TAB-CONTROL
A Tab-Control holds one or more Tabs that can be activated by the user, one at a time. It is commonly used to display several pages of controls on the same screen. When a Tab is clicked, the corresponding page is made visible. Tabs can contain graphics, text or both.
Placing controls inside a Tab-Control
There are two types of Tab-Control:
• the standard Tab-Control,
• the Tab-Control with the Allow-Container style.
The standard Tab-Control is not a real container, it’s just an area with some buttons that produce the CMD-TABCHANGED event when clicked. It’s program duty to display controls at the proper coordinates to make them appear over the Tab-Control. The Line and Col properties of the controls you display inside a standard Tab-Control are relative to the window, not to the Tab-Control. This is a legacy implementation supported for compatibility with ACUCOBOL-GT.
The Tab-Control with the Allow-Container style instead is a real container and the runtime takes care of displaying the correct set of controls when the user switches from one page to another. The Tab-Control content can be defined in the Screen Section of the program by setting the tab-group and tab-group-value clauses of a group of controls to the name of the Tab-Control. For example, the following Screen Section snippet defines a Tab-Control with 4 fields inside, 2 in the first page and 2 in the second page:
03 tc-1 tab-control allow-container relative-offset line 3, col 3, lines 10 cells, size 30 cells tab-to-add ("Page 1", "Page 2") . 03 tc-1-page-1 tab-group tc-1, tab-group-value 1. 05 ef-1 entry-field line 2, col 2, size 10 cells. 05 ef-2 entry-field line 4, col 2, size 10 cells. 03 tc-1-page-2 tab-group tc-1, tab-group-value 2. 05 ef-3 entry-field line 2, col 2, size 10 cells. 05 ef-4 entry-field line 4, col 2, size 10 cells. |
Controls can also be dynamically added to Tab-Control pages by using a Format 2 DISPLAY statement. For example, the following statements add two new fields to the above Tab-Control, one in the first page and the other in the second page:
display entry-field upon tc-1-page-1 line 6, col 2, size 10 cells handle ef-5. display entry-field upon tc-1-page-2 line 6, col 2, size 10 cells handle ef-6. |
The page index can be used instead of the screen group to specify the destination page. The above statements could be replaced by these equivalent statements:
display entry-field upon tc-1(1) line 6, col 2, size 10 cells handle ef-5. display entry-field upon tc-1(2) line 6, col 2, size 10 cells handle ef-6. |
The Line and Col properties of the controls you display inside a Tab-Control with the Allow-Container style are relative to the Tab-Control as long as you set the Relative-Offset style as well.