Assignment rules are used to link properties of control elements with variables, properties, etc.
For example, to display the value of a string variable in a text field.
Rules can be created for each property that has a cogwheel icon 
.
Click on the cogwheel icon to open the rule editor for the selected property.
The rule editor opens. The property of the component with which the rule editor was opened is preselected here (in this case “Visible”).
To create a new rule, click on the plus icon in the toolbar.
You have the option of adding a condition to the rule. The input field for the conditions is permanently visible in the rule editor.
To create a new condition, use the plus icon next to “Condition“.
Click on the arrow next to the text box to open a list of all available objects that can be selected.
These are identified by corresponding symbols. This applies to all text boxes. The selection is made by clicking.
A search function is also possible here by writing directly into the text box to search for terms. All matching objects from the search are then displayed.
The symbol at the front changes depending on what has been selected. In the example below, the variable “System.hour” was selected.
By clicking on the pipette symbol 
, the selection can be made in the *old input system if desired. This applies wherever the pipette symbol is displayed.
After defining the condition, a further condition can be added. To add another condition, repeatedly use the plus icon next to “Condition“. This allows you to add as many conditions as you like.
Individual conditions can be deleted by clicking on the dustbin icon 
on the right.
You also have the option of deciding whether it is sufficient for at least ONE of the created conditions to apply or whether ALL conditions must apply. To do this, use the “OR” and “AND” buttons, i.e. Or / And.
Use of the switch is available from the second condition. Before this, it is grayed out.
You can also add groups within the conditions. One or more conditions can then be added to the groups.
In the following example, this would mean Either if the original time is 10 OR (switch to “OR“) if the group block applies.
Within a group, you can also choose between “OR” and “AND” and interact with the same options.
If the first switch were set to “AND“, BOTH the first condition AND the group block would have to be fulfilled with at least ONE of the conditions contained therein.
This allows complex conditions to be defined.
Once you have made all the entries and defined the rule, click on Save to create the rule.
Created rules can be added or deleted via the toolbar. The order can also be changed. The order is important in that the rule processing stops with the first rule that either has no condition or whose condition applies.
Rules are always processed from top to bottom, i.e. they are always processed one after the other.
For properties that have been assigned a rule, the cogwheel icon is highlighted in blue.
To negate values, use the exclamation mark button to the left of the value when creating a rule.
If this button is clicked, it is highlighted in blue and the value is negated.
If you want to output a value directly as text rather than as an element, simply click on the element name. The respective element symbol then changes to quotation marks. In the example below, a property becomes a text.
This means that the text “Page.QHMIButton.Text” itself is output as a string instead of the text in the button.
This would be useful if two identifiers in the system have the same name and you do not want the element itself, but the name at this point.
