#963 – A Color Selection Box Organized by Hue, part II

In part I, I included source code for generating a list of sample colors.

To bind to a generated color list, we can call ColorUtil.GenerateColorList and make the result available via a property.  In the code sample below, we generate a list of 4,096 colors (16 values for red, green and blue).

public partial class MainWindow : Window, INotifyPropertyChanged
{
    public MainWindow()
    {
        this.InitializeComponent();
        this.DataContext = this;

         ColorList = ColorUtil.GenerateColorList(16);
    }

    private List<ColorWithInfo> colorList;
    public List<ColorWithInfo> ColorList
    {
        get { return colorList; }
        protected set
        {
            colorList = value;
            RaisePropertyChanged("ColorList");
        }
    }

    // INotifyPropertyChanged
    public event PropertyChangedEventHandler PropertyChanged = delegate { };

    private void RaisePropertyChanged(string propName)
    {
        PropertyChanged(this, new PropertyChangedEventArgs(propName));
    }
}

In our XAML, we can create a simple ComboBox that binds to this list.  We set the ItemTemplate to display each color as a simple rectangle and the ItemsPanel as a WrapPanel with a fixed width.

    <ComboBox Margin="15" Height="30" Width="200"
                ItemsSource="{Binding ColorList}"
                ScrollViewer.HorizontalScrollBarVisibility="Disabled">
        <ComboBox.ItemTemplate>
            <DataTemplate>
                <Grid>
                    <Rectangle Height="55" Width="55">
                        <Rectangle.Fill>
                            <SolidColorBrush Color="{Binding Color}"/>
                        </Rectangle.Fill>
                    </Rectangle>
                </Grid>
            </DataTemplate>
        </ComboBox.ItemTemplate>
        <ComboBox.ItemsPanel>
            <ItemsPanelTemplate>
                <WrapPanel IsItemsHost="True" Orientation="Horizontal" Width="1000"/>
            </ItemsPanelTemplate>
        </ComboBox.ItemsPanel>
    </ComboBox>

Below is an image showing the ComboBox in action. Note that the colors are sorted by hue, given that the GenerateColorList method sorted the color values this way.

#962 – A Color Selection Box Organized by Hue, part I

Here’s some code that generates a spread of different colors.  (We’ll later bind a ComboBox to the generated list of colors).

    public class ColorWithInfo : IComparable
    {
        public Color Color { get; set; }

        public string Info
        {
            get { return string.Format("{0}/{1}/{2}", Color.R, Color.G, Color.B); }
        }

        public string HueSatBright
        {
            get { return string.Format("{0}/{1}/{2}", Hue, Saturation, Brightness); }
        }

        public float Hue
        {
            get { return System.Drawing.Color.FromArgb(Color.R, Color.G, Color.B).GetHue(); }
        }

        public float Saturation
        {
            get { return System.Drawing.Color.FromArgb(Color.R, Color.G, Color.B).GetSaturation(); }
        }

        public float Brightness
        {
            get { return System.Drawing.Color.FromArgb(Color.R, Color.G, Color.B).GetBrightness(); }
        }

        public int CompareTo(object obj)
        {
            ColorWithInfo cwiOther = obj as ColorWithInfo;

            // Sort by Hue, and then Saturation, and then Brightness
            if (this.Hue == cwiOther.Hue)
            {
                if (this.Saturation == cwiOther.Saturation)
                    return this.Brightness.CompareTo(cwiOther.Brightness);
                else
                    return this.Saturation.CompareTo(cwiOther.Saturation);
            }
            else
                return this.Hue.CompareTo(cwiOther.Hue);
        }
    }

    public static class ColorUtil
    {
        public static List<ColorWithInfo> GenerateColorList(int numValsPerColor)
        {
            List<ColorWithInfo> colorList = new List<ColorWithInfo>();

            // Create increment such that we start at 0, end at 255,
            // and have a total of numValsPerColor within that range.
            int delta = Convert.ToInt32(255.0 / ((double)numValsPerColor - 1.0));

            for (int r = 0; r < numValsPerColor; r++)
                for (int g = 0; g < numValsPerColor; g++)
                    for (int b = 0; b < numValsPerColor; b++)
                    {
                        ColorWithInfo cwi = new ColorWithInfo {
                            Color = Color.FromRgb((byte)(r * delta), (byte)(g * delta), (byte)(b * delta))};
                        colorList.Add(cwi);
                    }

            colorList.Sort();

            return colorList;
        }
    }

#549 – More Colors Than You Know What to Do With

Pantone provides a color matching system that includes a list of 2,058 colors (the Pantone Goe system) that you can select from when selecting colors for print or for online applications.

Below is the full set of Pantone Goe colors.  To use any of these colors in a WPF application, simply use the color eyedropper tool in Blend to select the color that you want.

#526 – Use Adobe Kuler to Create Color Themes

Adobe has created an online app, Adobe Kuler, that allows you to easily create sets of themed colors based on a starting color or an image.

You can create a set of colors starting with a single color by selecting the From a Color option and then selecting one of the rules.  (E.g. Analogous, Monochromatic, Triad, etc).

After you pick the rule, you can click and drag on the center circle (with double outline) to change the starting color.  You can also click on any of the other circles to effectively change the rule.

You can also generate a palette of colors by starting with a picture.  Here’s a set of colors based on a picture of my shed.

After Kuler generates the initial palette, you can  drag the little circles around to change which spots in the picture it uses to generate the palette.