在SwiftUI中,如何为条形图创建动态矩形?

时间:2019-07-18 17:48:34

标签: swiftui

我正在尝试创建一个自定义百分比条形图,如下图所示

enter image description here

但是,我无法以编程方式设置条宽度,我在做什么错了?

设置.frame(width:UIScreen.main.bounds.width * percent,height:23)会产生以下错误:对成员'frame(width:height:alignment :)'的引用不明确

import SwiftUI

struct BarChartView : View {
    @Binding var percent: Float

    init(percentage: Binding<Float>){
        self._percent = percentage
    }

    var body: some View {

            ZStack {
                Rectangle().fill(Color.yellow).frame(height: 30).border(Color.black, width:1)
                HStack {
                        RoundedRectangle(cornerRadius: 5)
                            .fill(Color.green).frame(width: 300, height:23).padding(2)
                    Spacer()
                }

                HStack {
                    Text("Bar Chart View").padding (2)
                    Spacer()
                    Text("\(String(format: "%02.f", arguments: [self.percent]))%")
                }

            }
        }

}

有没有一种方法可以确定ZStack中第一个矩形的宽度并计算出该百分比。我希望这也可以在横向模式下自动更新。

1 个答案:

答案 0 :(得分:2)

您可以使用GeometryReader来处理尺寸,但是在这种情况下,我认为使用形状更合适:

import SwiftUI

struct BarChartView : View {
    @Binding var percent: Float

    init(percentage: Binding<Float>){
        self._percent = percentage
    }

    var body: some View {

        HStack {
            Text("Bar Chart View").padding (5)
            Spacer()
            Text("\(String(format: "%02.f", arguments: [self.percent * 100]))%").padding(5)
        }
        .background(LeftPart(pct: CGFloat(percent)).fill(Color.green))
        .background(RightPart(pct: CGFloat(percent)).fill(Color.yellow))
        .padding(10)
    }

    struct LeftPart: Shape {
        let pct: CGFloat

        func path(in rect: CGRect) -> Path {
            var p = Path()
            p.addRoundedRect(in: CGRect(x: 0, y: 0, width: rect.size.width * pct, height: rect.size.height), cornerSize: .zero)
            return p
        }
    }

    struct RightPart: Shape {
        let pct: CGFloat

        func path(in rect: CGRect) -> Path {
            var p = Path()
            p.addRoundedRect(in: CGRect(x: rect.size.width * pct, y: 0, width: rect.size.width * (1-pct), height: rect.size.height), cornerSize: .zero)
            return p
        }
    }

}

struct ContentView: View {
    var body: some View {
        BarChartView(percentage: .constant(0.75))
    }
}