xcode - ContentView_Previews 中的结构和类
问题描述
我有一个结构:
struct Item: Identifiable {
let id = UUID()
var isComplete: Bool = false
}
也让 item: Item
还有一个类:
class Model: ObservableObject {
@Published var isOn: Bool = false
@Published var arr = [Item(isComplete: true), Item(isComplete: false), Item(isComplete: true), Item(isComplete: false), Item(isComplete: true), Item(isComplete: true)]
}
和@ObservedObject var 模型:模型
如何正确地将项目和模型放入 ContentView_Previews?
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView(
item: <#Item#>,
model: <#Model#>
)
}
}
我不知道下一步该怎么做:/
解决方案
为ContentView
. 但如果它看起来像这样:
struct ContentView: View {
var item: Item
@EnvironmentObject var model: Model
var body: some View {
// no matter what here
}
}
你可以这样写:
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView(item: Item(isComplete: false))
.environmentObject(Model())
}
}
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