how to disable a button when a textbox becomes readonly? - wpf

Question

I have a button and text box inside a stackpanel, when text box gets readonly state then the button should disable, i want to do this in XAML only is there any way to do this?

Answer 1

The binding is easy to define but you need a converter to invert the boolean value. Since you want to enable (IsEnabled = true) the Button when the TextBox is not readonly (IsReadOnly = false).
XAML
<StackPanel>
<StackPanel.Resources>
<local:InvertBooleanConverter x:Name="invertBoolConverter"/>
</StackPanel.Resources>
<TextBox x:Name=textBox />
<Button IsEnabled={Binding IsReadOnly, ElementName=textBox, Converter={StaticResource invertBoolConverter}}/>
</StackPanel>
local is a namespace you define in your UserControl that points to the namespace of the InvertBooleanConverter
xmlns:local="clr-namespace:NamespaceOfTheInvertBooleanConverter"
Converter
public class InvertBooleanConverter: IValueConverter {
public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) {
bool currentValue = System.Convert.ToBoolean(value);
return !currentValue;
}
public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) {
bool currentValue = System.Convert.ToBoolean(value);
return !currentValue;
}
}

Answer 2

<StackPanel>
<TextBox x:Name="targetTB">Hello</TextBox>
<Button Content="Test Button">
<Button.Style>
<Style>
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=targetTB, Path=IsReadOnly}" Value="True">
<Setter Property="Button.IsEnabled" Value="False"></Setter>
</DataTrigger>
<DataTrigger Binding="{Binding ElementName=targetTB, Path=IsReadOnly}" Value="False">
<Setter Property="Button.IsEnabled" Value="True"></Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</Button.Style>
</Button>
</StackPanel>
try this, it can work as you need.