IfElse

Tiny widget that enhances Conditional Visibility feature adding the else/otherwise case

Typical usage scenario

A very often development situation is that:

• you have some condition
• if it is true, display some content
• otherwise, display some other content

In Mendix development a common pattern in this case is to use the Conditional Visibility feature. However, you have to duplicate the logic, repeating your condition twice:

• first for the true case: the condition...
• and then for the otherwise case, with additional negation: not(the condition...)

This can be cumbersome and error-prone, especially if your condition is complicated. For example you can have two containers with Visibility set to:

• $currentObject/Name = 'Some name' and ($currentObject/SearchChangedDate > [%BeginOfCurrentDay%] or $currentObject/SomeAssociatedEntity != empty)
• not($currentObject/Name = 'Some name' and ($currentObject/SearchChangedDate > [%BeginOfCurrentDay%] or $currentObject/SomeAssociatedEntity != empty))

As you can see, it is not immediately apparent that the two are related. Readability and maintainability is low and it will be easy to make a mistake when changing something in future (e.g. extending the condition).

The solution is to use this widget, providing the condition once and two containers for both cases inside.

Usage

• Put the widget where you need it
• Set the If expression to your condition
• Fill the Then placeholder with content for true case
• Fill the Else placeholder with content for otherwise case

The content can be anything, e.g. a simple Text widget or a complex Container with a DataGrid or any other Mendix element.

Demo project

ObjectivityCommons > Test button > IfElse widget section