1120452 - Firefox Android: javascript screen.width/.height incorrect on some platforms

Status: RESOLVED DUPLICATE of bug 1594980

(Firefox for Android Graveyard :: Toolbar, defect, P5)

Description

[Johannes Koch]

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:34.0) Gecko/20100101 Firefox/34.0
Build ID: 20141125180439

Steps to reproduce:

1. Hold Android device in portrait orientation.
2. Load http://waldbaer.leute.server.de/display/ with Firefox 34.0
3. Read values for width/height in table screen.
4. Rotate device into landscape orientation.
5. Read values for width/height in table screen.



Actual results:

The screen values are incorrect on the follwing platforms:
Android 4.2.1; Galaxy Nexus: 360x592, 598x360
Android 4.2.2; LG G2: 360x592, 598x360
Android 4.3; Galaxy Nexus: 360x592, 598x360
Android 4.4.2; Nexus 7: 600x904, 960x552
Android 5.0.1; HTC Nexus 9: 768x976, 1024x720

The screen values are correct on the following platforms:
Android 4.4.2; HTC One: 360x640, 640x360
Android 4.4.4; YotaPhone 1: 360x640, 640x360


Expected results:

I would expect the follwing values:
Android 4.2.1; Galaxy Nexus: 360x640, 640x360
Android 4.2.2; LG G2: 360x640, 640x360
Android 4.3; Galaxy Nexus: 360x640, 640x360
Android 4.4.2; Nexus 7: 600x960, 960x600
Android 5.0.1; HTC Nexus 9: 768x1024, 1024x768

Comment 1

[joda17]

I have the same bug on ZTE Open C (Firefox OS 2.1), screen.width|height return 320/533, but real size is 480/800

Comment 2

[Johannes Koch]

(In reply to joda17 from comment #1)
> I have the same bug on ZTE Open C (Firefox OS 2.1), screen.width|height
> return 320/533, but real size is 480/800

I don't think so. What you get with screen.width/.height is measured in viewport pixels. The deviePixelRatio seems to be 1.5.

Comment 3

[Johannes Koch]

I didn't look into the Firefox code, but guess that this issue might be related to using Display.getRealSize() (http://developer.android.com/reference/android/view/Display.html#getRealSize%28android.graphics.Point%29) vs. Display.getSize() (http://developer.android.com/reference/android/view/Display.html#getSize%28android.graphics.Point%29).

Comment 4

[Johannes Koch]

Firefox 47.0, Android 6.0.1, Sony Xperia Z5 Compact
portrait: screen.width: 360; screen.height: 592
landscape: screen.width: 592; screen.height: 360

Chrome 51.0.2704.81, Android 6.0.1, Sony Xperia Z5 Compact
portrait: screen.width: 360; screen.height: 640
landscape: screen.width: 640; screen.height: 360

Both browsers show the same OS chrome (portrait: bars at the top and bottom; landscape: bars at the top and right).

Comment 5

[Kevin Brosnan [Ex-Mozilla]]

This seems to result because Chrome reports the full screen size where as Firefox reports the screen size - the Android navigation bar. On devices where there is a software navigation bar Chrome and Firefox disagree on the size. Without going full screen the Firefox numbers are representative of what the browser actually has to work with as Android reserves the navigation space. 

Thoughts Kats?

Comment 6

[Johannes Koch]

https://drafts.csswg.org/cssom-view/#the-screen-interface:

The width attribute must return the width of the Web-exposed screen area.

with

https://drafts.csswg.org/cssom-view/#web-exposed-screen-area:
The Web-exposed screen area is one of the following:

    The area of the output device, in CSS pixels.

    The area of the viewport, in CSS pixels.

So the spec seams to be intentionally vage :-|

Comment 7

[Kartikaya Gupta (email:[e-mail])]

I think it could be argued that we should change our implementation to match Chrome. That way window.outerWidth/outerHeight would be more meaningful and different from screen.width/height.

Comment 8

[Kevin Brosnan [Ex-Mozilla]]

Yes now that I had a weekend to think about it I realized it was no different than the Windows taskbar or the OS X system menu.

Comment 10

[Firefox Bug Husbandry Bot]

Re-triaging per https://bugzilla.mozilla.org/show_bug.cgi?id=1473195

Needinfo :susheel if you think this bug should be re-triaged.

Comment 11

[Makoto Kato [:m_kato]]

I believe that this is fixed by bug 1594980. If not fixed on Firefox Preview, let me know.