ReadContainers and WriteContainers

Applications module

1. General




ReadContainers and WriteContainers form an abstraction level that allow you to define which data is displayed or where it is written on pages of an application. Data is reads with ReadContainers and written with WriteContainers.



These areas can be shown or hidden via the View menu. If you select an application page in the application structure, the ReadContainer / WriteContainer area displays which containers have been defined for this page. In principle, both container types have the same setup. They are broken down into: With ReadContainers, data from the data group, which contains the current applications page, is read. With WriteContainers, data can be written to any data group of the same application. You can also use custom ReadContainers and WriteContainers to integrate custom Java classes.

2. ReadContainer


2.1. General

Every application page has exactly one ReadContainer for the data group, which it is contained in. View pages at the top level of the application structure (i.e. directly beneath the application node) and pages in a system data group are exceptions to this. These pages do not have a ReadContainer and one cannot be created for them.

2. Create ReadContainers

In addition to the predefined ReadContainer on application pages in a data group, custom ReadContainers can be created that enable you to integrate custom Java classes.

Add ReadContainer
Opens a dialog where a new ReadContainer can be created.

Delete ReadContainer
Deletes the currently selected ReadContainer.

Move up / down
Change the order of the containers.

2.3. ReadContainer for free layout tables

For every free layout table on a page, exactly one ReadContainer is created with the "multiInput" type.

2.4. Properties




Beneath the list of ReadContainers, you will find the properties of the ReadContainer currently selected. You can show/hide these by clicking on the title bar.

Name

Displays the name of the ReadContainer.

Type

Displays the type of the ReadContainer:

Application / Data group

Displays the application and data group whose data is read by the ReadContainer.

2.5. Filter criteria




Beneath the properties you will find the filter criteria of the ReadContainer currently selected. You can show/hide this area by clicking on the title bar if the type is "dataGroup" or "userdefined". For "dataGroup" ReadContainers, these are usually already predefined correctly. The filter criteria inform the page which data record is to be displayed. The data restriction using filter criteria corresponds to the WHERE clause in the SELECT statement in the database request. As a page in a data group should only show one single data record, every possible combination of source and target values cannot be selected when editing the filter criteria. This means that a request cannot return more than one data record, which would cause an error when loading the page. The filter criteria are deactivated for "multiInput" ReadContainers as the data displayed in the free layout table is controlled by the pages it integrates.

"Source" column

Displays the source of the filter criteria. The source corresponds to the value that should be used to filter the data in the data group.

"Target" column

Displays the target that the value defined in the source is compared to. If these match, the corresponding data record is displayed.

Edit criterion
Displays a page where the filter criterion can be edited. The help for the settings on this page can be accessed by clicking on the question mark symbol.

2.6. Bindings




Bindings link the data read via the ReadContainer to the application elements on the page. Every element that has a binding is displayed in this list.

"Control title" column

The title of the element is shown here.

"Control type" column

The control type of the element is shown here.

"Data field" column

Displays the data type of the data field linked to the element.

Delete binding
Deletes the binding currently selected.

3. WriteContainer


3.1. General

Every application page automatically has a WriteContainer for the data group, which it is contained in. WriteContainers can be created on all pages except for View pages at the top level of the application structure (i.e. directly beneath the application node). Without a WriteContainer, the data record cannot be deleted.

3.2. Create WriteContainer


Add WriteContainer
Opens a dialog where a new WriteContainer can be created.

Delete WriteContainer
Deletes the currently selected WriteContainer.

Move up / down
Change the order of the containers.

2.3. WriteContainer for free layout tables

For every free layout table on a page, exactly one WriteContainer is created with the "multiInput" type.

3.4. Properties




The properties of WriteContainers correspond to those of ReadContainers.

Trigger workflow

This additional setting means that a data group event handler, which listens to the same data group, is triggered in a process, as soon as a Save button is clicked on on the page that contains the WriteContainer - meaning the data record is saved. If this setting is not activated, the event handler will not respond and the subsequent process steps will not be triggered. This is useful when constructing wizards that lead the users through multiple edit pages in the browser, for example. By activating the "Trigger workflow" setting, you can control that the event handler is only triggered when the Save button on the last page of the wizard is clicked on.

3.5. Filter criteria




Beneath the properties you will find the filter criteria of the WriteContainer currently selected. You can show/hide this area by clicking on the title bar if the type is "dataGroup" or "userdefined". For "dataGroup" WriteContainers, these are usually already predefined correctly. The filter criteria inform the page which data record is to be saved. The data restriction using filter criteria corresponds to the WHERE clause in the UPDATE statement in the database request. As a page in a data group should only save one single data record, every possible combination of source and target values cannot be selected when editing the filter criteria. This means that a request cannot edit more than one data record, which would cause an error when saving the page. The filter criteria are deactivated for "multiInput" WriteContainers as the data saved in the free layout table is controlled by the pages it integrates.

"Source" column

Displays the source of the filter criteria. The source corresponds to the value that should be used to filter the data in the data group.

"Target" column

Displays the target that the value defined in the source is compared to. If these match, the corresponding data record is used for saving the data.

Edit criterion
Displays a page where the filter criterion can be edited. The help for the settings on this page can be accessed by clicking on the question mark symbol.

3.6. Bindings




Application elements, which have a binding, can be added or edited here. Elements can also be dragged from the workspace to the Bindings area via drag & drop.

"Control title" column

The title of the element is shown here.

"Control type" column

The control type of the element is shown here.

"Data field" column

Displays the data type of the data field linked to the element.

Delete binding
Deletes the binding currently selected. Add binding
Displays a page where a new binding can be created. The help for the settings on this page can be accessed by clicking on the question mark symbol.

Edit binding
Displays a page where the binding currently selected can be edited. The help for the settings on this page can be accessed by clicking on the question mark symbol.

Binding löschen
Löscht das aktuell markierte Binding.