在新版本中，我创建了一些图表时遇到了一些麻烦，前面的代码是：
func setChart(dataPoints: [String], values: [Double]) {
var dataEntries: [BarChartDataEntry] = []
for i in 0..<dataPoints.count {
let dataEntry = BarChartDataEntry(value: values[i], xIndex: i)
dataEntries.append(dataEntry)
}
let chartDataSet = BarChartDataSet(yVals: dataEntries, label: "Units Sold")
let chartData = BarChartData(xVals: months, dataSet: chartDataSet)
barChartView.data = chartData
}
您可以使用以下行传递值，例如数月的数组：
let chartData = BarChartData(xVals: months, dataSet: chartDataSet)
在新版本之后，实现相同图形的代码是：
func setChart(dataPoints: [String], values: [Double]) {
var dataEntries: [BarChartDataEntry] = []
for i in 0..<dataPoints.count {
let dataEntry = BarChartDataEntry(x: Double(i+2), y:values[i], data: months )
dataEntries.append(dataEntry)
}
let chartDataSet = BarChartDataSet(values: dataEntries, label: "Units Sold")
let chartData = BarChartData()
chartData.addDataSet(chartDataSet)
barChartView.data = chartData
}
我试了几个小时，但我找不到修改X轴值的方法，我希望有人可以帮助我，谢谢!!
我找到了解决方案，也许另一个可以更好地解决这个问题，而无需创建新类，这就是我发现的：
首先你需要创建一个新类，它将是你的格式化程序类并添加IAxisValueFormater接口，然后你使用方法stringForValue来自定义新值，它需要两个参数，第一个是实际值（你可以看到它像索引），第二个是值所在的轴。
import UIKit
import Foundation
import Charts
@objc(BarChartFormatter)
public class BarChartFormatter: NSObject, IAxisValueFormatter
{
var months: [String]! = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]
public func stringForValue(value: Double, axis: AxisBase?) -> String
{
return months[Int(value)]
}
}
现在，在setCharat（）函数开头的文件中，您必须为formatter类创建两个变量，为轴类创建一个变量：
let formato:BarChartFormatter = BarChartFormatter()
let xaxis:XAxis = XAxis()
接下来，在for循环结束时继续并将索引和轴传递给formatter变量：
formato.stringForValue(Double(i), axis: xaxis)
循环后将格式添加到轴变量：
xaxis.valueFormatter = formato
最后一步是将新的xaxisformatted添加到barChartView：
barChartView.xAxis.valueFormatter = xaxis.valueFormatter
这就是setChart（）函数中的所有其他行只是保持它们的位置，我希望它可以帮助你。
你好，我最近遇到了同样的问题并以这种方式解决了 -
class ViewController: UIViewController {
var months: [String]!
var unitsSold = [Double]()
weak var axisFormatDelegate: IAxisValueFormatter?
@IBOutlet var viewForChart: BarChartView!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
axisFormatDelegate = self
months = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]
unitsSold = [20.0, 4.0, 6.0, 3.0, 12.0, 16.0, 4.0, 18.0, 2.0, 4.0, 5.0, 4.0]
// setChart(_ dataPoints:months,_ forY: unitsSold)
setChart(dataEntryX: months, dataEntryY: unitsSold)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func setChart(dataEntryX forX:[String],dataEntryY forY: [Double]) {
viewForChart.noDataText = "You need to provide data for the chart."
var dataEntries:[BarChartDataEntry] = []
for i in 0..<forX.count{
// print(forX[i])
// let dataEntry = BarChartDataEntry(x: (forX[i] as NSString).doubleValue, y: Double(unitsSold[i]))
let dataEntry = BarChartDataEntry(x: Double(i), y: Double(forY[i]) , data: months as AnyObject?)
print(dataEntry)
dataEntries.append(dataEntry)
}
let chartDataSet = BarChartDataSet(values: dataEntries, label: "Units Sold")
let chartData = BarChartData(dataSet: chartDataSet)
viewForChart.data = chartData
let xAxisValue = viewForChart.xAxis
xAxisValue.valueFormatter = axisFormatDelegate
}
}
最后，只需添加委托的扩展名即可
extension ViewController: IAxisValueFormatter {
func stringForValue(_ value: Double, axis: AxisBase?) -> String {
return months[Int(value)]
}
}
通过这个链接https://medium.com/@skoli/using-realm-and-charts-with-swift-3-in-ios-10-40c42e3838c0#.minfe6kuk找出这个解决方案
正如许多人所说，您可以使用IAxisValueFormatter类型创建类或扩展，但您可以轻松使用以下方法，只需要3行：
self.chartView.xAxis.valueFormatter = DefaultAxisValueFormatter(block: {(index, _) in
return xStrings[Int(index)]
})
这是我的setChart（）函数，以防你们中的一些人发现我的一些自定义有趣：
func setChartView(entriesData: [entry]) {
var chartEntries: [ChartDataEntry] = []
var xStrings: [String] = []
let sortedentriesData = entriesData.sorted { (s1: entry, s2: entry) -> Bool in
return s1.timestamp < s2.timestamp
}
for (i, entry) in sortedentriesData.enumerated() {
let newEntry = ChartDataEntry(x: Double(i), y: entry.temperature)
chartEntries.append(newEntry)
let dateFormatter = DateFormatter()
dateFormatter.timeStyle = .medium
dateFormatter.dateStyle = .none
xStrings.append("\(dateFormatter.string(from: Date.init(timeIntervalSince1970: TimeInterval(entry.timestamp))))")
}
let set: LineChartDataSet = LineChartDataSet(values: chartEntries, label: "°C")
set.setColor(NSUIColor.blue, alpha: CGFloat(1))
set.circleColors = [NSUIColor.blue]
set.circleRadius = 3
set.mode = LineChartDataSet.Mode.cubicBezier
let data: LineChartData = LineChartData(dataSet: set)
self.chartView.xAxis.labelRotationAngle = -90
self.chartView.xAxis.valueFormatter = DefaultAxisValueFormatter(block: {(index, _) in
return xStrings[Int(index)]
})
self.chartView.xAxis.setLabelCount(xStrings.count, force: true)
self.chartView.data = data
}
entry是我创建的结构：
struct entry {
var timestamp: Int
var temperature: Double
}
如果要子类化图形，则实现上述建议的更简洁方法是在子类本身中实现IAxisValueFormatter协议
class CustomGraphView : LineChartView, ChartViewDelegate, IAxisValueFormatter {}
像这样...
public func stringForValue(_ value: Double, axis: Charts.AxisBase?) -> String
{
return "My X Axis Label Str"; // Return you label string, from an array perhaps.
}
然后在你的init（）
self.xAxis.valueFormatter = self;
最简单的解决方案：
barChartView.xAxis.valueFormatter = IndexAxisValueFormatter(values: months)
barChartView.xAxis.granularity = 1