X轴的垂直线iOS图表

Question

也许这是一个简单的问题，但我想知道如何在X轴上绘制垂直线，在iOS图表中绘制X轴上的上标签。 （见图，如红线）

更新：我正在使用的库是这个https://github.com/danielgindi/ios-charts

Answer 1

你可以，但你必须覆盖一些方法，例如在x轴渲染器中查看drawGridLine()和drawLabels()。

qazxsw poi为您提供了有关如何在ios-charts中绘制网格线的完整详细信息，了解它对编写自己的自定义将非常有帮助。

Answer 2

设置要获得红色线条的轴的主要刻度位置和次要刻度位置。请尝试使用以下为图表的x轴编写的示例代码。

drawGridLine

有一个快乐的编码.. !!

Answer 3

我设法通过覆盖

CPTXYAxisSet *axisSet = (CPTXYAxisSet *)graph.axisSet;
CPTXYAxis *x = axisSet.xAxis;   //Get the axis of the graph

// x and y axis line color
CPTMutableLineStyle *axisLineStyle = [CPTMutableLineStyle lineStyle];
axisLineStyle.lineWidth = 2.0f;
axisLineStyle.lineColor = [CPTColor whiteColor];  //Set color whatever you want

//Text Style for axis title
CPTMutableTextStyle *axisTextStyle = [[CPTMutableTextStyle alloc] init];
axisTextStyle.color = [CPTColor whiteColor];      //Set color whatever you want

// Line color
CPTMutableLineStyle *tickLineStyle = [CPTMutableLineStyle lineStyle];
tickLineStyle.lineColor = [CPTColor whiteColor];  //Set color whatever you want
tickLineStyle.lineWidth = 2.0f;

x.title = @"Title for the axis";
x.titleOffset = 50.0f;
x.axisLineStyle = axisLineStyle;                //axis line style
x.titleTextStyle = axisTextStyle;               //axis title text style
x.majorTickLineStyle = axisLineStyle;           //Major axis tick style which you wanted
x.minorTickLineStyle = axisLineStyle;           //Minor axis tick style
x.labelTextStyle = axisTextStyle;               //axis label text style
x.labelingPolicy = CPTAxisLabelingPolicyNone;   //axis labeling policy
x.tickDirection = CPTSignNegative;              //This will set the red lines below the x-axis as displayed in screenshot you have attached.

来绘制x轴下方的刻度线。此功能在x轴下方绘制标签，因此可以在那里绘制其他内容。例如我们想要的滴答声！

drawLabel

要使用自定义渲染器：

class XAxisRendererWithTicks: XAxisRenderer {

     override func drawLabel(context: CGContext, formattedLabel: String, x: CGFloat, y: CGFloat, attributes: [NSAttributedString.Key: Any], constrainedToSize: CGSize, anchor: CGPoint, angleRadians: CGFloat) {

         super.drawLabel(context: context, formattedLabel: formattedLabel, x: x, y: y, attributes: attributes, constrainedToSize: constrainedToSize, anchor: anchor, angleRadians: angleRadians)

         context.beginPath()

        context.move(to: CGPoint(x: x, y: y))
        context.addLine(to: CGPoint(x: x, y: self.viewPortHandler.contentBottom))

        context.strokePath()
     }
}

示例图片：请不要介意颜色，但我认为你理解我的意思。 ;）

let customXAxisRenderer = XAxisRendererWithTicks(viewPortHandler: self.chartView.viewPortHandler, xAxis: xAxis, transformer: self.chartView.getTransformer(forAxis: .left))

self.chartView.xAxisRenderer = customXAxisRenderer

希望这可以帮助！