• Custom Controls
• Controls Tutorial

Creating a Control

STEP 1 - Create the Instance

• Define a reference variable for the Custom Container in which you want to place the custom control
• DATA container TYPE REF TO cl_gui_custom_container.
• Define a reference variable for the control object you wish to use
• DATA picture TYPE REF TO cl_gui_picture.
• Create the Custom Container. You must already have created the area 'CUSTOM_CONTAINER' for the Custom Container in the Screen Painter.
• CREATE OBJECT container
      EXPORTING
         container_name = 'CUSTOM_CONTAINER'
         lifetime                = lifetime.

STEP 2 - Register Events

The event mechanism of the Control Framework allows you to use handler methods in your programs to react to events triggered by the control (for example, a double-click).

• Registering the events with the Control Framework
• DATA my_control TYPE REF TO cl_gui_xyz.
• DATA events TYPE cntl_simple_events.
  DATA wa_events TYPE cntl_simple_event.
• wa_events-eventid = event_id .
  wa_events-appl_event = appl_event .
  APPEND wa_events TO events.
• CALL METHOD my_control->set_registered_events
           events = events.
• Defining a handler method
• CLASS lcl_event_receiver DEFINITION.
  PUBLIC SECTION.
  METHODS Event_Handler
     FOR EVENT event_name OF cl_gui_xyz
     IMPORTING event_parameter
               sender .
  ENDCLASS.
• Registering the hander method
• DATA event_receiver TYPE REF TO lcl_event_receiver.
  CREATE OBJECT event_receiver.
  SET HANDLER event_receiver->Event_Handler
               FOR my_control.
• Processing the event
• CLASS lcl_event_receiver IMPLEMENTATION.
  METHOD Event_Handler.
  * Event processing
  ENDMETHOD
  ENDCLASS.

STEP 3 - Use the control

STEP 4 - Destroy the control

• Use the method free to destroy the Custom Control at the frontend. If you no longer need the control container, release it as well:
• CALL METHOD picture->free
       EXCEPTIONS cntl_error   = 1
                    cntl_system_error = 2.
• CALL METHOD container->free
       EXCEPTIONS cntl_error   = 1
                    cntl_system_error = 2
• Pay careful attention to the sequence in which you destroy controls at the frontend. When you destroy a container, all controls in it are automatically destroyed as well. If you have already destroyed a control and try to destroy it again, an error occurs. You can check whether a control has already been destroyed using the method is_alive.
• Delete the reference variables to the custom control and the control container.
• FREE PICTURE.
• FREE CONTAINER.

Event Handling

• See STEP 2 above
• Drag and Drop

Drag and drop allows the user to select an object from one part of a custom control (source) and drop it on another part of a custom control (target). An action occurs in the second part that depends on the object type. Source and target may be either the same control or different controls.

A particular drag and drop behavior is set for each custom control. This behavior may be set globally for all elements of the control (for example, SAP Textedit), or you may be able to define a different behavior for each component (for example SAP Tree). Each behavior consists of one or more descriptions.

A description has the following attributes:

o   DragSrc: Object is the source of a drag and drop procedure

o   DropTarget: Object is the target of a drag and drop procedure

o   Flavor: The flavor describes the type of a drag and drop description. In a drag and drop operation, you can only drop an object onto another if both have at least one common description.

o   Effect: Specifies whether the drag and drop operations copies or moves the object.

o   Effect_In_Ctrl: The drop effect used when you copy or move data within the same control.

• Process Flow of a Drag and Drop Operation
• Example of Drag and Drop Programming
• Context Menu

The context menu (right-hand mouse button or SHIFT+F10 ) allows you to display a context-sensitive menu

• You register for the event context_menu and context_menu_selected using the set_registered_events method.
• Define methods to handle both events

o   Constructing a Context Menu

§  When you implement the handler method for the event context_menu , you must assign the menu to the control. You may need to check the particular context in which the user requested the context menu.

§  You construct the context menu using class CL_CTMENU . Almost all control wrappers pass a context menu object reference as an event parameter of the context_menu event. If this is not the case (for example, SAP Picture), you must create an object of the class CL_CTMENU .

• LOAD_GUI_STATUS - Loads a context menu that you have already defined in the Menu Painter (see below)
• ADD_FUNCTION - Adds a function
• ADD_MENU - Adds a menu that you defined in the Menu Painter
• ADD_SUBMENU - Adds a menu that you defined in the Menu Painter as a submenu
• ADD_SEPARATOR - Adds a separator
• RESET - Reset to initial value
• HIDE FUNCTIONS - Hides a function
• SHOW_FUNCTIONS - Shows a function
• DISABLE_FUNCTIONS - Inactivates a function
• ENABLE_FUNCTIONS - Activates a function

SAP HTML Viewer

• The program SAPHTML_EVENTS_DEMO shows how you can use the SAP HTML Viewer

SAP Calendar Control

SAP TextEdit Control

ALV Grid Control

SAP Container

There are five kinds of SAP Containers:

• SAP Custom Container
  The SAP Custom Container allows you to display controls in an area defined on a normal screen using the Screen Painter.
  Class: CL_GUI_CUSTOM_CONTAINER
• SAP Dialog Box Container
  The SAP Dialog Box container allows you to display controls in an amodal dialog box or fullscreen.
  Class: CL_GUI_DIALOGBOX_CONTAINER
• SAP Docking Container
  The SAP Docking Container allows you to attach a control to any of the four edges of a screen as a resizable screen area. You can also detach it so that it becomes an independent amodal dialog box.
  Class: CL_GUI_DOCKING_CONTAINER
• SAP Splitter Container
  The SAP Splitter Container allows you to display more than one control in a given area by dividing it into cells.
  Class: CL_GUI_SPLITTER_CONTAINER
• SAP Easy Splitter Container
  The SAP Easy Splitter Container allows you to divide an area into two cells with a control in each. The cells are separated by a moveable splitter bar.
  Class: CL_GUI_EASY_SPLITTER_CONTAINER

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