如何从一个孩子扩展到其第一个父母? [英] How to expand from a child to its very first parent?
问题描述
我正在尝试从根(父级的父级....)开始扩展所有子级，直到真正的节点为止.如何在不单击每个节点的情况下做到这一点?
I'm trying to expand all children starting on root(parent of a parent....) until the actual node. How can I do it without clicking on every node?
我正在使用它来显示目录内容，并且我想显示用户在关闭/打开应用程序之前的最后路径.
I'm using it to show directories content and I would like to show the last path the user was before closing/opening the app.
第一张图片显示了我想要的样子，第二张图片显示了当前显示的内容.
The first picture shows how I would like it to be and the second picture shows what is shown at the moment.
代码未完成.有很多测试和调试.
The code is not done. There is a lot of testing and debugging.
我在此问题中添加了所有相关代码.
I added all relevant code to this questions.
到目前为止，我的应用程序读取目录，并且如果此目录上有任何mp3文件，它将显示在表格视图中，但这不是我的问题的一部分，而只是背景.
So far my app reads directories and if there is any mp3 file on this directory it is shown on a table view, but it is not part of my question, just a background.
extension ViewController: NSOutlineViewDataSource {
func outlineView(_ outlineView: NSOutlineView, numberOfChildrenOfItem item: Any?) -> Int {
let directoryItem = item as? DirectoryItem ?? rootItem
return directoryItem.childItems.count
}
func outlineView(_ outlineView: NSOutlineView, child index: Int, ofItem item: Any?) -> Any {
let directoryItem = item as? DirectoryItem ?? rootItem
return directoryItem.childItems[index]
}
func outlineView(_ outlineView: NSOutlineView, isItemExpandable item: Any) -> Bool {
let directoryItem = item as? DirectoryItem ?? rootItem
return directoryItem.isExpandable
}
}
extension ViewController: NSOutlineViewDelegate {
func outlineViewSelectionDidChange(_ notification: Notification) {
singleClick()
}
func outlineView(_ outlineView: NSOutlineView, shouldExpandItem item: Any) -> Bool {
let directoryItem = item as? DirectoryItem ?? rootItem
return (directoryItem.childItems.count != 0)
}
func outlineView(_ outlineView: NSOutlineView, shouldShowOutlineCellForItem item: Any) -> Bool {
let directoryItem = item as? DirectoryItem ?? rootItem
return (directoryItem.childItems.count != 0)
}
func outlineView(_ outlineView: NSOutlineView, viewFor tableColumn: NSTableColumn?, item: Any) -> NSView? {
var text = ""
if let directories = item as? DirectoryItem {
if(directories.isdir) {
text = directories.name
let tableCell = outlineView.makeView(withIdentifier: NSUserInterfaceItemIdentifier(rawValue: "cell"), owner: self) as! NSTableCellView
tableCell.textField!.stringValue = text
return tableCell
}
}
return nil
}
}
@objc func singleClick()
{
if let item = self.outlineView.item(atRow: self.outlineView.selectedRow) {
self.arrMp3File.removeAll()
do {
let xx = (item as! DirectoryItem).url
let b = self.getSubDir(path: xx.path)
self.saveDefaults(url: xx)
DispatchQueue.global(qos: .background).async { [weak self] in
DispatchQueue.main.async {
self?.progressIndicator.isHidden = false
self?.progressIndicator.startAnimation(self)
}
for bb in b {
self?.getTagsFromFile(file: xx.path+"/"+bb)
}
DispatchQueue.main.async {
self?.arrMp3File.sort(by: {
$0.file < $1.file
})
self?.tableView.reloadData()
self?.loadTagsFromButton.isEnabled = true
self?.progressIndicator.stopAnimation(self)
self?.progressIndicator.isHidden = true
}
}
}
}
}
override func viewDidLoad() {
super.viewDidLoad()
let defaults = UserDefaults.standard
let lastDirectory = defaults.url(forKey: "LastDirectory")
print(lastDirectory ?? "")
// rootItem = DirectoryItem(url: lastDirectory ?? FileManager.default.homeDirectoryForCurrentUser)
// getDir(path: age)
outlineView.dataSource = self
outlineView.delegate = self
tableView.delegate = self
tableView.dataSource = self
tableView.doubleAction = #selector(doubleClickOnResultRow)
// outlineView.action = #selector(singleClick)
self.progressIndicator.isHidden = true
self.tableView.reloadData()
}
class Directories {
var name: String
var subDirectories: [String]
init(name: String, subDirectories: [String]) {
self.name = name
self.subDirectories = subDirectories
}
}
class DirectoryItem {
var name: String
var url: URL
var isdir: Bool
var prev: URL
lazy var isExpandable: Bool = {
do {
return try url.resourceValues(forKeys: [.isDirectoryKey]).isDirectory ?? false
} catch let error as NSError {
return false
}
}()
lazy var childItems: [DirectoryItem] = {
do {
let urls = try FileManager.default.contentsOfDirectory(at: url,
includingPropertiesForKeys: [.isDirectoryKey],
options: [.skipsHiddenFiles])
var aa: [DirectoryItem]
var bb: [DirectoryItem]
bb = []
aa = urls.map { DirectoryItem(url: $0) }
for a in aa {
if(a.isdir) {
bb.append(a)
// print(a)
}
}
return bb
//return urls.map { DirectoryItem(url: $0) }
} catch let error as NSError {
return []
}
}()
init(url: URL) {
self.url = url
self.name = url.lastPathComponent
self.isdir = url.hasDirectoryPath
self.prev = url.deletingLastPathComponent()
}
}
推荐答案
如果您保存了用户上次访问的URL，则可以通过三个步骤显示并选择它:
If you have saved the URL that the user was last visiting, then you can show and select it in three steps:
-
将URL转换为表示URL路径组成部分的
DirectoryItem数组.
询问大纲视图以展开每个项目，从作为根节点直接子项的项目开始.
Ask the outline view to expand each of those items, starting with the item that is a direct child of the root node.
询问大纲视图以选择最后一项.
Ask the outline view to select the last item.
未经测试的代码:
func reveal(_ url: URL) {
// Step 1.
let items = itemHierarchy(for: url)
// Step 2.
for item in items {
outlineView.expandItem(item)
}
// Step 3.
if
let last = items.last,
case let row = outlineView.row(forItem: last),
row != -1
{
let set = IndexSet(integer: row)
outlineView.selectRowIndexes(set, byExtendingSelection: false)
}
}
private func itemHierarchy(for url: URL) -> [DirectoryItem] {
var items: [DirectoryItem] = []
var current: DirectoryItem = rootItem
for component in url.pathComponents {
guard let child = current.childItems.first(where: { $0.name == component }) else {
return items
}
items.append(child)
current = child
}
return items
}
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