CODEWITHSUNDEEP
wpflistviewconverters
Christian
Christian

Reputation: 4375

How to display strings in a WPF ListView in different colours?

I would like to fill a WPF ListView with strings using a databinding. My code looks like this (and work! ;) ):

Xaml:

<ListView 
            ItemsSource="{Binding Entries}">
</ListView>

I left out some code for a better overview. Entries is an IList<string>.

So far, everything is working fine. Now comes the problem: A string in Entries may contain a particular keyword that indicates that this string wants to be displayed with red background inside the ListView. Say we have a method GetBackground(string s) which returns a Colour depending on the string.

How can I make the ListView display its items in the correct colour. My first idea was to have a converter converting my string to a colour using the abovementioned method. Where would I have to add this converter and how do I pass the string to the converter as parameter? my first Idea was:

<ListView
    ItemsSource="{Binding Entries, Converter={StaticResource entryToColourConverter}, 
ConverterParameter=???}"
</ListView>

Does anyone have an idea how this could be done? Am I on the right track?

Best wishes, Christian

EDIT 1: Changed the code (as a first step) towards:

<UserControl.Resources>
        <DataTemplate x:Key="entryTemplate">
            <TextBlock 
                Text="{Binding}"
                Background="Green"/>
        </DataTemplate>
</UserControl.Resources>

...

<ListView 
            ItemsSource="{Binding Entries}"
            ItemTemplate="{StaticResource entryTemplate}>
</ListView>

However, this does not work at all. Even if I change the text to some static value, the result is still the same as with the previous code.

EDIT 2: I found the problem, my code looked like this:

<ListView x:Name="lvEntries"
                  ItemTemplate="{StaticResource EntriesTemplate}"
                  ItemsSource="{Binding Entries, NotifyOnTargetUpdated=True}">

            <ListView.View>

                <GridView x:Name="gvEntries">
                    <GridViewColumn
                        HeaderContainerStyle="{StaticResource hcs}"
                        Header="Entry"
                        TextBlock.TextAlignment="Left">
                    </GridViewColumn>
                </GridView>
            </ListView.View>

        </ListView>

And this ListView.View was the problem. On removing that, everything was working! :) Now I have to find out how to solve this without the ListView.View

Upvotes: 3

Views: 3884

Answers (2)

David Masters
David Masters

Reputation: 8295

<Window.Resources>
    <local:EntryToBackgroundConverter x:Key="EntryToBackgroundConverter"/>
    <DataTemplate x:Key="EntryTemplate">
        <TextBlock Text="{Binding .}" Background="{Binding ., Converter={StaticResource EntryToBackgroundConverter}}"/>
    </DataTemplate>        
</Window.Resources>
<Grid>              
    <ListView ItemsSource="{Binding Entries}" ItemTemplate="{StaticResource EntryTemplate}"></ListView>        
</Grid>

Converter:

public class EntryToBackgroundConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        string stringValue = value as string;

        if (string.IsNullOrEmpty(stringValue))
            return Brushes.Black;

        if (stringValue == "foreach")
            return Brushes.Blue;
        if (stringValue == "if")
            return Brushes.Blue;

        return Brushes.Black;
    }

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        return value;
    }
}

You're on the right lines... something like this should work...

Upvotes: 4

Sergey Vedernikov
Sergey Vedernikov

Reputation: 7744

Create item template for ListView and then tie text color of (for example) label to Entrie property

Upvotes: 0

Related Questions