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POHelp with some very basic WPF databinding
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copied!<p>I'm new to WPF and trying a simple example of databinding, but it's not working. My window has a TextBlock, which I bound to a property of the window object. I declared the property in code. </p> <p>When running this, I see the correct value appearing in the TextBlock. There's also a button, which when clicked updates the property, except I don't see this affecting the TextBlock.</p> <p>I implemented the INotifyPropertyChanged correctly, as far as I'm able to determine. I also see, when debugging, that <em>something</em> has subscribed to the PropertyChanged event, except it doesn't seem to do anything.</p> <p>I have 2 questions:</p> <p>1) Why isn't this working as expected?</p> <p>2) Is there any easy way to debug during run-time what's causing this, without resorting to third-party tools? From my cursory knowledge, it seems to me the debugging support in WPF is sorely lacking.</p> <p>The XAML is (not including the "standard" XAML window element):</p> <pre><code><TextBlock Height="28" Name="label1" VerticalAlignment="Top" Text="{Binding Path=TheName}" Grid.Row="0" ></TextBlock> <Button Height="23" Name="button1" VerticalAlignment="Stretch" Grid.Row="1" Click="button1_Click"> Button </Button> </code></pre> <p>The code in the window class is:</p> <pre><code> public partial class Window1 : Window { protected MyDataSource TheSource { get; set; } public Window1() { InitializeComponent(); TheSource = new MyDataSource(); TheSource.TheName = "Original"; // This works this.label1.DataContext = this.TheSource; } private void button1_Click(object sender, RoutedEventArgs e) { TheSource.TheName = "Changed"; // This doesn't work } } public class MyDataSource : INotifyPropertyChanged { string thename; public string TheName { get { return thename; } set { thename = value; OnPropertyChanged(thename); } } public event PropertyChangedEventHandler PropertyChanged; protected void OnPropertyChanged(string name) { PropertyChangedEventHandler handler = PropertyChanged; if (handler != null) { handler(this, new PropertyChangedEventArgs(name)); } } } } </code></pre>

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