[TAPESTRY-1100] EventListener called several times for a single form event if caching disabled

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 4.1.1
• Fix Version/s: 4.1.1
• Component/s: tapestry-core
• Environment: tested under winXP SP2 + JDK1.5.0_07 + tomcat 5.5.17
• Assignee: Jesse Kuhnert
• Reporter: Christian Dutaret
• Created: 28/Sep/06 11:34
• Updated: 02/Nov/06 23:04
• Resolved: 02/Nov/06 23:04

Description

I have a page with 2 @PropertySelection components (A and B). An EventListener listens to onchange events on A, and changes the content of B accordingly. When caching is enabled (-Dorg.apache.tapestry.disable-caching=false), everything works as expected.
On each onchange event, the dojo console indicates that the content of B has been updated, and that a js script registering the onchange event has been executed.

If caching is disabled (-Dorg.apache.tapestry.disable-caching=true), the behavior is different :

• on the first onchange event, the listener is called once as expected
• on the second onchange event, the listener is called twice
• on the third onchange event, the listener is called four times.
• etc

Having a closer look at the dojo console output, it appears that the form event registration script creates a different form event ID each time the listener is called (when caching is enabled, the form event ID remains the same). It seems that each response creates a new registration, instead of overwriting the existing one. This would explain the observed behavior.