Sharing data between different ViewModels

Question

I\'m trying to develop an easy MVVM project that it has two windows:

1. The first window is a text editor, where I bind some properties such as FontSize

Answer 1

In MVVM, models are the shared data store. I would persist the font size in the OptionsModel, which implements INotifyPropertyChanged. Any viewmodel interested in font size subscribes to PropertyChanged.

class OptionsModel : BindableBase
{
    public int FontSize {get; set;} // Assuming that BindableBase makes this setter invokes NotifyPropertyChanged
}

In the ViewModels that need to be updated when FontSize changes:

internal void Initialize(OptionsModel model)
{
    this.model = model;
    model.PropertyChanged += ModelPropertyChanged;

    // Initialize properties with data from the model
}

private void ModelPropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)
{
    if (e.PropertyName == nameof(OptionsModel.FontSize))
    {
        // Update properties with data from the model
    }
}