Hi,
I found out how to specify event type for event through visual editor.
I am totally newbie on visual editor or bpmn2. :(
Hope below information that can help someone.
Specify event type for event through visual editor, it should do below steps:
Step1, add a signal property from right click context menu of bpmn2 editor property view
Step2, specify above signal property to the signalRef attribute of signalEventDefinition.
That's all.