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Use

Web Dynpro ABAP Framework allows you to create your own input help components.

Note

Before programming your own input helps, see whether your input helps can be depicted using an ABAP Dictionary search help . If you consistently use the search help and thus the default input helps, your Web Dynpro application is more uniform. In addition, the ABAP Dictionary search help allows you to maintain a personal values list (favorites) . You can also formulate complex search queries using the selection options for the individual search fields . If you want to make these functions available to users for freely programmed input helps, additional development and maintenance efforts must be planned.

A component to be used as input help must implement the IWD_VALUE_HELP interface (see Working with Web Dynpro Component Interfaces ). Once the freely programmed input help has been linked to a context attribute, the input help is automatically available for every InputField linked to this attribute.

Interface IWD_VALUE_HELP

When programming with interface IWD_VALUE_HELP, take note of the following:

  • The SET_VALUE_HELP_LISTENER method for the interface controller of IWD_VALUE_HELP can be called only by Web Dynpro Framework. The framework uses this method to pass a callback interface to the input help component. The input help component can use this interface to tell the framework that it is to be closed, for example, if data has been selected, if Cancel has been pressed, or if an error has occurred. This interface contains the two attributes F4_CONTEXT_ELEMENT and F4_ATTRIBUTE_INFO as well. They describe the context element for which the F4 help has been requested.

  • The VH_WINDOW_CLOSED and VH_WINDOW_OPENED events of the component interface may only be triggered by the framework. The events indicate the points in time when the input help window is closed or opened. When implementing the IWD_VALUE_HELP component interface, these events should be copied to the component interface of the input help component to make them available in the calling component and to allow its event handlers to register these events.

  • The IWD_VALUE_HELP component interface has the WD_VALUE_HELP interface view. The views to be displayed in the input help window must be embedded into the WD_VALUE_HELP window, which belongs to the interface view.

  • Once the input help component has been created by Web Dynpro Framework, the SET_VALUE_HELP_LISTENER method is called (also by the framework) so the IF_WD_VALUE_HELP_LISTENER interface can be passed to the input help component. This interface contains the CLOSE_WINDOW method. This method can be used to close the input help window.

Attachment to a Context Attribute

You attach a freely programmed input help in analogy to the attachment of an OVS input help by following these steps:

  1. Creating an input help component and implementing the IWD_VALUE_HELP component interface.

  2. Creating a component usage for the input help component in your application component.

  3. Attaching the component usage to the context attribute. In this case, for the input help mode choose free (either when creating the attribute or later in its properties table) and specify the respective component usage.

Context Change Log for Freely Programmed Input Help

When you work with a freely programmed input help, you can still use the Context Change Log function. Note, however, that the values selected by the user are not automatically written to the change table; you need to program the entry explicitly (see OVS Value Help and Context Change Log ).