Question

I am creating a project using WPF and MVVM-Light library from GalaSoft. I will have a base abstract View Model class, which will be used by all other View Model classes implemented. There I will have MVVM-Light base class as my base class. However, inside this base class, when I try to use RaisePropertyChanged function I get the following error:

An object reference is required for the non-static field, method, or property ‘GalaSoft.MvvmLight.ViewModelBase.RaisePropertyChanged(string)’

The code will look like this:

AnalysisViewModelBase : ViewModelBase
{
    public const string TagDescriptionStringListPropertyName = "TagDescriptionStringList";

    protected static List<string> m_tagDescriptionStringList;

    public static List<string> TagDescriptionStringList 
    { 
        get 
        { return m_tagDescriptionStringList; }
        set
        {
            if (m_tagDescriptionStringList == value)
                return;

            m_tagDescriptionStringList = value;

            RaisePropertyChanged(TagDescriptionStringListPropertyName);
        }

    }
    protected AnalysisViewModelBase()
    {
        m_tagDescriptionStringList = new List<string>();

        m_tagDescriptionStringList.AddRange(new string[] { "North Position", "East Position", "Depth" });
    }
}

AnotherViewModel : AnalysisViewModelBase
{ ... }

Could anyone please help me understand what is wrong with my RaiseProperyChanged function?

Answer 1

You are trying to access a Non Static Method From a Static Method… It does not have access to this value, you have to make your method non static.

here is a web page which explains about static methods if you want to have a better understanding of why you can’t do what you are trying to do.

Link