Wpf – PasswordBox with MVVM

mvvmpasswordboxwpf

Hi people stackoverflow. I'm working with MVVM, I have ViewModel call UserViewModel with a Property Password. In the View have a control PasswordBox.

<PasswordBox x:Name="txtPassword" Password="{Binding Password}" />

But this xaml don't work. How do you do the binding?? Help please!!

Best Answer

For security reasons the Password property is not a dependency property and therefore you can't bind to it. Unfortunately you'll need to perform the binding in the code behind the old fashioned way (register for OnPropertyChanged event and update the value through code...)

I quick search brings me to this blog post which shows how to write an attached property to sidestep the issue. Whether this is worth doing or not though really depends on your aversion to code-behind.

Related Solutions

C# – How should the ViewModel close the form

I was inspired by Thejuan's answer to write a simpler attached property. No styles, no triggers; instead, you can just do this:

<Window ...
        xmlns:xc="clr-namespace:ExCastle.Wpf"
        xc:DialogCloser.DialogResult="{Binding DialogResult}">

This is almost as clean as if the WPF team had gotten it right and made DialogResult a dependency property in the first place. Just put a bool? DialogResult property on your ViewModel and implement INotifyPropertyChanged, and voilà, your ViewModel can close the Window (and set its DialogResult) just by setting a property. MVVM as it should be.

Here's the code for DialogCloser:

using System.Windows;

namespace ExCastle.Wpf
{
    public static class DialogCloser
    {
        public static readonly DependencyProperty DialogResultProperty =
            DependencyProperty.RegisterAttached(
                "DialogResult",
                typeof(bool?),
                typeof(DialogCloser),
                new PropertyMetadata(DialogResultChanged));

        private static void DialogResultChanged(
            DependencyObject d,
            DependencyPropertyChangedEventArgs e)
        {
            var window = d as Window;
            if (window != null)
                window.DialogResult = e.NewValue as bool?;
        }
        public static void SetDialogResult(Window target, bool? value)
        {
            target.SetValue(DialogResultProperty, value);
        }
    }
}

I've also posted this on my blog.

C# – MVVM: Tutorial from start to finish

Your question really seems to be asking 2 questions:

Where are some good tutorials on WPF, assuming I have no previous WPF experience?
Where are some good tutorials on learning MVVM?

Some of these resources may be duplicated in previous answers...

Tutorials on WPF

A Guided Tour of WPF by Josh Smith

I wrote a series of introductory WPF articles on The Code Project. The goal of those articles is to bring someone with no WPF experience up-to-speed enough so that (s)he can fully understand how the series’ demo application works.
Bea Stollnitz (link is to her archives) has a number of great articles on WPF.
WPF: A Beginner's Guide - Part 1 of n by Sacha Barber
WindowsClient.net WPF Training Videos

MVVM Tutorials

WPF Apps With The Model-View-ViewModel Design Pattern by Josh Smith (duplicate link already provided by Yacoder)
Jason Dolinger's presentation on the Model-View-ViewModel (link to video embedded in article)
Dan Crevier's DataModel-View-ViewModel pattern series (similar to MVVM)

Composite WPF (Prism) Resources
Though not exactly what you asked, it is the natural progression with WPF and MVVM.

Best Answer

Related Solutions

C# – How should the ViewModel close the form

C# – MVVM: Tutorial from start to finish

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