值已更改，但图表未迅速显示 [英] Value changed but the chart doesn't Swift

问题描述

我将Macaw框架用于图表.如果是第一次显示"X"，则只有一个问题.图表，它将始终(直到关闭应用程序)显示"X".图表.但是数据在变化(我在调试器中看到了).

I'm using the Macaw framework for my charts. There's only one problem that if it the first time shows the "X" chart, it will always(until closing app) show the "X" chart. But the data is changing(I saw it in the debugger).

这是我的"DahlichViewController"的摘要.

Here is the snippet of my "DahlichViewController".

class DahlichViewController: UIViewController {
    
@IBOutlet private var chartView: MacawChartView!
@IBOutlet weak var start: UIButton!
    
override func viewDidLoad() {
    super.viewDidLoad()
    chartView.backgroundColor = .clear
    chartView.contentMode = .scaleAspectFit
}

@IBAction func startPressed(_ sender: UIButton) {
    chartView.updateData(newData: createData())
    chartView.playAnimations()
}

这是我的MacawChartView.

And here's my MacawChartView.

import Foundation
import Macaw

class MacawChartView: MacawView {
    
    static var chartData = createData()
    
    static let maxValue              = 60
    static let maxValueLineHeight    = 18
    static let lineWidth: Double     = 275
    
    static let dataDivisor             = Double(maxValue/maxValueLineHeight)
    static let adjustedData: [Double]  = chartData.map({$0.percentage / dataDivisor})
    static var animations: [Animation] = []
    
    public func updateData(newData : [ElectionBrain])
    {
        MacawChartView.chartData = newData
        updateDisplay()
    }

    public func updateDisplay()
    {
        let chart = MacawChartView.createChart()
        self.node = Group(contents: [chart])
    }
    
    static func createChart() -> Group {
        var items: [Node] = addYAxisItems() + addXAxisItems()
        items.append(createBars())
        
        return Group(contents: items, place: .identity)
    }
    
    private static func addYAxisItems() -> [Node] {
        let maxLines            = 6
        let lineInterval        = Int(maxValue / maxLines)
        let yAxisHeight: Double = 200
        let lineSpacing: Double = 30
        
        var newNodes: [Node]    = []
        
        for i in 1...maxLines {
            let y = yAxisHeight - (Double(i) * lineSpacing)
            
            let valueLine = Line(x1: -5, y1: y, x2: lineWidth, y2: y).stroke(fill: Color.white.with(a: 0.10))
            let valueText = Text(text: "\(i * lineInterval)", align: .max, baseline: .mid, place: .move(dx: -10, dy: y))
            valueText.fill = Color.white
            
            newNodes.append(valueLine)
            newNodes.append(valueText)
        }
        
        let yAxis = Line(x1: 0, y1: 0, x2: 0, y2: yAxisHeight).stroke(fill: Color.white.with(a: 0.25))
        newNodes.append(yAxis)
        
        return newNodes
    }
    
    private static func addXAxisItems() -> [Node] {
        let chartBaseY: Double = 200
        var newNodes: [Node]   = []
        
        
        for i in 1...adjustedData.count {
            let x = (Double(i) * 50)
            let valueText = Text(text: chartData[i - 1].version, align: .max, baseline: .mid, place: .move(dx: x, dy: chartBaseY + 15))
            valueText.fill = Color.white
            newNodes.append(valueText)
        }
        
        let xAxis = Line(x1: 0, y1: chartBaseY, x2: lineWidth, y2: chartBaseY).stroke(fill: Color.white.with(a: 0.25))
        newNodes.append(xAxis)
        
        return newNodes
    }
    
    private static func createBars() -> Group {
        let fill  = LinearGradient(degree: 90, from: Color(val: 0xfff264), to: Color(val: 0xd69c00).with(a: 0.33))
        let items = adjustedData.map { _ in Group() }
        
        animations = items.enumerated().map { (i: Int, item: Group) in
            item.contentsVar.animation(delay: Double(i) * 0.1 ) { t in
                let height = adjustedData[i] * t * 10
                let rect   = Rect(x: Double(i) * 50 + 25, y: 200 - height, w: 30, h: height)
                return[rect.fill(with: fill)]
            }
        }
        
        return items.group()
    }
    
     func playAnimations() {
        MacawChartView.animations.combine().play()
    }

}

我将我的createData()函数声明为全局函数(不在VC中).问题在于数据在变化，而图表没有变化.所有时间都显示相同的图表.

I declared my createData() function as global function(Not in VC). The problem is that data is changing but the chart doesn't. It all time shows the same chart.

推荐答案

@Russel给我很好的建议.问题是我没有更新真正更新图表的adjustedData.我在updateDisplay中添加了此代码，它已经起作用了.

@Russel give me good advice. The problem was that I didn't update the adjustedData which truly updates the chart. I added this code in updateDisplay and it has worked.

        MacawChartView.adjustedData = MacawChartView.chartData.map({$0.percentage / MacawChartView.dataDivisor})

这篇关于值已更改，但图表未迅速显示的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！