettings x:Key="AppSettings"></local:ApplicationSettings>
</phone:PhoneApplicationPage.Resources>
Thanks in advance
