MES Object Events

Sepasoft MES Module Suite

Events on MES Objects

Events provide the ability to add custom scripting in your application based on certain events. Most MES Objects have specific events that are fired during the life cycle of the object, such as object creation New. The New event fires every time a new instance of an object is created.

Events can be viewed and edited from Project Browser in Ignition Designer > MES Scripts > MES Object Events. Whenever an event is fired, an MESScriptEvent object is passed to the event. You can use this object to get information about the event and the object.

Warning

MES 3.81.6 SP5 and later

You may need to know when an object is saved so that you can trigger another action such as a menu system in the project can be updated. With the Save event, you can evaluate the object saved and take action accordingly. The Save event triggers after the save occurs.

Target use for performance: WARNING: Running scripts on a Save event can negatively affect performance.

Event Types

There are two types of MES Object events:

  • System Events: provided by default and cannot be deleted.
  • Custom Events: can be created and scripts can be added for both system and custom events in the MES Scripts > MES Object Events section of the Project Browser of the Ignition Designer to alter what happens when these events are triggered.   

Adding Scripts to System Events

Scripts can be added to change the standard behavior of system events and add functionality when custom events are triggered. This is done in the MES Scripts > MES Object Events section of the Project Browser of the Ignition Designer. Click on the event and add the script in the Script window.

Warning

System events have default behavior that occurs whenever the event fires. When you add a custom script to an event, the custom script fires overriding the default behavior.

If you also want the default behavior to occur, add event.runDefaultHandler() to the custom script.

Creating New Custom Trigger Event Script

Custom events can be created by right-clicking on Custom Trigger Events in the MES Scripts > Custom Trigger Events section of the Project Browser and selecting Add Script. These events fire whenever they are called using the system.mes.executeMESEvent scripting function.

Code Examples

Add Custom Property to New MES Object

Copy Code
Python
#Create a new parameter collection instance.
params = system.mes.object.parameters.create()
 
#Add parameters to it.
params.put('Kind', 'Dressing')
params.put('Priority', 'High')

#Print the parameter values.
print params.size()

MESScriptEvent Object

Whenever an event occurs, an MESScriptEvent object is passed to the script window. The following object functions are provided to allow you to access the MES Object itself as well as execute any default behavior.

runDefaultHandler()

Description

Executes the built-in logic for the event. This allows pre or post logic to be executed around the built-in logic or completely replace the built-in logic. Note that user events will not have a default handler and no logic will be executed if this function is called.

Syntax

runDefaultHandler()

  • Parameters

None

  • Returns

Nothing

getMESObject()

Description

Returns the MES object that the event is being executed for.

Syntax

getMESObject()

  • Parameters

None

  • Returns

AbstractMESObject - The MES object associated with the event.

getParameters()

Description

Return the MESObjectEventParameters object that contains any parameter values

Syntax

getParameters()

  • Parameters

None

  • Returns

MESObjectEventParameters object

setResult(value)

Description

Set the return result. When a MES events requires a result value, this helper function can be used in place of using the script event.getParameters().put('Result', value)

Syntax

setResult(value)

  • Parameters

boolean Value of the result to return. False will cause the Recipe Event to 'fail out' and abort the intended action (selecting or cancelling a recipe).

  • Returns

Nothing

  • Scope

All

MESObjectEventParameters Object

This object is used with the MESScriptEvent object to pass parameters to the MES object event and holds name value pairs where the name is a string and value is any value type of object. This object is typically used when executing user MES object events to allow passing values to the event script. The system.mes.object.parameters.create() script function can also be used to create a new instance of this object. The following object functions are available:

get()

Description

Get the value of a parameter by name.

Syntax

get(parameterName)

  • Parameters

String parameterName - The name of the parameter to return the value for.

  • Returns

Object - The type return matches the type when the parameter was added to the collection using the put() function. If the parameter name does not exist in the collection, None is returned.

  • Scope

All

Code Snippet

Copy Code
Python
#Create a new parameter collection instance.
params = system.mes.object.parameters.create()
 
#Add parameters to it.
params.put('Kind', 'Dressing')
params.put('Priority', 'High')

#Print the parameter values.
print params.size()

Output

Copy Code
Python
2

put()

Description

Add a name value pair to the parameters collection.

Syntax

put(parameterName, value)

  • Parameters

String parameterName - The name of the parameter to add to the parameters collection.

String value - The value of the parameter.

  • Returns

Nothing

  • Scope

All

Code Examples

Code Snippet

Copy Code
Code
#Create a new parameter collection instance.
params = system.mes.object.parameters.create()
 
#Add parameters to it.
params.put('Kind', 'Dressing')
params.put('Priority', 'High')

#Print the parameter values.
print params.size()

size()

Description

Get the number of parameters in the parameter collection.

Syntax

size()


  • Parameters

None

  • Returns

Integer - description

  • Scope

All

Code Examples

Code Snippet

Copy Code
Code
#Create a new parameter collection instance.
params = system.mes.object.parameters.create()
 
#Add parameters to it.
params.put('Kind', 'Dressing')
params.put('Priority', 'High')

#Print the parameter values.
print params.size()

Output

Copy Code
Code
2

Sepasoft MES Module Suite