OxyPlot：如何使用軸標簽格式化程序並顯示Y標簽？

Question

我正在使用Oxyplot為我的Xamarin.iOS項目繪制條形圖..

這是我的圖表目前看起來喜歡的

這里是x軸值而不是數字，我想顯示太陽，mon true，wed .....

我可以看到CategoryAxis有一個名為LabelFormatter的方法，它返回Func<double, string> ，但我該如何使用它？

還有為什么Y軸標簽沒有顯示？

public class MyClass
{
    /// <summary>
    /// Gets or sets the plot model that is shown in the demo apps.
    /// </summary>
    /// <value>My model.</value>
    public PlotModel MyModel { get; set; }

    /// <summary>
    /// Initializes a new instance of the <see cref="OxyPlotSample.MyClass"/> class.
    /// </summary>
    public MyClass()
    {

        var model = new PlotModel { Title = "ColumnSeries" };
        model.PlotAreaBorderColor = OxyColors.Transparent;
        // A ColumnSeries requires a CategoryAxis on the x-axis.

        model.Axes.Add(new CategoryAxis()
        {
            Position = AxisPosition.Bottom,
            MinorTickSize = 0,
            MajorTickSize = 0,
            //MajorGridlineStyle = LineStyle.Solid,
            //MinorGridlineStyle = LineStyle.Solid,
        });

        model.Axes.Add(new LinearAxis()
        {
            AxislineStyle = LineStyle.None,
            Position = AxisPosition.Left,
            MinorTickSize = 0,
            MajorTickSize = 0,
            MajorGridlineStyle = LineStyle.Solid,
            MinorGridlineStyle = LineStyle.Solid,
            Minimum = 0,
            Maximum = 400,
        });

        var series = new ColumnSeries();
        series.Items.Add(new ColumnItem() { Value = 200, Color = OxyColors.Orange});
        series.Items.Add(new ColumnItem(200));
        series.Items.Add(new ColumnItem(300));
        series.Items.Add(new ColumnItem(100));
        series.Items.Add(new ColumnItem(200));
        series.Items.Add(new ColumnItem(100));
        series.Items.Add(new ColumnItem(130));

        model.Series.Add(series);

        this.MyModel = model;
    }
}

Answer 1

要在軸上顯示標簽，您必須指定屬性MajorStep ，Oxyplot將僅繪制與主要步驟匹配的標簽。

model.Axes.Add(new LinearAxis()
{
    MajorStep = 10,
    Position = AxisPosition.Left,
    ...
});

要使用日期名稱修改標簽，可以使用DateTimeAxis而不是LinearAxis ：

model.Axes.Add(new DateTimeAxis()
{
    StringFormat = "ddd",
    Position = AxisPosition.Bottom,
    ...
});

如果您想要更自定義的內容，則必須使用LabelFormatter屬性。

編輯：

CategoryAxis中的標簽：

var categoryAxis = new CategoryAxis()
{
    Position = AxisPosition.Bottom,
    ...
};

categoryAxis.ActualLabels.Add("Mon");
categoryAxis.ActualLabels.Add("Tue");
categoryAxis.ActualLabels.Add("Wed");
categoryAxis.ActualLabels.Add("Thu");
categoryAxis.ActualLabels.Add("Fri");
categoryAxis.ActualLabels.Add("Sat");
categoryAxis.ActualLabels.Add("Sun");

Model.Axes.Add(categoryAxis);

CategoryAxis.ActualLabels是readOnly，因此您必須逐個添加項目。