Mobile orientation change not applying CSS

问题:

I'm testing a website I'm developing and am using media queries.

When I test and resize the page in a browser, everything is good.

But when I test on my mobile device, I encounter a problem when I change the orientation of the phone.

If I load the page in landscape mode, the correct CSS are applied.

When I change to portrait, the CSS are also correct.

But if I go back to landscape, the portrait css classes are still being applied.

I'm using these metatags

<meta name="MobileOptimized" content="320">
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no">

And in my media queries I have

@media 
only screen and (max-width: 610px),
only screen and (max-width: 610px) and (orientation:landscape) { ... }

@media
only screen and (min-device-width: 240px) and (max-device-width: 520px),
only screen and (min-width: 240px) and (max-width: 520px) { ... } 

I've alerted the device width to make sure it's ok and in landscape mode it's 598px wide and portrait is 384px

I'm using a Nexus 4 (Android 4.3)

How come the CSS aren't applied once I change back the orientation?

EDIT: If I load the site in portrait and then change to landscape, the CSS aren't applied. It's as if once it goes to the smallest resolution, it can't go back.

回答1:

On my Nexus 4, I have something that looks like this and seems to work for your test cases:

<meta http-equiv='X-UA-Compatible' content='IE=edge,chrome=1'>
<meta name='viewport' content='width=device-width'>

And I make no reference to orientation in the media query, for example:

@media only screen and (max-width: 610px) { /* Some CSS here */ }

EDIT: Looks like you have to put max-device-width after the other max-width stuff in terms of the media queries. To quote vyx.ca in the comments below...

Just found my problem. Notice how I define 'max-device-width' before the rest. If I put that condition last, it works. 'max-device-width' is used for retina display.

回答2:

My problem is related to the order of my CSS requests.

I used to define 'min-device-width' before the rest.

@media
only screen and (min-device-width: 240px) and (max-device-width: 520px),
only screen and (min-width: 240px) and (max-width: 520px) { ... } 

But if I define it last, it works.

@media
   only screen and (min-width: 240px) and (max-width: 520px),
   only screen and (min-device-width: 240px) and (max-device-width: 520px) { ... }

For more information about device-width:- check out this question

回答3:

this code worked for me:-

  @media only screen and (min-width: 240px) and (max-width: 520px), only screen and (min-device-width: 240px) and (max-device-width: 520px) and (orientation:portrait)
{
    body
    {
        background:#009;
    }
}

@media only screen and and (max-width: 610px), only screen and (max-device-width: 610px) and (orientation:landscape)
{
    body
    {
        background:#993;
    }
}

回答4:

Your media queries have overlap. Max-width of 520 will also be true of max-width 610. Also you have an OR in the landscape so it's possible to be true in Portrait if max-width 610 is true. Overlapping media queries will work like CSS in that it cascades so you'll get odd behavior.

I don't see any reference to orientation:portrait in your queries so how do you know portrait classes are being applied. You typically want to make it an either or when doing orientation queries.

Also try adding min-width to remove any width overlap

@media only screen and (orientation:landscape) { ... }

@media only screen and (orientation:portrait) { ... }

回答5:

Well-known quiksmode site defines device-width / device-height media features as static.

These media queries are static once determined; i.e. they do not update the value they’re checked against when the device orientation is changed. (So if you start in portrait and then switch to landscape, the portrait device-width still counts. Reloading the page solves this.)

That's why using max-device-width is still applied after changing orientation.