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POWPF: binding to custom class property. PropertyChanged is fired but view does not update
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copied!<p>I have a custom class Spieltag containing a property SpieltagDaten (custom class). SPieltagDaten has a property called SpieleGespielt. I have set this property as target of a binding on textbox text-property. </p> <p>The binding works just fine as the initial value of the property is beeing displayed but when the property changes the textbox is not beeing updated. </p> <p>The PropertyChanged event is fired and the parameter is spelled correctly.</p> <p>This is what the code looks like:</p> <p>This is the textbox with binding:</p> <pre class="lang-xml prettyprint-override"><code><TextBlock Name="textBlockGespielt" Text="{Binding Path=MySpieltag.Daten, Converter={util:SpieltagDatenToStringConverter}, ConverterParameter=SpieleGespielt, UpdateSourceTrigger=PropertyChanged}" /> </code></pre> <p>In constructor of the window I set</p> <pre><code>this.DataContext = this; </code></pre> <p>This is the root-class of the model containing a property called Daten:</p> <pre><code>public class Spieltag : ModelBase { private ISpieltagDaten daten; public ISpieltagDaten Daten { get { return daten; } set { daten = value; Changed("Daten"); } } } </code></pre> <p>SpieltagDaten contains a property SpieleGespielt</p> <pre><code>public class SpieltagDaten : ModelBase, interfaces.ISpieltagDaten { private int _spieleGespielt; public Int32 SpieleGespielt { get { return _spieleGespielt; } set { _spieleGespielt = value; Changed("SpieleGespielt"); } } } </code></pre> <p>ModelBase implements INotifyPropertyChanged:</p> <pre><code>public class ModelBase: INotifyPropertyChanged { public event PropertyChangedEventHandler PropertyChanged = delegate { }; protected void Changed(String propertyName) { PropertyChangedEventHandler handler = PropertyChanged; if (handler != null) { handler(this, new PropertyChangedEventArgs(propertyName)); } } } </code></pre> <p>edit:</p> <p>I forget to post the Converter. It's derived from MarkupExtension so I can use it easy in xaml:</p> <pre><code>class SpieltagDatenToStringConverter : MarkupExtension, IValueConverter { private static SpieltagDatenToStringConverter _converter = null; public override object ProvideValue(IServiceProvider serviceProvider) { if (_converter == null) { _converter = new SpieltagDatenToStringConverter(); } return _converter; } public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) { ISpieltagDaten daten = (ISpieltagDaten)value; string res = String.Empty; string propertyName = parameter.ToString(); PropertyInfo pi = typeof(ISpieltagDaten).GetProperty(propertyName); if (pi != null) { res = pi.GetValue(daten,null).ToString(); } return res; } public object ConvertBack(object values, Type targetType, object parameter, System.Globalization.CultureInfo culture) { throw new NotImplementedException(); } } </code></pre> <p>The converter is beeing called on the initial setup of the model. <img src="https://i.stack.imgur.com/xEnot.jpg" alt="enter image description here"></p>

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