目标
我想从列表中 ForEach
上的 SectionedFetchRequest
中删除一个项目。我发现的唯一解决方案是常规 FetchRequest
我已设法将其从 UIList 中删除,但没有从 CoreData 的 ViewContext
中删除。
我的问题很独特,因为我试图从不同于 FetchRequest 的 SectionedFetchRequest 中删除
@SectionedFetchRequest(entity: Todo.entity(), sectionIdentifier: \.dueDateRelative, sortDescriptors: [NSSortDescriptor(keyPath: \Todo.dueDate, ascending: true)], predicate: nil, animation: Animation.linear)
var sections: SectionedFetchResults<String, Todo>
var body: some View {
NavigationView {
List {
ForEach(sections) { section in
Section(header: Text(section.id.description)) {
ForEach(section) { todo in
TodoRowView(todo: todo)
.frame(maxWidth: .infinity)
.listRowSeparator(.hidden)
}
.onDelete { row in
deleteTodo(section: section.id.description, row: row)
}
}
}
}
func deleteTodo(section: String, row: IndexSet) {
// Need to delete from list and CoreData viewContex.
}
// My old way of deleting notes with a regular fetch Request
func deleteNote(at offsets: IndexSet) {
for index in offsets {
let todo = todos[index]
viewContext.delete(todo)
}
try? viewContext.save()
}
最佳答案
这就是您使用链接的方式...
将此添加到 TodoRowView(todo: todo)
.swipeActions(content: {
Button(role: .destructive, action: {
deleteTodo(todo: todo)
}, label: {
Image(systemName: "trash")
})
})
而你需要在View
public func deleteTodo(todo: Todo){
viewContext.delete(todo)
do{
try viewContext.save()
} catch{
print(error)
}
}
或者您可以使用当前设置,该设置在 ForEach
onDelete
.onDelete { indexSet in
deleteTodo(section: Array(section), offsets: indexSet)
}
使用这种方法
func deleteTodo(section: [Todo], offsets: IndexSet) {
for index in offsets {
let todo = section[index]
viewContext.delete(todo)
}
try? viewContext.save()
}
当然,要让其中任何一个工作,你需要一个工作
@Environment(\.managedObjectContext) var viewContext
在文件的顶部
关于ios - 从带有部分的 SwiftUI 列表中删除 CoreData,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/70399514/