Jim Mathies [:jimm] Reporter
	Description • 11 years ago

Currently you can zoom the start tab. We need to find a way to disable zoom on certain content pages.

	Matt Brubeck (:mbrubeck)
	Comment 1 • 11 years ago

One way to do this is to get <meta name="viewport"> working in Metro (bug 801186) and then add <meta name="viewport" content="user-scalable=no"> to about:start and any other pages that shouldn't zoom.

	Jim Mathies [:jimm] Reporter
	Comment 2 • 11 years ago

this isn't as critical as some others, think it can wait.

	Sam Foster [:sfoster] (he/him)
	Comment 3 • 11 years ago

I dont understand why we would want to go out of our way to prevent zoom on about:start? It should be treated like any other web page IMO, and if I have trouble reading or tapping on the exact target I need for whatever reason, I should be able to zoom and pan to mitigate that.

	Sam Foster [:sfoster] (he/him)
	Comment 4 • 11 years ago

I move to WONTFIX this. I think zooming would be useful today. At worst you get large tiles and have to pan around, at best we improve accessibility and usability for high-res/high-density displays. Also, in the future we want to look at semantic zooming which requires normal zooming to work first. Yuan, Asa what's the thinking behind preventing zoom in the start page?

	Asa Dotzler [:asa]
	Comment 5 • 11 years ago

This is tricky.  Firefox Start is sort of half way between chrome and content.  We don't allow zooming in the Firefox app bar's auto-complete pop-up which is very similar. (note: we do allow selection in the auto-complete results but it doesn't trigger a contextual app bar so it's probably not behaving as we'd like.) 

I'm also in favor of doing smart things with zoom on Firefox Start (semantic zooming, zoom to tile group, etc.) but right now we don't do anything smart and so zoom feels kind of broken.  I lean towards disabling it until we make it smarter. 

Yuan, what do you think?

	Yuan Wang(:Yuan) – Mobile Firefox Design Lead
	Comment 6 • 11 years ago

I agree with Asa.
Eventually I hope the start page will have semantic zoom built in. Currently it does feel kind of broken. I think it's wise to disable zoom for now.

	Kartikaya Gupta (email:kats@mozilla.staktrace.com)
	Comment 7 • 11 years ago

Note that if you want to implement this without implementing meta-viewport it should be possible to do. Once I re-fix bug 937688 you just need to call APZCTreeManager::UpdateZoomConstraints with the right arguments to disable zooming on the about:start page. Implementing meta viewport would let you do this in a generic way but you could hard-code it for about:start.

	Rodrigo Silveira [:rsilveira] [:rodms] Assignee
	Comment 8 • 11 years ago

I'll work on the temporary solution without meta-viewport.

	Rodrigo Silveira [:rsilveira] [:rodms] Assignee
	Comment 9 • 11 years ago

Calling UpdateZoomConstraints on first paint to make sure viewId is set. 

Whenever I open the console and go back to start screen it enables zooming again, hence the ToolPanelHidden processing. Both presShell and view ID are the same though, not sure why it loses the zoom constraints setting.

	Jim Mathies [:jimm] Reporter
	Comment 10 • 11 years ago

Would you mind updating those message strings to match the other apzc messages?

	Matt Brubeck (:mbrubeck)
	Comment 11 • 11 years ago

Comment on attachment 8337171 [details] [diff] [review]
Patch v1

Review of attachment 8337171 [details] [diff] [review]:
-----------------------------------------------------------------

r=mbrubeck with jimm's requested change

::: browser/metro/base/content/startui/StartUI.js
@@ +110,5 @@
>          aEvent.preventDefault();
>          aEvent.stopPropagation();
>          break;
> +      case "ToolPanelHidden":
> +        // After opening panel UI (console) set disableZoom again.

Weird -- do you know why this was necessary?  (Mostly I'm curious if we need to deal with the same thing elsewhere in our code.)

	Rodrigo Silveira [:rsilveira] [:rodms] Assignee
	Comment 12 • 11 years ago

(In reply to Matt Brubeck (:mbrubeck) from comment #11)
> Comment on attachment 8337171 [details] [diff] [review]
> Patch v1
> 
> Review of attachment 8337171 [details] [diff] [review]:
> -----------------------------------------------------------------
> 
> r=mbrubeck with jimm's requested change
> 
> ::: browser/metro/base/content/startui/StartUI.js
> @@ +110,5 @@
> >          aEvent.preventDefault();
> >          aEvent.stopPropagation();
> >          break;
> > +      case "ToolPanelHidden":
> > +        // After opening panel UI (console) set disableZoom again.
> 
> Weird -- do you know why this was necessary?  (Mostly I'm curious if we need
> to deal with the same thing elsewhere in our code.)

The apzc where the zoom constraints is set is being destroyed when the console's panel completely obstructs it. When the console is hidden, it gets re-generated with the default zoom constraints.

This feels hacky, but I guess we can live with it for the temporary solution. I couldn't find any other instances where zoom is brought back, but it wouldn't surprise me if there are more ways to break this :)

	Rodrigo Silveira [:rsilveira] [:rodms] Assignee
	Comment 13 • 11 years ago

Updated message names. Also added a try/catch around getting the viewId - it was throwing and causing test failures on tests that were too quick.

https://hg.mozilla.org/integration/fx-team/rev/33e652387cd5

	Carsten Book [:Tomcat]
	Comment 14 • 11 years ago

https://hg.mozilla.org/mozilla-central/rev/33e652387cd5