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Control Forms

Overview

There are occasions when a single logical transaction requires data from several forms. It is possible to use a parent form and a series of child auxiliary forms, but this requires that each auxiliary form returns to the parent form before the user can select the next form.

A Control form is a special type of parent for a group of auxiliary forms. It has the following characteristics:

A mixture of a Control form and Auxiliary forms can be constructed as shown in Figure 1.

Figure 1 - A Control form with Auxiliary forms

control_image001.gif

The solid arrows show what the user sees. The dotted arrows show what actually happens.

This arrangement has the following characteristics:

The following options are also available:

The <EXEC> proc contains code which will initialise its data using any initial values that have been defined for the control form as well as all the forms in component variable $form_list$.

Before each child form is activated LP_PRE_PROC is available for pre-processing.

After returning from each child form LP_POST_PROC is available for post-processing.

The following operations are also available:


Control 1 - add an occurrence

CT_CONTROL1.gif

Description

For an overview of all Control forms please go here.

This form is used to create a new occurrence of a single MAIN entity. All screen dialog is performed by a series of child forms which have their identities listed in component variable $FORM_LIST$. All data is passed back from the child forms to the parent control form for updating on the database.

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  

Component Variables (Refer to Component Variables)

Name Description
FORM_VERSION  
INIT_VALUES  
PARAMS  
AUTO_STORE Indicates if <STORE> is to be invoked automatically after the last screen has been processed. If set to NO the user will be given a choice at the last screen - REVIEW or STORE. This can be populated by using the Extra Parameters field in the menu database.
FORM_LIST An indexed list which identifies the child forms to be processed. This should be populated by code in the LP_INITIALISE proc.
NEXT_FORM Holds the identity of the next form to be processed.

Control 2 - add a MANY in a ONE-to-MANY relationship

CT_CONTROL2.gif

Description

For an overview of all Control forms please go here.

This form is used to create a new occurrence of a MANY entity in a ONE to MANY relationship. The identity of ONE must be passed as a parameter when the form is first activated. All screen dialog is performed by a series of child forms which have their identities listed in component variable $FORM_LIST$. All data is passed back from the child forms to the parent control form for updating on the database.

Contents

Bound Objects

Source Entity Source Field Target Entity Target Field
ONE N/A   N/A
MANY N/A   N/A

Local Constants (Refer to Local Constants)

Name Expression Description
FORM_VERSION 01.000.000  

Component Variables (Refer to Component Variables)

Name Description
FORM_VERSION  
INIT_VALUES  
PARAMS  
AUTO_STORE Indicates if <STORE> is to be invoked automatically after the last screen has been processed. If set to NO the user will be given a choice at the last screen - REVIEW or STORE. This can be populated by using the Extra Parameters field in the menu database.
FORM_LIST An indexed list which identifies the child forms to be processed. This should be populated by code in the LP_INITIALISE proc.
NEXT_FORM Holds the identity of the next form to be processed.

Control 3 - read/write access

CT_CONTROL3.gif

Description

For an overview of all Control forms please go here.

This form is used to modify the details of a selected occurrence of entity MAIN. It will retrieve the selected occurrence, then pass the data to a series of child forms which have their identities listed in component variable $FORM_LIST$. These forms will display the data and allow modifications. All data is passed back from the child forms to the parent control form for updating on the database.

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  

Component Variables (Refer to Component Variables)

Name Description
FORM_VERSION  
PARAMS  
AUTO_STORE Indicates if <STORE> is to be invoked automatically after the last screen has been processed. If set to NO the user will be given a choice at the last screen - REVIEW or STORE. This can be populated by using the Extra Parameters field in the menu database.
FORM_LIST An indexed list which identifies the child forms to be processed. This should be populated by code in the LP_INITIALISE proc.
NEXT_FORM Holds the identity of the next form to be processed.

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