按列表 C# WPF 中的项目设置矩形宽度

Question

如何设置矩形的宽度，通过 C# 中的用户控件除以列表中 Items 的数量，使用 WPF 必须在代码后面而不是使用 Xaml：

public partial class UserControl1 : UserControl
{
    private List<Color> colours;

    private int Highest;
    private int Lowest;
    private int Median;
    public int Width {get; set;}
    private Data mydata;

    public Data data 
    { 
        get
        {
            return mydata;
        }
        set
        {
            mydata = value;
            BindData();
        }
    }


    public UserControl1()
    {
        colours = new List<Color>() { Colors.Red, Colors.White, Colors.Blue};

        InitializeComponent();

        if (Width == 0)
        {
            Width = 300;
        }
    }

    private void BindData()
    {
        //work out rectangle width
        Highest = Convert.ToInt32(mydata.Values.Max());
        Lowest = Convert.ToInt32(mydata.Values.Min());
        Median = Convert.ToInt32(mydata.Values.Average());

        foreach (double item in mydata.Values)
        {
            //create rectangle of width specified

            SetWidth();
        }
    }

    private void SetWidth()
    {
        //divide number of items in list by total to define Width
    }

    private Color GetColourFromValue(int totalNumber)
    {
        var numOfColours = colours.Count;

        if (totalNumber >= numOfColours)
        {
            return colours[totalNumber % numOfColours];
        }

        return colours[totalNumber]; 
    }

    private Color GetGradeColour(byte itemNumber, byte totalNumberItems, Color ItemColour)
    {
        byte multipler = (byte)(200 / totalNumberItems);

        byte a = (byte)((itemNumber + 1) * multipler);

        return Color.FromArgb(a, ItemColour.R, ItemColour.G, ItemColour.B);
    }

    private Rectangle CreateRectangle(double Value, int Width, Color ItemColor)//double value, width)
    {
        //create rectangle
        var rectangle = new Rectangle()
        {
            //Fill = new SolidColorBrush(ItemColor)
        };
        //give rectangle width
        return rectangle;
    }
}

Answer 1

如果您希望一组控件自动共享父级UserControl 的水平空间，请使用带有列的Grid 控件。这比手动尝试计算宽度要容易得多。

<Grid>
    <Grid.ColumnDefinitions>
        <ColumnDefinition/>
        <ColumnDefinition/>
        <ColumnDefinition/>
        <ColumnDefinition/>
    </Grid.ColumnDefinitions>
    <Rectangle Grid.Column="0"/>
    <Rectangle Grid.Column="1"/>
    <Rectangle Grid.Column="2"/>
    <Rectangle Grid.Column="3"/>
</Grid>

代码：

var grid = new Grid
{
    ColumnDefinitions =
        {
            new ColumnDefinition(),
            new ColumnDefinition(),
            new ColumnDefinition(),
            new ColumnDefinition()
        }
};
var rectangle1 = new Rectangle { Fill = Brushes.Blue };
rectangle1.SetValue(Grid.ColumnProperty, 0);
grid.Children.Add(rectangle1);
var rectangle2 = new Rectangle { Fill = Brushes.Red };
rectangle2.SetValue(Grid.ColumnProperty, 1);
grid.Children.Add(rectangle2);
var rectangle3 = new Rectangle { Fill = Brushes.Green };
rectangle3.SetValue(Grid.ColumnProperty, 2);
grid.Children.Add(rectangle3);
var rectangle4 = new Rectangle { Fill = Brushes.Yellow };
rectangle4.SetValue(Grid.ColumnProperty, 3);
grid.Children.Add(rectangle4);