Binding not firing

Question

I am writing a Universal app. I have a dto (MobileProject) that has several properties, one of which is ShortName.
In my ViewModel, I have a property (SelectedProject) to hold which item is bound to the SelectedItem in the ComboBox.
        private MobileProject _selectedProject;
        [RestorableState]
        public MobileProject SelectedProject
            get { return _selectedProject; }
            set
                if (value != null)
                    CanSave = (!string.IsNullOrEmpty(value.ShortName));
                SetProperty(ref _selectedProject, value);
        <ComboBox x:Uid="ProjectList"
                      Header="Projects"
                      PlaceholderText="select a project" 
                      ItemsSource="{Binding Source={StaticResource lvProjects}}"
                      SelectedItem="{Binding SelectedProject, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
                      DisplayMemberPath="ShortName" />
        <TextBox x:Uid="ProjectName"
                     Header="Project Name"
                     PlaceholderText="required"                    
                     Text="{Binding SelectedProject.ShortName, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"/>
My ComboBox happily lists all my projects, and when I select one, the textbox is updated. However, when I overwrite the text in the TextBox,
the SelectedProject property is not being notified in the ViewModel of the text change, so CanSave is not being set via SelectedProject, therefore my
button which is bound to the CanSave property never gets enabled when I type a ShortName. As far as I can see, everything looks fine.
If I override the CanSave so the button is enabled, when I click the button and check the selectedProject properties, the ShortName reflects my changes.
How can I get the SelectedProject property to fire when I'm typing my changes into the TextBox?

Answer 1

Thanks for your code, however I think you post the question in  a incorrect forum, this is Windows Store app forum instead of a WPF forum. Actually there are some difference between WPF and Windows Store App on XAML, I'm afraid I may give you wrong
direction.
If you would like to get more sufficient suggestion, you can post a new question at
https://social.msdn.microsoft.com/Forums/vstudio/en-US/home?forum=wpf
--James
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