我正在寻找一种方法来实现像 Mail.app 这样的三列布局的工具栏。此外，Notes.app 使用几乎相同的工具栏，两个应用程序之间唯一重要的区别是 Notes.app 看起来像WindowStyle is a HiddenTitleBarWindowStyle和 Mail.app 看起来像Default|TitleBarWindowStyle.
以下应该是正确的：
HiddenTitleBarWindowStyle)
DefaultWindowStyle with only a small Divider()-like line in the Toolbar.
哪个组合WindowStyle, WindowToolbarStyle and .toolbar我需要配置才能实现此设置吗？
我注意到无法删除 Notes.app 显示的分隔线。不过，我在文档中没有找到对任何此类元素的引用。
我已将问题简化为一个主要包含工具栏内容的简单应用程序。在我的原始代码中我使用两个嵌套NavigationViews，而在这个例子中我只使用了一个NavigationView有两个列表。但是，那Toolbar结果是一样的。
DefaultWindowStyle
import SwiftUI
@main
struct ToolbarTestApp: App {
var body: some Scene {
WindowGroup {
ContentView(titleBarIsHidden: true)
}
.windowToolbarStyle(UnifiedWindowToolbarStyle())
.commands {
SidebarCommands()
}
}
}
struct ContentView: View {
@State var destination: String = "Toolbar Test"
@State var detail: String = ""
var body: some View {
NavigationView {
List {
Button(action: {self.destination = "Item with the identifier: 1"}, label: {
Text("Item 1")
})
.buttonStyle(DefaultButtonStyle())
Button(action: {self.destination = "Item 2"}, label: {
Text("Item 2")
})
.buttonStyle(DefaultButtonStyle())
}
.listStyle(SidebarListStyle())
List {
NavigationLink(
destination: DetailView(text: "\(destination) – \(detail)").onAppear{self.detail = "Detail 1"},
label: {
Text("\(destination) – Detail 1")
})
NavigationLink(
destination: DetailView(text: "\(destination) – \(detail)").onAppear{self.detail = "Detail 2"},
label: {
Text("\(destination) – Detail 2")
})
}
.listStyle(InsetListStyle())
Text("\(destination) – \(detail)")
}
.navigationTitle(destination)
.navigationSubtitle(detail)
.toolbar(id: "nav") {
ToolbarItem(id: "plus", placement: ToolbarItemPlacement.principal, showsByDefault: true) {
HStack {
Button(action: {print("pressed")}, label: {
Image(systemName: "plus.circle")
})
}
}
ToolbarItem(id: "spacer", placement: ToolbarItemPlacement.confirmationAction, showsByDefault: true) {
HStack {
Spacer()
}
}
ToolbarItem(id: "sidebar.end", placement: ToolbarItemPlacement.confirmationAction, showsByDefault: true) {
Button(action: {print("pressed")}, label: {
Image(systemName: "sidebar.right")
})
}
}
}
}
这个例子将导致Toolbar永远不会显示分割整个整体的分割线Toolbar分为两部分。也是第一个ToolbarItem位于中心Toolbar。我尝试了所有ToolbarItemPlacement但都没有导致项目移动到标题附近的最左侧。
HiddenTitleBarWindowStyle
@main
struct ToolbarTestApp: App {
var body: some Scene {
WindowGroup {
ContentViewForHiddenTitleBar()
}
.windowStyle(HiddenTitleBarWindowStyle()) // added hidden title style
.windowToolbarStyle(UnifiedWindowToolbarStyle())
.commands {
SidebarCommands()
}
}
}
struct ContentViewForHiddenTitleBar: View {
@State var destination: String = "Toolbar Test"
@State var detail: String = ""
var body: some View {
NavigationView {
List {
Button(action: {self.destination = "Item with the identifier: 1"}, label: {
Text("Item 1")
})
.buttonStyle(DefaultButtonStyle())
Button(action: {self.destination = "Item 2"}, label: {
Text("Item 2")
})
.buttonStyle(DefaultButtonStyle())
}
.listStyle(SidebarListStyle())
// add geometry reader to trim title width in toolbar
GeometryReader { geometry in
List {
NavigationLink(
destination: DetailView(text: "\(destination) – \(detail)").onAppear{self.detail = "Detail 1"},
label: {
Text("\(destination) – Detail 1")
})
NavigationLink(
destination: DetailView(text: "\(destination) – \(detail)").onAppear{self.detail = "Detail 2"},
label: {
Text("\(destination) – Detail 2")
})
}
// there is no title anymore so let's fake it.
.toolbar(id: "list navigation") {
ToolbarItem(id: "title", placement: ToolbarItemPlacement.navigation, showsByDefault: true) {
VStack(alignment: .leading) {
Text(destination)
.font(.headline)
.frame(maxWidth: .infinity, alignment: .leading)
Text(detail)
.font(.subheadline)
.opacity(0.6)
.frame(maxWidth: .infinity, alignment: .leading)
}
.frame(width: geometry.size.width)
}
}
}
.listStyle(InsetListStyle())
Text("\(destination) – \(detail)")
}
.navigationTitle(destination)
.navigationSubtitle(detail)
.toolbar(id: "nav") {
// primary action will place the item next to the divider line.
ToolbarItem(id: "plus", placement: ToolbarItemPlacement.primaryAction, showsByDefault: true) {
HStack {
Button(action: {print("pressed")}, label: {
Image(systemName: "plus.circle")
})
}
}
ToolbarItem(id: "spacer", placement: ToolbarItemPlacement.confirmationAction, showsByDefault: true) {
HStack {
Spacer()
}
}
ToolbarItem(id: "sidebar.end", placement: ToolbarItemPlacement.confirmationAction, showsByDefault: true) {
Button(action: {print("pressed")}, label: {
Image(systemName: "sidebar.right")
})
}
}
}
}
这个例子将导致Toolbar将始终显示全高分隔线。即使标题太长。因此一个GeometryReader加入。这很好，直到侧边栏折叠为止。的放置ToolbarItems不会是正确的。另外在定制时Toolbar有可能删除标题，但这应该是不可能的。
默认标题栏样式很好，您只需将工具栏项附加到顶部 NavigationView 的子视图，例如：
var body: some View {
NavigationView {
List {
...
}
.listStyle(SidebarListStyle())
.toolbar {
ToolbarItem {
Button(action: { }, label: {
Image(systemName: "sidebar.right")
})
}
}
List {
...
}
.listStyle(InsetListStyle())
.toolbar {
ToolbarItem {
Button(action: { }, label: {
Image(systemName: "plus.circle")
})
}
}
Text("\(destination) – \(detail)")
}
.navigationTitle(destination)
.navigationSubtitle(detail)
}
我没有将任何工具栏项附加到第三列（Text）但您可以 - 只需确保将相同的工具栏项目附加到您的 DetailViews，因为当用户导航时，其工具栏将替换文本的工具栏。 （如果您不确定我的意思，请尝试一下，您很快就会明白我在说什么:)