[TIMOB-10005] Only fire 'postlayout' when the layout actually changes

[sptramer]

Note that this can still result in extraneous events if multiple resizes/repositionings are done during a layout pass, since the end result delivered to the user will only grab the latest available size/rect and not necessarily the values at the time of the layout. It may actually be useful to pass, as the event object, the rect (not size) of the view at layout time, giving a way to detect which pass was the "final" one.

TICKET

[vishalduggal]

Code reviewed. ACCEPTED

[vishalduggal]

Functional Passed. The number of postlayout events is reduced. This does introduce a behavior change for IOS where the postlayout event is no longer propagated. Have verified that MW does not propagate the event either. Will wait for confirmation from Android about event behavior before merge.

Old Event Stream from Sample App

[INFO] Button postlayout [object TiUIButton]
[INFO] Window postlayout [object TiUIButton]
[INFO] Label postlayout [object TiUILabel]
[INFO] Window postlayout [object TiUILabel]
[INFO] Window postlayout [object TiUIWindow]
[INFO] Button postlayout [object TiUIButton]
[INFO] Window postlayout [object TiUIButton]
[INFO] Button postlayout [object TiUIButton]
[INFO] Window postlayout [object TiUIButton]
[INFO] Window postlayout [object TiUIWindow]
[INFO] Button postlayout [object TiUIButton]
[INFO] Window postlayout [object TiUIButton]

New Event Stream from Sample App

[INFO] Window postlayout [object TiUIWindow]
[INFO] Button postlayout [object TiUIButton]
[INFO] Label postlayout [object TiUILabel]
[INFO] Button postlayout [object TiUIButton]
[INFO] Label postlayout [object TiUILabel]

[sptramer]

The latest event discussions from the technical leads and the architecture group have decided that it is inappropriate for postlayout to bubble upwards. A bug should be filed against Android if they do propagate it.

[ayeung]

I just checked the code, and Android does bubble up the event for postlayout. I will file a bug for this, so it will be changed on the android side.

[vishalduggal]

Since Android will file a parity ticket accepting this PR. ACCEPTED