1
 2
 3
 4
 5
 6
 7
 8
 9
10
11

<lvc:CartesianChart 
    PressedCommand="{Binding PressedCommand}" 
    MovedCommand="{Binding MovedCommand}" 
    ReleasedCommand="{Binding ReleasedCommand}" 
    AnimationsSpeed="0:0:0.02" 
    EasingFunction="{x:Null}"
    Series="{Binding Series}"
    Sections="{Binding Sections}"
    XAxes="{Binding XAxes}"
    YAxes="{Binding YAxes}">
</lvc:CartesianChart>

 1
 2
 3
 4
 5
 6
 7
 8
 9
10

public Axis[] XAxes { get; set; } =
{
    new Axis
    {
        Name = "Crosshair",
        MinLimit = 0,
        MaxLimit = 10,
        Labeler = value => value.ToString("N2")
    }
};

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50

public RectangularSection[] Sections { get; set; } =
{
    new RectangularSection
    {
        Yi = 350,
        Yj = 350,
        Stroke = new SolidColorPaint
        {
            Color = SKColors.Red,
            StrokeThickness = 3,
            PathEffect = new LiveChartsCore.SkiaSharpView.Painting.Effects.DashEffect(new float[] { 6, 6 })
        }
    },
    new RectangularSection
    {
        LabelPaint = new SolidColorPaint { Color = SKColors.Blue.WithAlpha(20) },
        LabelSize=20,
        Label = "x2",
        Xi = 4,
        Xj = 6,
        Fill = new SolidColorPaint { Color = SKColors.Blue.WithAlpha(20) }
    },
    new RectangularSection
    {
        LabelPaint = new SolidColorPaint { Color = SKColors.Blue },
        LabelSize=20,
        Label = "x1",
        Xi = 1.2,
        Xj = 1.2,
        Stroke = new SolidColorPaint
        {
            Color = SKColors.Red,
            StrokeThickness = 3,
        },
    },
    new RectangularSection
    {
        LabelPaint = new SolidColorPaint { Color = SKColors.Blue },
        LabelSize=20,
        Label = "x2",
        Xi = 2.2,
        Xj = 2.2,
        Stroke = new SolidColorPaint
        {
            Color = SKColors.Red,
            StrokeThickness = 1,
            PathEffect = new LiveChartsCore.SkiaSharpView.Painting.Effects.DashEffect(new float[] { 6, 6 })
        },
    },
};

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58

[RelayCommand]
    private void Pressed(LiveChartsCore.Kernel.Events.PointerCommandArgs pointerCommandArgs)
    {        
        if (_rectangularSection != null)
        {
            var axes = XAxes.First();
            axes.CrosshairPaint = new SolidColorPaint(SKColors.Transparent, 1);
            axes.CrosshairLabelsPaint = new SolidColorPaint(SKColors.DarkRed, 1);
            axes.CrosshairLabelsBackground = SKColors.DarkOrange.AsLvcColor();
        }
    }

    [RelayCommand]
    private void Moved(LiveChartsCore.Kernel.Events.PointerCommandArgs pointerCommandArgs)
    {
        var chart = (ICartesianChartView<SkiaSharpDrawingContext>)pointerCommandArgs.Chart;
        var scaledPoint = chart.ScalePixelsToData(pointerCommandArgs.PointerPosition);
        var v = Sections.Where(s => s.Xi * 0.995 <= scaledPoint.X && s.Xi * 1.005 >= scaledPoint.X).ToList();

        var axes = XAxes.First();
        pressed = pointerCommandArgs.GetPressStatus();
        if (!pressed)
        {
            if (v.Count > 0)
            {
                _rectangularSection = v.First();
                Application.Current?.MainPage.SetCustomCursor(CursorIcon.SizeWestEast, Application.Current?.MainPage.Handler.MauiContext);
            }
            else
            {
                if (_rectangularSection != null)
                {
                    _rectangularSection = null;
                }
                Application.Current?.MainPage.SetCustomCursor(CursorIcon.Arrow, Application.Current?.MainPage.Handler.MauiContext);
            }
            axes.CrosshairPaint = null;
            axes.CrosshairLabelsPaint = null;
        }
        else
        {
            if (_rectangularSection != null && axes.MinLimit <= scaledPoint.X && scaledPoint.X <= axes.MaxLimit && Math.Abs((double)(scaledPoint.X - _rectangularSection.Xj)) >= 0.005)
            {
                _rectangularSection.Xi = _rectangularSection.Xj = scaledPoint.X;
            }
        }
    }

    [RelayCommand]
    private void Released(LiveChartsCore.Kernel.Events.PointerCommandArgs pointerCommandArgs)
    {
        if (_rectangularSection != null)
        {
            var axes = XAxes.First();
            axes.CrosshairPaint = null;
            axes.CrosshairLabelsPaint = null;
        }
    }