9 3 Overview of Pull Down Layout And Processing Logic

LANSA Application Design

9.3 Overview of Pull Down Layout And Processing Logic

When an action bar choice is selected by positioning the screen cursor and pressing enter, a pull down menu of the choices associated with the selected action bar option will appear like this example:

   1   Action 1  Action 2  Action 3  Action 4  Action 5 Action 6 

   2  _________________________________________________________

   3            |                        |

   4            | 1. Choice No 1         |                             

   5            | 2. Choice No 2         |                             

   6            | 3. Choice No 3  F16    |                             

   5            | 4. Choice No 4         |                             

   5            | 5. Choice No 5         |                             

   7            |________________________|         

 

Note the selection field in the upper left corner of the pull down.

It is aligned under "Action 2", which indicates that "Action 2" was selected from the action bar.

This pull down shows the choices that are associated with action bar option "Action 2".

In this example, there are 5 pull down choices.

There may be from 1 to 9 choices in any pull down window. It is a CUA 1989 requirement that each pull down has at least one choice.

The length of the pulldown and therefore the amount of the underlying panel body that it overlays varies with the number of choices that appear in it.

In the leftmost pulldown (or rightmost in a bi-directional language), the last pull down choice should be "Exit".

This will be included automatically by LANSA provided that you have left at least one free space in the first pull down.

Pull down choices are numbered consecutively from top to bottom.

The number appears to the left of the choice (or to the right in bi-directional languages).

If the number is not shown, and is replaced by an "*", it means that the choice is currently "unavailable". You cannot select an unavailable choice or use any accelerator key associated with it.

Normally a pull down choice is tagged as unavailable because some other choice must be used first. For instance a pull down choice "Edit a Document" may remain unavailable until you use the choice "Open a Document Folder".

Note that there is a difference between an "unavailable" choice and one that you are not authorized to use.

When you are not authorized to use a pull down choice, it disappears altogether from the pull down menu, and any following choices bunch up and re-number to cover the gap it leaves.

Refer to 9.13 Action Bar Security Considerations for more details.

RDML functions can control the availability and unavailability of pull down choices by using the SET_ACTION_BAR built in function.

At the top left (or right for bi-directional languages) a selection field appears.

This can be used to enter the number associated with the pull down choice that you wish to use.

Pull down choices can also be selected by positioning the cursor on the same line as the required choice and pressing enter. The cursor must remain within the confines of the pull down menu's borders if this option is used.

The third choice, shown in the example pull down, has the text "F16" on the right of the choice text.

By the CUA 1989 standards, this text indicates that function key 16 can also be used to select this pull down choice.

Function key 16 is called an "accelerator key".

Not only can you use it to select the choice when the pull down menu is displayed, but also directly from the action bar (without bothering to show the pull down), and also directly from any underlying panel/function, without even bothering to switch to the action bar.

Accelerator keys can be used by experienced users to "fast path" through applications without having to bother with the action bar or pull down choices and interactions.

Where an accelerator key is associated with a pull down choice you must include the CUA 1989 prescribed "Fnn" text manually. This feature is not automatically implemented.

You can move around the pull down and action bar by using the cursor movement keys, but generally the quickest way on NPTs (non-programmable terminals) is to use the Tab keys.

Use the Tab keys to tab directly from the pull down back to, and around, the action bar in either direction.

The tab keys will not allow you to tab back into the "panel body" when the pull down is on display.

If you tab back to the action bar and press enter you will cause another pulldown to be selected. The current pull down will disappear and be replaced by the new one you selected.

Even if you force the cursor back into the panel body, you still cannot (re)activate the underlying panel. You must cancel the pull down or switch back to the panel body first.

Other function keys available when working from an action bar would normally include Exit, Cancel, Switch and any enabled Accelerator keys.

These are described in detail in the following sections.

The text that you use to identify each pull down choice should be set up according to the guidelines prescribed by CUA 1989.