Lesson 3: Enable the Edit Appointment Form

• Dec 17, 2020
• 2 minutes to read

Edit Appointment Page allows users to schedule new events or edit existing appointments. You can specify a gesture (for example, tap or double tap) that invokes this form.

Open the solution created in Lesson 2 and perform the following steps to set up the scheduler so that is shows the Edit Appointment form when a user taps an appointment or empty cell within the work week view.

1. Subscribe to the view’s Tap event.

   XAML

   <dxsch:WorkWeekView Start="{Binding StartDate}"
                       FirstDayOfWeek="Monday"
                       WorkDays="Monday,Tuesday,Wednesday,Friday" 
                       WorkTime="7:00:00-19:00:00"
                       ShowWorkTimeOnly="True"
                       TimeScaleInterval="01:00:00"
                       TimeScaleSlotCount="4"
                       SnapToCellsMode="Never"
                       Tap="WorkWeekView_Tap">
       <dxsch:WorkWeekView.DataStorage>
           <dxsch:SchedulerDataStorage x:Name="storage">
               <!-- ... -->
           </dxsch:SchedulerDataStorage>
       </dxsch:WorkWeekView.DataStorage>
   </dxsch:WorkWeekView>
   

2. In the event handler:

   1. Create an AppointmentEditPage instance. Use one of the following constructors:

      • AppointmentEditPage(DateTime, DateTime, Boolean, SchedulerDataStorage, Boolean) - accepts the scheduler storage and an initial time interval if you create a new appointment.
      • AppointmentEditPage(AppointmentItem, SchedulerDataStorage, Boolean) - accepts the scheduler storage and an appointment if you edit an existing appointment.

   2. Call the Navigation.PushAsync method and pass the created page as a parameter.

      C#

      using Xamarin.Forms;
      using DevExpress.XamarinForms.Scheduler;
      
      namespace Scheduler_GettingStarted {
          public partial class MainPage : ContentPage {
              public MainPage() {
                  InitializeComponent();
              }
      
              private void WorkWeekView_Tap(object sender, SchedulerGestureEventArgs e) {
                  if (e.AppointmentInfo == null) {
                      ShowNewAppointmentEditPage(e.IntervalInfo);
                      return;
                  }
                  AppointmentItem appointment = e.AppointmentInfo.Appointment;
                  ShowAppointmentEditPage(appointment);
              }
      
              private void ShowAppointmentEditPage(AppointmentItem appointment) {
                  AppointmentEditPage appEditPage = new AppointmentEditPage(appointment, this.storage);
                  Navigation.PushAsync(appEditPage);
              }
      
              private void ShowNewAppointmentEditPage(IntervalInfo info) {
                  AppointmentEditPage appEditPage = new AppointmentEditPage(info.Start, info.End, 
                                                                           info.AllDay, this.storage);
                  Navigation.PushAsync(appEditPage);
              }
          }
      }
      

      Note

      The SchedulerGestureEventArgs.AppointmentInfo.Appointment returns an appointment that has a visual representation (an appointment with Type set to Normal, Occurrence, ChangedOccurrence, DeletedOccurrence). To edit all occurrences in a recurrence chain, use the GetPattern method to obtain the occurrence’s pattern.

3. In the App.xaml.cs file, assign a NavigationPage instance to the Application.MainPage property and add the MainPage content page to the navigation stack (the application’s root page):

   C#

   namespace Scheduler_GettingStarted {
       public partial class App : Application {
           public App() {
               InitializeComponent();
   
               // MainPage = new MainPage();
               MainPage = new NavigationPage(new MainPage());
           }
   
           // ...
       }
   }
   

The scheduler now displays the Edit Appointment form when a user taps an appointment or empty cell within the work week view.

The next lesson explains how to specify custom labels for appointments.