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单击TableRow上下文菜单按钮时,SwiftUI警报视图不显示

alert core-data swiftui

JFS · 技术社区 · 1 年前

当用户要删除选定的表行时,我尝试显示一个警报视图。删除按钮是表格行上下文菜单的一部分。我认为这是因为表行不是视图,但当将警报移动到我无法访问的表视图时 secretItem 从ForEach循环中删除。因此,如何从上下文菜单按钮上具有警报视图的表中删除行(对象项)

有什么指导吗?

struct SecretDetailView: View {
  @State private var showDeleteAlert = false

  var table: some View {
    Table(selection: $selection, sortOrder: $sortOrder) {
        TableColumn("User Name", value: \.userName)
        ...
  } rows: {
        ForEach(secretItems) { secretItem in
            TableRow(secretItem)
                // Menue showing up with right click on table row for row manipulation
                .contextMenu {
                    Button("Delete Item") {
                        showDeleteAlert.toggle()
                    }
                    // alert not showing up here:
                    .alert(isPresented: $showDeleteAlert) {
                        Alert(
                            title: Text("Do you want to delete item?"),
                            message: Text(""),
                            primaryButton: .cancel(
                                Text("Cancel"),
                                action: { }
                            ),
                            secondaryButton: .destructive(
                                Text("Delete"),
                                action: {deleteSelectedSecretItem(secretItem) }
                            )
                        )
                    }
                }
        }

1 回复 | 直到 1 年前

Sweeper 1 年前

使用 alert 接受要呈现的值的重载,例如 alert(_:isPresented:presenting:actions:) 或 alert(item:content:) (在iOS 17中已弃用)。通过这种方式,您可以移动 警觉的 修改器位于 Table 相反

添加新的 @State 以存储要删除的项目,并在上下文菜单“删除”按钮的操作中设置此项。

// assuming secretItems is an array of "Item"
@State private var toBeDeletedItem: Item?

.contextMenu {
    Button("Delete Item") {
        showDeleteAlert.toggle()
        toBeDeletedItem = item
    }
}

// add this to the Table
.alert("Do you want to delete item?", isPresented: $showDeleteAlert, presenting: toBeDeletedItem) { item in
    Button("Delete", role: .destructive) {
        deleteSelectedSecretItem(item)
    }

    Button("Cancel", role: .cancel) { }
}

或者,如果您使用的是早期版本,并且 警报(_:呈现:呈现:操作:) 不可用:

.alert(item: $toBeDeletedItem) { item in
    Alert(
        title: Text("Do you want to delete item?"),
        message: Text(""),
        primaryButton: .cancel(
            Text("Cancel"),
            action: { }
        ),
        secondaryButton: .destructive(
            Text("Delete"),
            action: { deleteSelectedSecretItem(item) }
        )
    )
}
// You don't actually need showDeleteAlert!