In my view model, I have added DisplayAttributes to my properties, and would now like to bind the ToolTip property of my TextBox controls to the Description property of the DisplayAttribute.
I found this SO question which handles the reading of the description, but can't figure out how to populate the ToolTip using the calculated description.
This seems like a roundabout way to do this since WPF doesn't support this attribute and so you'll be entering the attributes into the view-model and the view-model will be looking them up. They could be in any internal format.
In any case, here is a demo of the problem as you've stated it. We add a Descriptions property to the class that the text boxes are bound to. That property is a dictionary that maps property names to descriptions, that is, attributes. In the static constructor for the view-model we look up all the attributes and populate the dictionary.
A small XAML file with two text boxes:
<Grid >
<StackPanel>
<TextBox Text="{Binding FirstName}" ToolTip="{Binding Descriptions[FirstName]}"/>
<TextBox Text="{Binding LastName}" ToolTip="{Binding Descriptions[LastName]}"/>
</StackPanel>
</Grid>
the code-behind:
DataContext = new DisplayViewModel();
and a rudimentary view-model with two properties:
public class DisplayViewModel
{
private static Dictionary<string, string> descriptions;
static DisplayViewModel()
{
descriptions = new Dictionary<string,string>();
foreach (var propertyName in PropertyNames)
{
var property = typeof(DisplayViewModel).GetProperty(propertyName);
var displayAttributes = property.GetCustomAttributes(typeof(DisplayAttribute), true);
var displayAttribute = displayAttributes.First() as DisplayAttribute;
var description = displayAttribute.Name;
descriptions.Add(propertyName, description);
}
}
public DisplayViewModel()
{
FirstName = "Bill";
LastName = "Smith";
}
public static IEnumerable<string> PropertyNames { get { return new[] { "FirstName", "LastName" }; } }
[Display(Name = "First Name")]
public string FirstName { get; set; }
[Display(Name = "Last Name")]
public string LastName { get; set; }
public IDictionary<string, string> Descriptions { get { return descriptions; } }
}
