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过滤域时显示NSPROGRESS指示器

realm swift

Jay · 技术社区 · 8 年前

安装程序

Swift 3应用程序RealmSwift 2.10.1,带有一个按钮、tableview和一个不确定的旋转进度指示器(旋转圆圈)

当用户单击按钮时,查询一个大型领域数据库(数百万条记录),在等待结果的同时,显示进度指示器。

过滤完成后,进度指示器才会显示。

//called from button click
func performFilterAction() {  
     self.filterProgressIndicator.isHidden = false
     self.filterProgressIndicator.startAnimation(nil)
     let predicate = NSPredicate(format: "location = %@", "US")
     let realm = try! Realm()
     self.results = realm.objects(MyClass.self).filter(predicate)
     self.tableView.reloadData()
     self.filterProgressIndicator.isHidden = true
}

另外 :

另一个问题是,即使进度指示器隐藏在代码末尾,它也不会隐藏在UI中。

func performFilterAction() {
     self.filterProgressIndicator.isHidden = false
     self.filterProgressIndicator.startAnimation(nil)

     DispatchQueue.global(qos: .background).async {  
          let predicate = NSPredicate(format: "location = %@", "US")
          let realm = try! Realm()
          self.results = realm.objects(MyClass.self).filter(predicate)
          DispatchQueue.main.async {
              self.tableView.reloadData()
              self.filterProgressIndicator.isHidden = true
          }
     }
}

此应用程序正在后台修改autolayout引擎从主线程访问引擎后的线程。这个可以

另一次尝试:

根据提供的答案,我实现了如下收集通知

func performFilterAction1() {
    self.filterProgressIndicator.isHidden = false
    self.filterProgressIndicator.startAnimation(nil)
    let predicate = NSPredicate(format: "location = %@", "US")
    let realm = try! Realm()
    self.results = realm.objects(MyClass.self).filter(predicate)

    self.notificationToken = self.results.addNotificationBlock { [weak self] (changes: RealmCollectionChange) in
        guard let tableView = self?.filterTableView else { return }
        switch changes {
        case .initial:
            // Results are now populated and can be accessed without blocking the UI
            tableView.reloadData()
            self?.filterProgressIndicator.isHidden = true
            break
        case .update(_, let deletions, let insertions, let modifications):
            break
        case .error(let error):
            // An error occurred while opening the Realm file on the background worker thread
            fatalError("\(error)")
            break
        }
    }
}

其结果是:进度指示器直到之后过滤器完成后,它只是瞬间“闪烁”。

772.00 ms   58.7%   0 s      Main Thread  0x72995
742.00 ms   56.5%   0 s       start
742.00 ms   56.5%   0 s        main
742.00 ms   56.5%   0 s         NSApplicationMain
625.00 ms   47.6%   1.00 ms          -[NSApplication run]
377.00 ms   28.7%   0 s           -[NSApplication(NSEvent) sendEvent:]
342.00 ms   26.0%   0 s            -[NSWindow(NSEventRouting) sendEvent:]
342.00 ms   26.0%   0 s             -[NSWindow(NSEventRouting) _reallySendEvent:isDelayedEvent:]
342.00 ms   26.0%   0 s              -[NSWindow(NSEventRouting) _handleMouseDownEvent:isDelayedEvent:]
331.00 ms   25.2%   0 s               -[NSControl mouseDown:]
330.00 ms   25.1%   0 s                -[NSButtonCell trackMouse:inRect:ofView:untilMouseUp:]
330.00 ms   25.1%   0 s                 -[NSCell trackMouse:inRect:ofView:untilMouseUp:]
319.00 ms   24.2%   0 s                  _os_activity_initiate_impl
319.00 ms   24.2%   0 s                   -[NSButtonCell _sendActionFrom:]
319.00 ms   24.2%   0 s                    -[NSCell _sendActionFrom:]
319.00 ms   24.2%   0 s                     _os_activity_initiate_impl
319.00 ms   24.2%   0 s                      __26-[NSCell _sendActionFrom:]_block_invoke
319.00 ms   24.2%   0 s                       -[NSControl sendAction:to:]
319.00 ms   24.2%   0 s                        -[NSApplication(NSResponder) sendAction:to:from:]
318.00 ms   24.2%   0 s                         _os_activity_initiate_impl
259.00 ms   19.7%   0 s                          @objc FilterVC.filterAction(Any) -> ()
259.00 ms   19.7%   0 s                           FilterVC.filterAction(Any) -> ()
257.00 ms   19.5%   0 s                            FilterVC.test() -> ()
238.00 ms   18.1%   0 s                             Results.count.getter
238.00 ms   18.1%   0 s                              -[RLMResults count]
238.00 ms   18.1%   0 s                               -[RLMResults count]::$_1::operator()() const
238.00 ms   18.1%   0 s                                realm::Results::size()
238.00 ms   18.1%   0 s                                 realm::Query::count(unsigned long, unsigned long, unsigned long) const
238.00 ms   18.1%   0 s                                  realm::Query::aggregate_internal(realm::Action, realm::DataType, bool, realm::ParentNode*, realm::QueryStateBase*, unsigned long, unsigned long, realm::SequentialGetterBase*) const

2 回复 | 直到 8 年前

bdash 8 年前

这是一个完美的用例 Realm's collection notifications

var notificationToken: NotificationToken? = nil
var results: Results<MyClass>? = nil

func performFilterAction() {
  filterProgressIndicator.isHidden = false
  filterProgressIndicator.startAnimation(nil)

  let realm = try! Realm()
  results = realm.objects(MyClass.self).filter("location = %@", "US")
  notificationToken = results.addNotificationBlock { [weak self] (changes: RealmCollectionChange) in
    guard let tableView = self?.tableView else { return }
    switch changes {
    case .initial:
      // Results are now populated and can be accessed without blocking the UI
      tableView.reloadData()
      self.filterProgressIndicator.isHidden = true
      break
    case .update(_, let deletions, let insertions, let modifications):
      // Query results have changed, so apply them to the UITableView
      tableView.beginUpdates()
      tableView.insertRows(at: insertions.map({ IndexPath(row: $0, section: 0) }),
                         with: .automatic)
      tableView.deleteRows(at: deletions.map({ IndexPath(row: $0, section: 0)}),
                         with: .automatic)
      tableView.reloadRows(at: modifications.map({ IndexPath(row: $0, section: 0) }),
                         with: .automatic)
      tableView.endUpdates()
      break
    case .error(let error):
      // An error occurred while opening the Realm file on the background worker thread
      fatalError("\(error)")
      break
    }
  }
}

deinit {
  notificationToken?.stop()
}

这使您可以在执行初始过滤时显示进度指示器,并在对集合中的数据进行更改时提供动画更新。如果你不在乎后者,你可以打电话 reloadData() .update 案例也是如此。

Alain T. 8 年前

你有什么视觉上的东西是在自我时触发的吗。结果发生了变化(例如在didSet中)?如果你这样做了,那么这可能就是导致第二个解决方案出错的原因。

您可以将加载过程发送到主线程,而不是后台线程(即第一种和第二种方法的混合),以便进度指示器有机会出现:

func performFilterAction() {
     self.filterProgressIndicator.isHidden = false
     self.filterProgressIndicator.startAnimation(nil)

     DispatchQueue.main.async {  
          let predicate = NSPredicate(format: "location = %@", "US")
          let realm = try! Realm()
          self.results = realm.objects(MyClass.self).filter(predicate)
          self.tableView.reloadData()
          self.filterProgressIndicator.isHidden = true
     }
}

func performFilterAction() {
     self.filterProgressIndicator.isHidden = false
     self.filterProgressIndicator.startAnimation(nil)

     DispatchQueue.global(qos: .background).async {  
          let predicate = NSPredicate(format: "location = %@", "US")
          let realm = try! Realm()
          let newResults = realm.objects(MyClass.self).filter(predicate)
          DispatchQueue.main.async {
              self.results = newResults
              self.tableView.reloadData()
              self.filterProgressIndicator.isHidden = true
          }
     }
}