====== Screen Events ======

Screen events are events that only occur when the associated screen is being displayed.

{{ :comfilehmi:screenevent:screenevent.png?nolink |screenevent}}

===== Screen Event Types =====

{{ :comfilehmi:screenevent:screenevent2.png?nolink |}}

There are 4 screen event types:

  * 1. When Screen Opens: This event occurs when the screen is first displayed.
  * 2. When Screen Closes: The event occurs when the screen is no longer displayed (e.g. Immediately before transitioning to a different screen).
  * 3. Timer: This event occurs periodically while the screen is being displayed.
  * 4. Monitor by Expression : This event occurs when a variable or expression evaluates to a specified condition.
  * 5. Monitor Device : This event occurs when data in a device's memory meets a specified condition.

===== 1. When Screen Opens =====

Press the down arrow icon next to the event type to add actions to an event.

{{ :comfilehmi:screenevent:screenactionadd.png?nolink |}}

===== 2. When Screen Closes =====

Press the down arrow icon next to the event type to add actions to an event.


===== 3. Timer =====

Press the down arrow icon next to the //Timer// node to add a new timer event.

{{ :comfilehmi:screenevent:screentimeradd.png?nolink |}}

The following window will appear.

{{ :comfilehmi:globalevent:eventtimer1.png?nolink |}}

Specify the period of for which the event will occur.  In this example, the period is set to 1 second.

Add actions to run when the event occurs.

{{ :comfilehmi:screenevent:screentimeradd2.png?nolink |}}


===== 4. Monitor by Expression =====

Press the down arrow icon next to the //Expression// node to add a new expression event.

{{ :comfilehmi:screenevent:screensusikeventadd.png?nolink |}}

Enter the expression specifying the condition that must be met for the event to occur.

{{ :comfilehmi:globalevent:susikwatch.png?nolink |}}

Add actions to be executed when the event occurs.

{{ :comfilehmi:screenevent:screensusikeventadd2.png?nolink |}}

===== 5. Monitor Device =====

Press the down arrow icon next to the //Device// node to add a new device event

{{ :comfilehmi:screenevent:screendevicewatch.png?nolink |}}

Enter the device address to monitor and specify the conditions that must be met for the event to occur.

{{ :comfilehmi:globalevent:devicewatch.png?nolink |}}

Add the actions to be executed when the event occurs.

{{ :comfilehmi:screenevent:screendevicewatch2.png?nolink |}}

----
===== Add Events =====

The following window will appear to provide the ability to add multi-actions to the event.

{{ :comfilehmi:globalevent:eventadd.png?nolink |}}

[[comfilehmi:multiaction:index|What is action?]]

====== Video ======

{{ :comfilehmi:screenevent:screenevent.mp4?850x454 |}}

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