tags:

views:

274

answers:

4

What do I have to change to the following code so that the background is red, neither of the 2 ways I tried worked:

alt text

XAML:

<Window x:Class="TestBackground88238.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Window1" Height="300" Width="300">
    <StackPanel>

        <TextBlock Text="{Binding Message}" Background="{Binding Background}"/>

        <TextBlock Text="{Binding Message}">
            <TextBlock.Background>
                <SolidColorBrush Color="{Binding Background}"/>
            </TextBlock.Background>
        </TextBlock>

    </StackPanel>
</Window>

Code Behind:

using System.Windows;
using System.ComponentModel;

namespace TestBackground88238
{
    public partial class Window1 : Window, INotifyPropertyChanged
    {

        #region ViewModelProperty: Background
        private string _background;
        public string Background
        {
            get
            {
                return _background;
            }

            set
            {
                _background = value;
                OnPropertyChanged("Background");
            }
        }
        #endregion

        #region ViewModelProperty: Message
        private string _message;
        public string Message
        {
            get
            {
                return _message;
            }

            set
            {
                _message = value;
                OnPropertyChanged("Message");
            }
        }
        #endregion



        public Window1()
        {
            InitializeComponent();
            DataContext = this;

            Background = "Red";
            Message = "This is the title, the background should be " + Background + ".";

        }

        #region INotifiedProperty Block
        public event PropertyChangedEventHandler PropertyChanged;

        protected void OnPropertyChanged(string propertyName)
        {
            PropertyChangedEventHandler handler = PropertyChanged;

            if (handler != null)
            {
                handler(this, new PropertyChangedEventArgs(propertyName));
            }
        }
        #endregion

    }
}

Update 1:

I tried Aviad's answer which didn't seem to work. I can do this manually with x:Name as shown here but I want to be able to bind the color to a INotifyPropertyChanged property, how can I do this?

alt text

XAML:

<Window x:Class="TestBackground88238.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Window1" Height="300" Width="300">
    <StackPanel>

        <TextBlock Text="{Binding Message}" Background="{Binding Background}"/>

        <TextBlock x:Name="Message2" Text="This one is manually orange."/>

    </StackPanel>
</Window>

Code Behind:

using System.Windows;
using System.ComponentModel;
using System.Windows.Media;

namespace TestBackground88238
{
    public partial class Window1 : Window, INotifyPropertyChanged
    {

        #region ViewModelProperty: Background
        private Brush _background;
        public Brush Background
        {
            get
            {
                return _background;
            }

            set
            {
                _background = value;
                OnPropertyChanged("Background");
            }
        }
        #endregion

        #region ViewModelProperty: Message
        private string _message;
        public string Message
        {
            get
            {
                return _message;
            }

            set
            {
                _message = value;
                OnPropertyChanged("Message");
            }
        }
        #endregion

        public Window1()
        {
            InitializeComponent();
            DataContext = this;

            Background = new SolidColorBrush(Colors.Red);
            Message = "This is the title, the background should be " + Background + ".";

            Message2.Background = new SolidColorBrush(Colors.Orange);

        }

        #region INotifiedProperty Block
        public event PropertyChangedEventHandler PropertyChanged;

        protected void OnPropertyChanged(string propertyName)
        {
            PropertyChangedEventHandler handler = PropertyChanged;

            if (handler != null)
            {
                handler(this, new PropertyChangedEventArgs(propertyName));
            }
        }
        #endregion

    }
}
+2  A: 

The Background property expects a Brush object, not a string. Change the type of the property to Brush and initialize it thus:

Background = new SolidColorBrush(Color.Red);
Aviad P.
that didn't seem to work for me, I posted the code above (update 1)
Edward Tanguay
A: 

I figured this out, it was just a naming conflict issue: if you use TheBackground instead of Background it works as posted in the first example. The property Background was interfering with the Window property background.

Edward Tanguay
+2  A: 

I recommend reading the following blog post about debugging data binding: http://beacosta.com/blog/?p=52

And for this concrete issue: If you look at the compiler warnings, you will notice that you property has been hiding the Window.Background property (or Control or whatever class the property defines).

Oliver Hanappi
yes, the compiler warning was how I discovered it, thanks for the link, good information there
Edward Tanguay
A: 

You can still use "Background" as the property name, as long as you give your window a name and use this name on the "Source" of the Binding.

Gustavo Cavalcanti