SchedulerControl.AllowAppointmentConflicts Event

Occurs when the scheduler finds appointments that are in conflict, and the OptionsCustomization.AllowAppointmentConflicts property is set to Custom.

Namespace: DevExpress.Xpf.Scheduler

Assembly: DevExpress.Xpf.Scheduler.v19.1.dll

Declaration

C#

public event AppointmentConflictEventHandler AllowAppointmentConflicts

VB.NET

Public Event AllowAppointmentConflicts As AppointmentConflictEventHandler

Event Data

The AllowAppointmentConflicts event's data class is AppointmentConflictEventArgs. The following properties provide information specific to this event:

Property	Description
Appointment	Gets the appointment for which the event was raised. Inherited from AppointmentEventArgs.
AppointmentClone	Gets the clone of the appointment being processed in the SchedulerControl.AllowAppointmentConflicts or the SchedulerControl.AllowAppointmentConflicts events.
Conflicts	Gets the collection of appointments which are considered to be conflicting with the current appointment.
Interval	Gets the time interval which the event was raised for.

The event data class exposes the following methods:

Method	Description
RemoveConflictsWithDifferentResource(AppointmentBaseCollection, Object)	Removes all the conflicting appointments from the specified collection whose Appointment.ResourceId doesn’t match the specified Id.

Remarks

Important

You are viewing documentation for the legacy WPF Scheduler control. If you’re starting a new project, we strongly recommend that you use a new control declared in the DevExpress.Xpf.Scheduling namespace. If you decide to upgrade an existing project in order to switch to the updated scheduler control, see the Migration Guidelines document.

Handle the AllowAppointmentConflicts event to manually decide whether the current appointment conflicts with any other appointments. The appointment’s copy to be checked can be accessed via the AppointmentEventArgs.Appointment property.

Note

The AllowAppointmentConflicts event is fired only if the OptionsCustomization.AllowAppointmentConflicts property is set to AppointmentConflictsMode.Custom.

This event’s arguments provide the AppointmentConflictEventArgs.Conflicts property, which returns the collection of appointments that are considered to be conflicting by the SchedulerControl. All these appointments conflict with the current appointment, since their time intervals intersect and they are assigned the same resource. If the Conflicts collection is empty, this means that there are no conflicting appointments.

The AppointmentConflictEventArgs.AppointmentClone property contains an appointment modified due to an end-user’s action. This is the appointment that intersects with existing ones. The Appointment property provides access to the current appointment before modification. So, when an appointment is dragged, its clone may conflict with original appointment, and the Conflicts collection may contain one element - the original appointment.

Note

If you determine that the current appointment has no conflicts, you should clear the Conflicts collection in this event’s handler. If you determine that the current appointment has at least one conflict, then the Conflicts collection should contain at least one object that is different from the current appointment. The non-empty Conflicts collection cancels the user’s action that caused a conflict. The common practice is to clear the Conflicts collection at the beginning, and populate it with any appointment if the user’s action should be canceled. You can even create a fake appointment for this purpose and add it to the collection.

Note

The source appointment (accessed via the AppointmentEventArgs.Appointment property) or its copy isn’t considered to be conflicting if it’s present in the Conflicts collection. There should be other appointments in this collection, to indicate the conflict.

Example

This example demonstrates how to prevent end-users from having appointments within a certain time interval (from 2 PM to 3 PM). To implement end-user restrictions, handle the SchedulerControl.AllowAppointmentCreate event to prevent end-users from creating appointments within a certain time interval and the SchedulerControl.AllowAppointmentConflicts event to prevent an existing appointment from being dragged to the same time interval:

Note

A complete sample project is available at https://github.com/DevExpress-Examples/how-to-set-end-user-restrictions-e2516.

MainWindow.xaml (C#)

<Window x:Class="WpfApplication1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:dxsch="http://schemas.devexpress.com/winfx/2008/xaml/scheduler"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <dxsch:SchedulerControl Name="schedulerControl1"
                                HorizontalAlignment="Stretch" VerticalAlignment="Stretch"                               
                                AllowAppointmentConflicts="schedulerControl1_AllowAppointmentConflicts" 
                                AllowAppointmentCreate="schedulerControl1_AllowAppointmentCreate">
            <dxsch:SchedulerControl.DayView>
                <dxsch:DayView DayCount="3" />
            </dxsch:SchedulerControl.DayView>
            <dxsch:SchedulerControl.OptionsCustomization>
                <dxsch:OptionsCustomization AllowAppointmentConflicts="Custom" AllowAppointmentCreate="Custom" />
            </dxsch:SchedulerControl.OptionsCustomization>
        </dxsch:SchedulerControl>
    </Grid>
</Window>

MainWindow.xaml.cs

using System;
using System.Windows;
using DevExpress.XtraScheduler;
using DevExpress.Xpf.Scheduler;

namespace WpfApplication1 {
    public partial class MainWindow : Window {
        public MainWindow() {
            InitializeComponent();
        }
        TimeOfDayInterval restrictedArea = 
            new TimeOfDayInterval(TimeSpan.FromHours(14), TimeSpan.FromHours(15));

        private void schedulerControl1_AllowAppointmentConflicts(object sender,
            AppointmentConflictEventArgs e) {
            TimeInterval interval = e.Interval;
            if (!IsIntervalAllowed(interval))
                e.Conflicts.Add(e.AppointmentClone);
        }

        private void schedulerControl1_AllowAppointmentCreate(object sender, 
            AppointmentOperationEventArgs e) {
            e.Allow = IsIntervalAllowed(schedulerControl1.ActiveView.SelectedInterval);
        }

        private bool IsIntervalAllowed(TimeInterval interval) {
            DateTime dayStart = interval.Start.Date;
            while (dayStart < interval.End) {
                if (!IsIntervalAllowed(interval, dayStart))
                    return false;
                dayStart = dayStart.AddDays(1);
            }
            return true;
        }

        bool IsIntervalAllowed(TimeInterval interval, DateTime dayStart) {
            TimeInterval lunchTime = new TimeInterval(dayStart.Add(restrictedArea.Start), 
                dayStart.Add(restrictedArea.End));
            return !interval.IntersectsWithExcludingBounds(lunchTime);
        }        
    }
}

MainWindow.xaml (VB.NET)

<Window x:Class="WpfApplication1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:dxsch="http://schemas.devexpress.com/winfx/2008/xaml/scheduler"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <dxsch:SchedulerControl Name="schedulerControl1"
                                HorizontalAlignment="Stretch" VerticalAlignment="Stretch"                               
                                AllowAppointmentConflicts="schedulerControl1_AllowAppointmentConflicts" 
                                AllowAppointmentCreate="schedulerControl1_AllowAppointmentCreate">
            <dxsch:SchedulerControl.DayView>
                <dxsch:DayView DayCount="3" />
            </dxsch:SchedulerControl.DayView>
            <dxsch:SchedulerControl.OptionsCustomization>
                <dxsch:OptionsCustomization AllowAppointmentConflicts="Custom" AllowAppointmentCreate="Custom" />
            </dxsch:SchedulerControl.OptionsCustomization>
        </dxsch:SchedulerControl>
    </Grid>
</Window>

MainWindow.xaml.vb

Imports Microsoft.VisualBasic
Imports System
Imports System.Windows
Imports DevExpress.XtraScheduler
Imports DevExpress.Xpf.Scheduler

Namespace WpfApplication1
    Partial Public Class MainWindow
        Inherits Window
        Public Sub New()
            InitializeComponent()
        End Sub
        Private restrictedArea As New TimeOfDayInterval(TimeSpan.FromHours(14), TimeSpan.FromHours(15))

        Private Sub schedulerControl1_AllowAppointmentConflicts(ByVal sender As Object, _
                                                          ByVal e As AppointmentConflictEventArgs)
            Dim interval As TimeInterval = e.Interval
            If (Not IsIntervalAllowed(interval)) Then
                e.Conflicts.Add(e.AppointmentClone)
            End If
        End Sub

        Private Sub schedulerControl1_AllowAppointmentCreate(ByVal sender As Object, _
                                                             ByVal e As AppointmentOperationEventArgs)
            e.Allow = IsIntervalAllowed(schedulerControl1.ActiveView.SelectedInterval)
        End Sub

        Private Function IsIntervalAllowed(ByVal interval As TimeInterval) As Boolean
            Dim dayStart As DateTime = interval.Start.Date
            Do While dayStart < interval.End
                If (Not IsIntervalAllowed(interval, dayStart)) Then
                    Return False
                End If
                dayStart = dayStart.AddDays(1)
            Loop
            Return True
        End Function

        Private Function IsIntervalAllowed(ByVal interval As TimeInterval, _
                                           ByVal dayStart As DateTime) As Boolean
            Dim lunchTime As New TimeInterval(dayStart.Add(restrictedArea.Start), _
                                              dayStart.Add(restrictedArea.End))
            Return Not interval.IntersectsWithExcludingBounds(lunchTime)
        End Function
    End Class
End Namespace

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the AllowAppointmentConflicts event.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

how-to-set-end-user-restrictions-e2516/CS/WpfApplication1/MainWindow.xaml#L9

HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
AllowAppointmentConflicts="schedulerControl1_AllowAppointmentConflicts"
AllowAppointmentCreate="schedulerControl1_AllowAppointmentCreate">

wpf-schedulercontrol-api-t442105/CS/SchedulerControl_WPF_API/CodeExamples/AppointmentConflicts.cs#L11

scheduler.OptionsCustomization.AllowAppointmentConflicts = AppointmentConflictsMode.Custom;
 scheduler.AllowAppointmentConflicts += Scheduler_AllowAppointmentConflicts;

VB.NET

wpf-schedulercontrol-api-t442105/VB/SchedulerControl_WPF_API/CodeExamples/AppointmentConflicts.vb#L10

scheduler.OptionsCustomization.AllowAppointmentConflicts = AppointmentConflictsMode.Custom
 AddHandler scheduler.AllowAppointmentConflicts, AddressOf Scheduler_AllowAppointmentConflicts