title: Change the value of an object inside an Observable of sequence using RxSwift
body: <p>I have an observable sequence which represent my displayed sessions as follow : </p>
  
  
  
  <pre class="lang-swift prettyprint-override"><code> private let displayedSessions =
   PublishSubject&lt;[ProgramDaySessionsModels.ViewModels.Session]&gt;()
  </code></pre>
  
  <p>And here is my ViewModel:</p>
  
  <pre class="lang-swift prettyprint-override"><code>struct ViewModels {
  
          struct Session{
              let id : Int?
              let title : String?
              let location : String?
              var isAddedToCalendar : Bool?
              var isAddedToFavorite : Bool?
              let time : String?
          }
      }
  </code></pre>
  
  <p>The displayed sessions is being binded to a table view:</p>
  
  <pre class="lang-swift prettyprint-override"><code>func setupCellBinding(){
      displayedSessions
          .asObservable()
          .bind(to:
              tableView
                  .rx
                  .items(cellIdentifier:
                      R.reuseIdentifier.programDaySessionCell.identifier,
                         cellType: ProgramDaySessionCell.self)
          ){
              ( row, element, cell ) in
  
              cell.setup(withViewModel: element)
          }
          .disposed(by: disposeBag)
  }
  </code></pre>
  
  <p>Now after i call the setup method in the cell, i want to subscribe to an image tap inside my cell, regardless what is the subscription logic will be ....</p>
  
  <p>I want after that to update my displayed viewModel , for example i want to change the property <code>isAddedToCalendar</code> to false/true when the subscription logic end... </p>
  
  <p><strong>My question is , How to update or change a value stored in the <code>Subject</code> <em>without calling</em> <code>onNext</code> operator</strong></p>