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Hidden Forms / Services

Overview

These are called "hidden" forms because they have no dialog with the user. They are called from other functions in order to perform a service. They will usually require parameters to be passed from the parent to identify the object on which they should perform their activity, and will usually have a result to pass back.

This type of form can be constructed as a self-contained service so that it may be run on a remote device, thus reducing the need to transmit data over the network unnecessarily.

Note that non-modality can only be achieved when an edit or display statement is encountered, and as a service cannot contain either of these it can only ever be modal.

If the service is activated with the <exec> operation it will terminate and be removed from the component pool when the operation has completed. If a service needs to be reused without being instantiated each time then it must be activated with a different operation name.

The following operation names are reserved words:-

INIT Invoked automatically when the component is instantiated.
EXEC Activates the <exec> trigger. Note that completion of this operation will cause the component to terminate (return is treated the same as exit).
ACCEPT Activates the <accept> trigger.
QUIT Activates the <quit> trigger.
CLEANUP Invoked automatically when the component is terminated.

Service components cannot access global objects such as procs and variables. Standard proc names can still be used provided that they are satisfied with a locally-defined entry. The <quit> trigger contains a series of include procs which have the same name as global procs, but which contain different code to deal with the requirements of self-contained services. All these standard include procs are maintained in the STD library.


Hidden 1 - single operation, read only

CT_HIDDEN1.gif

Description

For an overview of all Hidden forms please go here.

This type of function does not update the database, it is read-only. It will usually have only one operation (the <exec> trigger) which calls local proc LP_PROCESS for its processing.

Buttons

N/A

Contents

Bound Objects

Source Entity Source Field Target Entity Target Field
MAIN N/A   N/A

Local Constants (Refer to Local Constants)

Name Expression Description
FORM_VERSION 01.000.000 To be incremented each time the component is changed.

Component Variables (Refer to Component Variables)

Name Description
FORM_VERSION  
PARAMS  
MSGDATA Message Data - required by STOREQ_PROC to pass message back to parent.
MSGDST Message Destination - required by STOREQ_PROC to pass message back to parent.
MSGID Message ID - required by STOREQ_PROC to pass message back to parent.

Hidden 2 - single operation, store with commit

CT_HIDDEN2.gif

Description

For an overview of all Hidden forms please go here.

This type of function updates the database and follows with a COMMIT. It will usually have only one operation (the <exec> trigger) which calls local proc LP_PROCESS for its processing.

Buttons

N/A

Contents

Bound Objects

Source Entity Source Field Target Entity Target Field
MAIN N/A   N/A

Local Constants (Refer to Local Constants)

Name Expression Description
FORM_VERSION 01.000.000 To be incremented each time the component is changed.

Component Variables (Refer to Component Variables)

Name Description
FORM_VERSION  
PARAMS  
MSGDATA Message Data - required by STOREQ_PROC to pass message back to parent.
MSGDST Message Destination - required by STOREQ_PROC to pass message back to parent.
MSGID Message ID - required by STOREQ_PROC to pass message back to parent.

Hidden 3 - single operation, store without commit

CT_HIDDEN3.gif

Description

For an overview of all Hidden forms please go here.

This type of function updates the database, but without a COMMIT as this must be left to the parent form. It will usually have only one operation (the <exec> trigger) which calls local proc LP_PROCESS for its processing.

Buttons

N/A

Contents

Bound Objects

Source Entity Source Field Target Entity Target Field
MAIN N/A   N/A

Local Constants (Refer to Local Constants)

Name Expression Description
FORM_VERSION 01.000.000 To be incremented each time the component is changed.

Component Variables (Refer to Component Variables)

Name Description
FORM_VERSION  
PARAMS  
MSGDATA Message Data - required by STOREQ_PROC to pass message back to parent.
MSGDST Message Destination - required by STOREQ_PROC to pass message back to parent.
MSGID Message ID - required by STOREQ_PROC to pass message back to parent.

Hidden 4 - multi-operation

CT_HIDDEN4.gif

Description

For an overview of all Hidden forms please go here.

This type of function has one or more operations that can be activated multiple times for each instantiation. Provided that the operation ends with a return statement and not an exit it will continue to exist when it completes its processing.

Any operation may include a store and/or commit.

Buttons

N/A

Contents

Bound Objects

Source Entity Source Field Target Entity Target Field
MAIN N/A   N/A

Local Constants (Refer to Local Constants)

Name Expression Description
FORM_VERSION 01.000.000 To be incremented each time the component is changed.

Component Variables (Refer to Component Variables)

Name Description
FORM_VERSION  
PARAMS  
MSGDATA Message Data - required by STOREQ_PROC to pass message back to parent.
MSGDST Message Destination - required by STOREQ_PROC to pass message back to parent.
MSGID Message ID - required by STOREQ_PROC to pass message back to parent.

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