WPF ToolTip does not update

Question

Assuming I have a simple class that represents a staff member

class Staff
{
    public string FirstName { get; set; }
    public string FamilyName { get; set         


        

Answer 1

This example shows how to add a tooltip to a grid that recalculates the tooltip on demand, when the user hovers over a cell in the grid.

This is useful if you have a huge grid with 10,000 items, and you want to update the grid continuously - but you don't want to update the tooltips continuously, as this is time consuming.

This example is for Infragistics, but the principle applies equally to other fine libraries such as DevExpress.

Xaml

ViewModel

public ICommand ToolTipHoverRefreshCommand => new DelegateCommand(() =>
{
    this.OnPropertyChanged(this.ToolTip);
});  

public string ToolTip
{
    get
    {
        return DateTime.Now.ToString();
    }
    set
    {
        this.OnPropertyChanged(nameof(this.ToolTip));
    }
}