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Arrays 在数据生成之前启动Swift View_Arrays_Swift_Swiftui - Fatal编程技术网

Arrays 在数据生成之前启动Swift View

Arrays 在数据生成之前启动Swift View,arrays,swift,swiftui,Arrays,Swift,Swiftui,我的问题是:我正在附加一个数组,该数组用作我的组件的参数。组件在附加任何内容之前启动。函数数组在填充之前返回 我有以下代码: struct ContentView: View { //This gets data from a Firebase db @ObservedObject var categories = getData() func getCards() -> [AnimatedCard] { var array = [Animate

我的问题是:我正在附加一个数组,该数组用作我的组件的参数。组件在附加任何内容之前启动。函数数组在填充之前返回

我有以下代码:

struct ContentView: View {

    //This gets data from a Firebase db
    @ObservedObject var categories = getData()

    func getCards() -> [AnimatedCard] {
        var array = [AnimatedCard]()
        for i in categories.datas{
            array.append(AnimatedCard(cardContentImage: "test1", cardContentTitle: i.name, itemHeight: 300,itemWidth: 300))
        }
        return array
    }

    var body: some View {
        CarouselView(views: self.getCards())
    }
}
  • Firebase部件的工作方式是在列表中显示
    i.name
  • CarouselView
    获取一组动画卡。这也在起作用
试试这个: 因此,只有在有数据的情况下才会出现

struct ContentView: View {

    //This gets data from a Firebase db
    @ObservedObject var categories = getData()

    func getCards() -> [AnimatedCard] {
        var array = [AnimatedCard]()
        for i in categories.datas{
            array.append(AnimatedCard(cardContentImage: "test1", cardContentTitle: i.name, itemHeight: 300,itemWidth: 300))
        }
        return array
    }

    var body: some View {
        Group {
            if self.categories.datas.count > 0 {
                CarouselView(views: self.getCards())
            }
        }
    }
}

您应该将条件嵌入到
组的
正文中,否则它将无法编译。