Tersus: Selection Field

Selection FieldDate: Apr 9, 2012Selection Field is used to display on the screen a drop-down list and let the user choose one the listed values (compare with Button Group).Selection Field contains the following elements:

<Value> - You may set it to the initial value you want to display on screen. When the user selects one of the listed values, <Value> is updated accordingly.

<Options> (repetitive element): The list of possible values that can be selected.

<Placeholder Text> - Text to display for the empty option, if one is required (i.e. non selection). If specified, the empty option will be listed first in the drop-down list, before the options specified in <Options>. If the user selects this option, <Value> will be empty.

<Caption> - If exists, a label with the element's name (still under development - the ability to set a different caption) is displayed on screen just before the selection field. On a narrow screen (e.g. an iPhone), the label appears in a separate line (see screenshot). On wider screens (e.g. iPad), the label appears in the same line.

<On Change> - An action performed when a value is selected.

Notice that <Value> and <Options> should be of the same type (e.g. both Text, both Date, or whatever data type you want). If they have a composite data type, the drop-down list diplays the first text field it contains. For example, if it contains a numeric field named Id and a text field named Name, then the Name values of each of the data structures in <Options> is diplayed.
Sample Modeling:

Selections.tersus uses both Button Group and Selection Field to implement the same selection (in this particular case, Button Group seems to be a better fit):