The MultiTagViewer has multiple configuration options, some of them common to many other Graphic objects such as Size, Location, IsVisible, IsEnabled, Fonts and Brushes but others are unique.

Let’s take a look at the column configuration options described in the previous sub-chapter.

Using a dynamic image to display different images during Runtime according to the value of the tag.  In the example below, 3 different images were associated to different values (0 – green circular image, 1- yellow circular image, and 2 – red circular image).

An expression is used to evaluate the value returned.  In this example, it is using the current tag value (val) without further conversion.  It is possible to create a C# ternary expression if necessary.  Please take a look at the expression box below to understand the parameters available.

The Logic script has 2 parameters, a ref object val and an integer containing the row index.  With these parameters, it is possible to access any tag from the current row and change the val value.  However, in this example the val already contains the tag’s value from 0 to 2 so the final expression is simply the val object.

Displaying a simple text where the input is disabled.  In this example, the tag value will be directly displayed without any changes so the expression is again the val value.

Displaying a checkbox to represent a Boolean and customizing the text in the expression box.

In this example, the Text is not the tag value, but it is a string “on” or “off” depending on the tag’s value.  Please take a look at the image below to understand how a C# ternary expression is written.

It checks for the Boolean tag of the current row using the index integer parameter.  If it is true, the val value will receive “On”; otherwise, it will receive “Off”.  Since val is a reference parameter, it will return that new value to the grid.

Instead of a ternary expression, it is also possible to concatenate or link the tag’s value to a string or convert the value to a different unit.  In the example below, the next maintenance is concatenated to “(days)” string.

A column can also be changed into a button type as in the next example.  If a button is needed to start or stop a machine in production, a checkbox could be used or a text but there is also the option to use a button.  Within the button, we will create a script to validate a checklist before actually starting or stopping a machine.  We can customize the button text using a ternary expression.

Both a ternary expression and a mouse down event have been added to the button. Let’s review them separately.

Button Text Expression:

The button text expression checks if the machine is running and what text should be displayed.  If the machine is running, the button text will show “Stop”.  If the machine is not running, the button will show “Start”.

Mouse Down Script:

The script is not simply a C# ternary expression.  It allows establishing local variables, calling user functions, using .net framework functions, and writing powerful code.  In this example, we are changing the isRunning tag to true or false depending on the tag’s current state.  The scripts also make use of the input parameters val and index.