Marcio Galli wrote: > @Paul, > > What is your use case BTW? when you say "update views" based on mutations, > is the goal is to let the user know what is going on? Or you actually > performing other mutations back to the DOM or logging things or creating > reports?
For example: if you start the Firefox Inspector (in the tools menu), you have what we call a highlighter (a rectangle over the page that shows you what node is selected). I want to know when this node is removed and then hide the rectangle. > > m > > > On Thu, Oct 11, 2012 at 4:27 PM, Jonas Sicking <jo...@sicking.cc> wrote: > > > On Thu, Oct 11, 2012 at 6:04 AM, Paul Rouget <p...@mozilla.com> wrote: > > > Paul Rouget wrote: > > >> Context: in the firefox devtools, we need to track some nodes and update > > >> different "views" based on what's happening to this node (show its > > parents, > > >> show its child, show its attributes, …). > > >> > > >> The new Mutation observers are very helpful. But there's one thing I am > > not > > >> really sure how to handle correctly . > > >> > > >> When a node gets detached (parent.removeChild(node)) or reparented, I > > need to > > >> be notified. > > >> > > >> My current idea is to listen to "childList" mutations from the parent, > > >> then, on this mutation, check if the node is still part of the children > > of > > >> the parent, if not, check if it has a parent, if so, the node has been > > >> *relocated*, then I need re-listen to a "childList" mutation from this > > >> new parent, if no parent, the node has been *detached*. > > >> > > >> I was wondering if there was any better way to do that. > > > > > > Another way to do it is to listen to subtree mutations from the > > documentElement, > > > and then check if the targeted node is part of the removeNodes list. > > > > You also would have to check if any of the the node's ancestors is > > part of the removeNodes list. > > > > > Would that deteriorate the performance? > > > > That is obviously more work that has to be done both by the platform > > and by the webpage, so yes, it's worse performance. How much work I > > couldn't say offhand. > > > > It would be worth bringing this use-case to the webapps WG where > > MutationObservers are defined. Especially getting notifications when a > > node is moved in and out of a document seems like it would be worth > > having explicit notifications about. > > > > / Jonas > > _______________________________________________ > > dev-platform mailing list > > dev-platform@lists.mozilla.org > > https://lists.mozilla.org/listinfo/dev-platform > > > > > > -- > www.telasocial.com -- Paul _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
