17 Using a Calendar Component

17.1.1 Calendar Use Cases and Examples

The calendar component provides the features you need to implement calendar-related functions such as creating activities in daily, weekly, monthly or list view. It features a customizable toolbar that can be used for switching views. It has configurable start of the week and start of the day functions. Like other ADF Faces components, it supports skinning in order to customize its style and appearance.

You can create popups by inserting them into the calendar facets to add more functionality. You can also implement the calendar so the user can drag and drop activities from one area to another within the calendar.

The calendar uses the CalendarModel class to display the activities for a given time period. You must create your own implementation of the model class for your calendar. If your application uses the Fusion technology stack, then you can create ADF Business Components over your data source that represents the activities, and the model will be created for you. You can then declaratively create the calendar, and it will automatically be bound to that model. For more information, see the "Using the ADF Faces Calendar Component" section of the Oracle Fusion Middleware Fusion Developer's Guide for Oracle Application Development Framework.

If your application does not use the Fusion technology stack, then you create your own implementation of the CalendarModel class and the associated CalendarActivity and CalendarProvider classes. The classes are abstract classes with abstract methods. You must provide the functionality behind the methods, suitable for your implementation of the calendar. For more information, see Section 17.2, "Creating the Calendar."

17.1.2 Additional Functionality for the Calendar

You may find it helpful to understand other ADF Faces features before you implement your calendar component. Additionally, once you have added a calendar component to your page, you may find that you need to add functionality such as validation and accessibility. Following are links to other functionality that calendar components can use.

• Client components: Components can be client components. To work with the components on the client, see Chapter 4, "Using ADF Faces Client-Side Architecture."

• JavaScript APIs: All components have JavaScript client APIs that you can use to set or get property values. For more information, see the ADF Faces JavaScript API documentation.

• Events: Components fire both server-side and client-side events that you can have your application react to by executing some logic. For more information, see Chapter 6, "Handling Events."

• You can display tips and messages, as well as associate online help with calendar component. For more information, see Chapter 19, "Displaying Tips, Messages, and Help."

• You may want other components on the page to update based on selections you make from a calendar component. For more information, see Section 5.3, "Using the Optimized Lifecycle."

• You can change the appearance using skins. For more information, see Chapter 28, "Customizing the Appearance Using Styles and Skins."

• You can make your components accessible. For more information, see Chapter 30, "Developing Accessible ADF Faces Pages."

• Instead of entering values for attributes that take strings as values, you can use property files. These files allow you to manage translation of these strings. For more information, see Chapter 29, "Internationalizing and Localizing Pages."

• You can create popups for additional functionality. For more information about using these events to provide additional functionality, see Section 17.4, "Adding Functionality Using Popup Components."

• If your application uses the Fusion technology stack, then you can create calendars based on how your ADF Business components are configured. For more information, see the "Creating a Basic Databound Page" chapter of the Oracle Fusion Middleware Fusion Developer's Guide for Oracle Application Development Framework. If your application uses Enterprise JavaBeans, you can do the same. For more information, see the “Creating a Basic Databound Page" of the Oracle Fusion Middleware Java EE Developer's Guide for Oracle Application Development Framework.

17.2.1 Calendar Classes

The calendar component must be bound to an implementation of the CalendarModel class. The CalendarModel class contains the data for the calendar. This class is responsible for returning a collection of calendar activities, given the following set of parameters:

• Provider ID: The owner of the activities. For example, you may implement the CalendarModel class such that the calendar can return just the activities associated with the owner currently in session, or it can also return other owners' activities.

• Time range: The expanse of time for which all activities that begin within that time should be returned. A date range for a calendar is inclusive for the start time and exclusive for the end time (also known as half-open), meaning that it will return all activities that intersect that range, including those that start before the start time, but end after the start time (and before the end time).

A calendar activity represents an object on the calendar, and usually spans a certain period of time. The CalendarActivity class is an abstract class whose methods you can implement to return information about the specific activities.

Activities can be recurring, have associated reminders, and be of a specific time type (for example, TIME (with a start and end time) or ALLDAY). Activities can also have start and end dates, a location, a title, and a tag.

The CalendarProvider class represents the owner of an activity. A provider can be either enabled or disabled for a calendar.

17.2.2 How to Create a Calendar

Create your own implementations of the CalendarModel and CalendarActivity classes and implement the abstract methods to provide the logic.

Before you begin:

It may be helpful to have an understanding of the CalendarModel and CalendarActivity classes. For more information, see Section 17.2.1, "Calendar Classes."

You may also find it helpful to understand functionality that can be added using other ADF Faces features. For more information, see Section 17.1.2, "Additional Functionality for the Calendar."

To create the calendar model classes:

1. Create a managed bean that will hold logic for the calendar. This bean must:

   • Extend the oracle.adf.view.rich.model.CalendarModel class.

   • Implement the abstract methods.

     For more information about the CalendarModel class, see the ADF Faces Javadoc.

   • Implement any other needed functionality for the calendar. For example, you might add logic that sets the time zone, as in the oracle.adfdemo.view.calendar.rich.model.DemoCalendarBean managed bean in the ADF Faces demo application (for more information about the demo application, see Chapter 2, "ADF Faces Demo Application").

   For more information about creating managed beans, see Section 3.6, "Creating and Using Managed Beans."

2. Create a managed bean that will hold logic for the activities. This bean must:

   • Extend the oracle.adf.view.rich.model.CalendarActivity class.

   • Implement the abstract methods.

   • Implement any other required functionality for the calendar. As an example, see the oracle.adfdemo.view.calendar.rich.model.DemoCalendarActivity managed bean in the ADF Faces demo application.

     Tip:

     If you want to style individual instances of an activity (for example, if you want each provider's activities to be displayed in a different color), then the getTags method must return a string that represents the activity instance. For more information, see Section 17.6.1, "How to Style Activities."

3. Create a managed bean that will hold information and logic for providers.

   • Extend the oracle.adf.view.rich.model.CalendarProvider class.

   • Implement the abstract methods.

   • Implement any other required functionality for the provider.

To create the calendar component:

1. In the Component Palette, from the Data Views section, drag a Calendar and drop it onto a JSF page.

   Tip:

   The calendar component can be stretched by any parent component that can stretch its children. If the calendar is a child component to a component that cannot be stretched, it will use a default width and height, which cannot be stretched by the user at runtime. However, you can override the default width and height using inline style attributes. For more information about the default height and width, see Section 17.3, "Configuring the Calendar Component." For more information about stretching components, see Section 9.2.1, "Geometry Management and Component Stretching."

2. Expand the Calendar Data section of the Property Inspector, and enter an EL expression for Value that resolves to the managed bean that extends the CalendarModel class.

17.3.1 How to Configure the Calendar Component

You configure the calendar using the Property Inspector.

Before you begin:

It may be helpful to have an understanding of the calendar component. For more information, see Section 17.3, "Configuring the Calendar Component."

You may also find it helpful to understand functionality that can be added using other ADF Faces features. For more information, see Section 17.1.2, "Additional Functionality for the Calendar."

To configure a calendar:

1. With the calendar component selected, expand the Common section of the Property Inspector, and set the following:

   • View: Select the view that should be the default when the calendar is displayed. Users change this value when they click the corresponding button in the calendar's toolbar. Valid values are:

     • day

     • list

     • month

     • week

   • StartDayOfWeek: Enter the day of the week that should be shown as the starting day, at the very left in the monthly or weekly view. When not set, the default is based on the user's locale. Valid values are:

     • sun

     • mon

     • tue

     • wed

     • thu

     • fri

     • sat

   • StartHour: Enter a number that represents the hour (in 24 hour format, with 0 being midnight) that should be displayed at the top of the day and week view. While the calendar (when in day or week view) starts the day at 12:01 a.m., the calendar will automatically scroll to the startHour value, so that it is displayed at the top of the view. The user can always scroll above that time to view activities that start before the startHour value.

   • ListType: Select how you want the list view to display activities. Valid values are:

     • day: Shows activities only for the active day.

     • dayCount: Shows a number of days including the active day and after, based on the value of the listCount attribute.

     • month: Shows all the activities for the month to which the active day belongs.

     • week: Shows all the activities for the week to which the active day belongs

   • ListCount: Enter the number of days' activities to display (used only when the listType attribute is set to dayCount).

     Figure 17-5 shows a calendar in list view for the active date May 2 with the listType set to dayCount and the listCount value set to 14.

     Figure 17-5 List View Using dayCount Type

     
     

2. Expand the Calendar Data section of the Property Inspector, and set the following:

   • ActiveDay: Set the day used to determine the date range that is displayed in the calendar. By default, the active day is today's date for the user. Do not change this if you want today's date to be the default active day when the calendar is first opened.

     Note that when the user selects another day, this becomes the value for the activeDay attribute. For example, when the user first accesses the calendar, the current date, May 2, 2011 is the active day. The user can select another day to be the active day by clicking on the day link in the month view. The active day also changes when the user selects a different month or year.

   • TimeZone: Set the time zone for the calendar. If not set, the value is taken from AdfFacesContext. The valid value is a java.util.TimeZone object. By default, time is displayed based on the formatting-locale parameter in the trinidad-config.xml file. For more information, see Section A.6, "Configuration in trinidad-config.xml."

3. Expand the Appearance section of the Property Inspector and set AvailableViews. The value can be one of or a combination of the following:

   • month

   • week

   • day

   • list

   • all

   If you want to enter more than one value, enter the values with a space between. For example, if you want the calendar to use day and week views, you would enter the following:

   day week
   

   Note:

   If all is entered, then all views are available, regardless if one is left out of the list.

   The corresponding buttons will automatically be displayed in the toolbar, in the order they appear in the list.

   If you do not enter day as an available view, then activities in the list and week views will not appear as links to the day view (provided you do not also enter all).

   Note:

   In order to handle an overflow of tasks for a given day in the month view, if you enter month and do not also enter all, then you must also enter day.

4. If you want the user to be able to drag a handle on an existing activity to expand or collapse the time period of the activity, then implement a handler for CalendarActivityDurationChangeListener. This handler should include functionality that changes the end time of the activity. If you want the user to be able to move the activity (and, therefore, change the start time as well as the end time), then implement drag and drop functionality. For more information, see Section 33.7, "Adding Drag and Drop Functionality to a Calendar."

You can now add the following functionality:

• Allow users to create, edit, and delete activities using popup components. For more information, see Section 17.4, "Adding Functionality Using Popup Components."

• Allow users to move activities around on the calendar. For more information, see Section 33.7, "Adding Drag and Drop Functionality to a Calendar."

• Change or add to the toolbar buttons in the toolbar. For more information, see Section 17.5, "Customizing the Toolbar."

• Change the appearance of the calendar and events. For more information, see Section 17.6, "Styling the Calendar."

17.3.2 What Happens at Runtime: Calendar Events and PPR

The calendar has two events that are used in conjunction with facets to provide a way to easily implement additional functionality needed in a calendar, such as editing or adding activities. These two events are CalendarActivityEvent (invoked when an action occurs on an activity) and CalendarEvent (invoked when an action occurs on the calendar, itself). For more information about using these events to provide additional functionality, see Section 17.4, "Adding Functionality Using Popup Components."

The calendar also supports events that are fired when certain changes occur. The CalendarActivityDurationChangeEvent is fired when the user changes the duration of an activity by dragging the end time or by drag and drop to change the start time. The CalendarDisplayChangeEvent is fired whenever the component changes the value of a display attribute, for example when the view attribute changes from month to day.

When a CalendarDisplayChangeEvent is fired, the calendar component adds itself as a partial page rendering (PPR) target, allowing the calendar to be immediately refreshed. This is because the calendar assumes that if the display changed programatically, then the calendar must need to be rerendered. For example, if a user changes the view attribute from day to month, then the calendar is rerendered automatically.

17.4.1 How to Add Functionality Using Popup Components

To add functionality, create the popups and associated components in the associated facets.

Before you begin:

It may be helpful to have an understanding of popup components. For more information, see Section 17.4, "Adding Functionality Using Popup Components."

You may also find it helpful to understand functionality that can be added using other ADF Faces features. For more information, see Section 17.1.2, "Additional Functionality for the Calendar."

To add functionality using popup components:

1. In the Structure window, expand the af:calendar component node so that the calendar facets are displayed, as shown in Figure 17-6.

   Figure 17-6 Calendar Facets in the Structure Window

   
   

2. Based on Table 17-1, create popup components in the facets that correspond to the user actions for which you want to provide functionality. For example, if you want users to be able to delete an activity by clicking it and pressing the Delete key, you add a popup dialog to the activityDelete facet.

   To add a popup component, right-click the facet in the Structure window and choose Insert inside facetName > ComponentName.

   For more information about creating popup components, see Chapter 15, "Using Popup Dialogs, Menus, and Windows."

   Example 17-1 shows the JSF code for a dialog popup component used in the activityDelete facet.

   Example 17-1 JSF Code for an Activity Delete Dialog

   <f:facet name="activityDelete">
     <af:popup id="delete" contentDelivery="lazyUncached">
       <!-- don't render if the activity is null -->
       <af:dialog dialogListener="#{calendarBean.deleteListener}"
                  affirmativeTextAndAccessKey="Yes" cancelTextAndAccessKey="No"
                  rendered="#{calendarBean.currActivity != null}">
         <af:spacer height="20"/>
         <af:outputText value="Are you sure you want to delete this activity?"/>
         <af:panelFormLayout>
           <af:inputText label="Title" value="#{calendarBean.currActivity.title}"
                          readOnly="true"/>
           <af:inputDate label="From" value="#{calendarBean.currActivity.from}"
                         readOnly="true">
             <af:convertDateTime type="date" dateStyle="short"
                                 timeZone="#{calendarBean.timeZone}"
                              pattern="#{calendarBean.currActivity.dateTimeFormat}"/>
           </af:inputDate>
           <af:inputDate label="To" value="#{calendarBean.currActivity.to}"
                         readOnly="true">
             <af:convertDateTime type="date" dateStyle="short"
                                 timeZone="#{calendarBean.timeZone}"
                              pattern="#{calendarBean.currActivity.dateTimeFormat}"/>
           </af:inputDate>
           <af:inputText label="Location" readOnly="true"
                         rendered="#{calendarBean.currActivity.location != null}"
                         value="#{calendarBean.currActivity.location}"/>
         </af:panelFormLayout>
       </af:dialog>
     </af:popup>
   </f:facet>
   

   Figure 17-7 shows how the dialog is displayed when a user clicks an activity and presses the Delete key.

   Figure 17-7 Delete Activity Dialog

   
   

3. Implement any needed logic for the calendarActivityListener. For example, if you are implementing a dialog for the activityDeleteFacet, then implement logic in the calendarActivityListener that can save-off the current activity so that when you implement the logic in the dialog listener (in the next step), you will know which activity to delete. Example 17-2 shows the calendarActivityListener for the calendar.jspx page in the ADF Faces demo application.

   Example 17-2 calendarActivityLIstener Handler

   public void activityListener(CalendarActivityEvent ae)
     {
       CalendarActivity activity = ae.getCalendarActivity();
       if (activity == null)
       {
         // no activity with that id is found in the model
         setCurrActivity(null);
         return;
       }
    
       setCurrActivity(new DemoCalendarActivityBean((DemoCalendarActivity)activity,
            getTimeZone()))
   

4. Implement the logic for the popup component in the handler for the popup event. For example, for the delete dialog, implement a handler for the dialogListener that actually deletes the activity when the dialog is dismissed. For more information about creating dialogs and other popup components, see Chapter 15, "Using Popup Dialogs, Menus, and Windows."

17.5.1 How to Customize the Toolbar

Place the toolbar and toolbar buttons you want to add in custom facets that you create. Then, reference the facet (or facets) from an attribute on the calendar, along with keywords that determine how or where the contained items should be displayed.

Before you begin:

It may be helpful to have an understanding of calendar toolbar customization. For more information, see Section 17.5, "Customizing the Toolbar."

You may also find it helpful to understand functionality that can be added using other ADF Faces features. For more information, see Section 17.1.2, "Additional Functionality for the Calendar."

To customize the toolbar:

1. In the JSF page of the Component Palette, from the Core panel, drag and drop a Facet for each section of the toolbar you want to add. For example, to add the custom buttons shown in Figure 17-9, you would add four facet tags. Ensure that each facet has a unique name for the page.

   Tip:

   To ensure that there will be no conflicts with future releases of ADF Faces, start all your facet names with customToolbar. For example, the section of the toolbar that contains the alignment buttons shown in Figure 17-9 are in the customToolbarAlign facet.

2. In the ADF Faces page of the Component Palette, from the Layout panel, drag and drop a Toolbar to each facet and add toolbar buttons and configure the buttons and toolbar as needed. For more information about toolbars and toolbar buttons, see Section 16.3, "Using Toolbars."

3. In the Property Inspector, from the dropdown menu next to the toolboxLayout attribute, choose Edit.

4. In the Edit Property: ToolboxLayout dialog set the value for this attribute. It should be a list of the custom facet names, in the order in which you want the contents in the custom facets to appear. In addition to those facets, you can also include all, or portions of the default toolbar, using the following keywords:

   • all: Displays all the toolbar buttons and text in the default toolbar

   • dates: Displays only the previous, next, and today buttons

   • range: Displays only the string showing the current date range

   • views: Displays only the buttons that allows the user to change the view

   Note:

   If you use the all keyword, then the dates, range, and views keywords are ignored.

   For example, if you created two facets named customToolbar1 and customToolbar2, and you wanted the complete default toolbar to appear in between your custom toolbars, the value of the toolboxLayout attribute would be the following list items:

   • customToolbar1

   • all

   • customToolbar2

   You can also determine the layout of the toolbars using the following keywords:

   • newline: Places the toolbar in the next named facet (or the next keyword from the list in the toolboxLayout attribute) on a new line. For example, if you wanted the toolbar in the customToolbar2 facet to appear on a new line, the list would be:

     • customToolbar1

     • all

     • newline

     • customToolbar2

     If instead, you did not want to use all of the default toolbar, but only the views and dates sections, and you wanted those to each appear on a new line, the list would be:

     • customToolbar1

     • customToolbar2

     • newline

     • views

     • newline

     • dates

   • stretch: Adds a spacer component that stretches to fill up all available space so that the next named facet (or next keyword from the default toolbar) is displayed as right-aligned in the toolbar. Example 17-3 shows the value of the toolboxLayout attribute for the toolbar displayed in Figure 17-9, along with the toolbar placed in the customToolbarAlign facet. Note that the toolbar buttons displayed in the customToolbarBold facet are right-aligned in the toolbar because the keyword stretch is named before the facet.

   Example 17-3 Value for Custom Toolbar

   <af:calendar binding="#{editor.component}" id="calendar1"
                value="#{calendarBean.calendarModel}"
                timeZone="#{calendarBean.timeZone}"
                toolboxLayout="customToolbarAlign all customToolbarTZ stretch
                               customToolbarBold newline customToolbarCreate"
   . . .
     <f:facet name="customToolbarAlign">
       <af:toolbar>
         <af:commandToolbarButton id="alignLeft" shortDesc="align left"
                                  icon="/images/alignleft16.png" type="radio"
                                  selected="true"/>
         <af:commandToolbarButton id="alignCenter" shortDesc="align center"
                                  icon="/images/aligncenter16.png" type="radio"
                                  selected="false"/>
         <af:commandToolbarButton id="alignRight" shortDesc="align right"
                                  icon="/images/alignright16.png" type="radio"
                                  selected="false"/>
       </af:toolbar>
     </f:facet>
   . . .
   </af:calendar>
   

17.6.1 How to Style Activities

The activityStyles attribute uses InstanceStyles objects to style specific instances of an activity. The InstanceStyles class is a way to provide per-instance inline styles based on skinning keys.

The most common usage of the activityStyles attribute is to display activities belonging to a specific provider using a specific color. For example, the calendar shown in Figure 17-11 shows activities belonging to three different providers. The user can change that color used to represent a provider's activities in the left panel. The activityStyles attribute is used to determine the color displayed for each activity, based on the provider with which it is associated.

Figure 17-11 Activities Styled to Display Color for Different Providers

Note that instead of using a single color, a range of a color is used in the calendar. This is called a color ramp. A color ramp is a set of colors in a color family to represent the different states of activities. For example, Ted's activities use the Blue ramp. Activities whose time span is within one day are displayed in medium blue text. Activities that span across multiple days are shown in a medium blue box with white text. Darker blue is the background for the start time, while lighter blue is the background for the title. These three different blues are all part of the Blue color ramp.

The CalendarActivityRamp class is a subclass (of InstanceStyles) that supports some built-in color ramps and can take a representative color (for example, the blue chosen for Ted's activities) and return the correct color ramp to be used to display each activity in the calendar.

The activityStyles attribute must be bound to a map object. The map key is the set returned from the getTags method on an activity. The map value is an InstanceStyles object, most likely an instance of CalendarActivityRamp. This InstanceStyles object will take in skinning keys, and for each activity, styles will be returned.

Before you begin:

It may be helpful to have an understanding of calendar styles. For more information, see Section 17.6, "Styling the Calendar."

You may also find it helpful to understand functionality that can be added using other ADF Faces features. For more information, see Section 17.1.2, "Additional Functionality for the Calendar."

To style activities:

1. In your CalendarActivity class, have the getTags method return a string set that will be used by the activityStyles attribute to map the returned string to a specific style. For example, to use the different color ramps for the different providers shown in Figure 17-11, you must return a string for each provider. In this case, an activity belonging to the current user might return Me, an activity belonging to Mary might return MJ, and an activity belonging to Ted might return TC. For more information about implementing the CalendarActivity class, see Section 17.2.2, "How to Create a Calendar."

2. Create a map whose key is the set returned from the getTags method, and whose value is an InstanceStyles object (for example, a CalendarActivityRamp instance).

   For example, to use the different color ramps shown in Figure 17-11, you would create a map using the values shown in Table 17-2.

   Table 17-2 Map for activityStyles Attribute

   Key (String Set)	Value (InstanceStyles Object)
   {"Me"}	CalendarActivityRamp.getActivityRamp (CalendarActivityRamp.RampKey.RED)
   {"LE"}	CalendarActivityRamp.getActivityRamp (CalendarActivityRamp.RampKey.ORANGE)
   {"TF"}	CalendarActivityRamp.getActivityRamp (CalendarActivityRamp.RampKey.BLUE)

   
   

3. In the Structure window, select the calendar component, and in the Property Inspector, bind the activityStyles attribute to the map.

17.6.2 What Happens at Runtime: Activity Styling

During calendar rendering for each activity, the renderer calls the CalendarActivity.getTags method to get a string set. The string set is then passed to the map bound to the activityStyles attribute, and an InstanceStyles object is returned (which may be a CalendarActivityRamp).

Using the example:

• If the string set {"Me"} is passed in, the red CalendarActivityRamp is returned.

• If the string set {"LE"} is passed in, the orange CalendarActivityRamp is returned.

• If the string set {"TF"} is passed in, the blue CalendarActivityRamp is returned.

17.6.3 How to Customize Dates

If you want to display something other than the date number string in the day header of the monthly view, you can bind the dateCustomizer attribute to an implementation of a DateCustomizer class that determines what should be displayed for the date.

Before you begin:

It may be helpful to have an understanding of calendar styling. For more information, see Section 17.6, "Styling the Calendar."

You may also find it helpful to understand functionality that can be added using other ADF Faces features. For more information, see Section 17.1.2, "Additional Functionality for the Calendar."

To customize the date string:

1. Create a subclass of the oracle.adf.view.rich.util.DateCustomizer class. This subclass should determine what to display using the following skinning keys:

   • af|calendar::day-header-row: In day view, customize the day of the week in the header. For example, replace "Thursday" with "Thu".

   • af|calendar::list-day-of-month-link: In list view, customize the text for the day of the month link. For example, replace "Jan 1" with "New Year's Day".

   • af|calendar::list-day-of-week-column: In list view, customize the day of the week in the left list column. For example, replace "Thursday" with "Thu".

   • af|calendar::week-header-day-link: In week view, customize the date link for each date in the header. For example, replace "Sun 1/1" with "New Year's Day".

   • af|calendar::month-grid-cell-header-misc: In month view, add miscellaneous text to the empty area of the cell header. For example, on Jan 1, add the text "New Year's Day".

   • af|calendar::month-grid-cell-header-day-link: In month view, customize the date link labels in the cell header. For example, replace "5" with "-34".

     Example 17-4 shows the DemoDateCustomizer class that displays the week number in the first day of the week, and instead of the day of the month, a countdown number to a specific date, as shown in Figure 17-10.

   Example 17-4 Date Customizer Class

   public class MyDateCustomizer extends DateCustomizer
   {
     public String format(Date date, String key, Locale locale, TimeZone tz)
     {
    
       if ("af|calendar::month-grid-cell-header-misc".equals(key))
       {
    
        // return appropriate string
    
       }
       else if ("af|calendar::month-grid-cell-header-day-link".equals(key))
       {
    
         // return appropriate string
       }
    
     return null;
    
     }
    
   }
   

2. In a managed bean, create an instance of the DateCustomizer class, for example:

   private DateCustomizer _dateCustomizer = new DemoDateCustomizer();
   

3. In the calendar component, bind the dateCustomizer attribute to the DateCustomizer instance created in the managed bean.