It has been asked in the past, apparently it costs a lot to mobile browsers, so it&#39;s been disabled.

Check [this comment by @PaulIrish](https://twitter.com/paul_irish/status/306818591196602368):

&gt; Fixed-backgrounds have *huge* repaint cost and decimate scrolling performance, which is, I believe, why it was disabled.

you can see workarounds to this in this posts:

https://stackoverflow.com/questions/20443574/fixed-background-image-with-ios7

https://stackoverflow.com/questions/19045364/fixed-body-background-scrolls-with-the-page-on-ios7



It looks to me like the background images aren&#39;t actually background images...the site has the background images and the quotes in sibling divs with the children of the div containing the images having been assigned position: fixed; The quotes div is also given a transparent background. 

    wrapper div{
       image wrapper div{
           div for individual image{ &lt;--- Fixed position
              image &lt;--- relative position
           }
       }
       quote wrapper div{
           div for individual quote{
              quote
           }
       }
     }



I&#39;m using SignalR 2.0 with the .NET client in a mobile application which needs to handle various types of disconnects. Sometimes the SignalR client reconnects automatically - and sometimes it has to be reconnected directly by calling `HubConnection.Start()` again. 

*Since SignalR magically auto-reconnects some of the time, I&#39;m wondering if I&#39;m missing a feature or config setting?*

What&#39;s the best way to set up a client that reconnects automatically? 

---

I&#39;ve seen javascript examples that handle the `Closed()` event and then Connect after a n-seconds. Is there any recommended approach? 

I&#39;ve read the [documentation][1] and several articles about the lifetime of SignalR connections, but I&#39;m still unclear on how to handle the client reconnect.


  [1]: http://www.asp.net/signalr/overview/signalr-20/hubs-api/hubs-api-guide-net-client

Best practice for reconnecting SignalR 2.0 .NET client to server hub

More than any other language I know, I&#39;ve &quot;learned&quot; Bash by Googling every time I need some little thing. Consequently, I can patchwork together little scripts that appear to work. However, I don&#39;t *really* know what&#39;s going on, and I was hoping for a more formal introduction to Bash as a programming language. For example: What is the evaluation order? what are the scoping rules? What is the typing discipline, e.g. is everything a string? What is the state of the program -- is it a key-value assignment of strings to variable names; is there more than that, e.g. the stack? Is there a heap? And so on.

I thought to consult [the GNU Bash manual](www.gnu.org/software/bash/manual/bashref.html) for this kind of insight, but it doesn&#39;t seem to be what I want; it&#39;s more of a laundry list of syntactic sugar rather than an explanation of the core semantic model. The million-and-one &quot;bash tutorials&quot; online are only worse. Perhaps I should first study `sh`, and understand Bash as a syntactic sugar on top of this? I don&#39;t know if this is an accurate model, though.

Any suggestions?

**EDIT:** I&#39;ve been asked to provide examples of what ideally I&#39;m looking for. A rather extreme example of what I would consider a &quot;formal semantics&quot; is [this paper on &quot;the essence of JavaScript&quot;](http://cs.brown.edu/~sk/Publications/Papers/Published/gsk-essence-javascript/paper.pdf). Perhaps a slightly less formal example is the [Haskell 2010 report](http://www.haskell.org/definition/haskell2010.pdf).

A semantics for Bash scripts?

I&#39;m trying to get fixed-background-image divs working on iOS for a school project. I&#39;ve been using

    background-attachment: fixed;

But this is leading to weird sizing and no scrolling effects in mobile safari. [Here is the site](http://qrohlf.com/hplus/) that I&#39;m working with; the method I&#39;m currently using for the quote div image backgrounds works well on desktops but fails completely on iOS.


Somehow, http://www.everyonedeservesgreatdesign.com got this working. I&#39;m having difficulty following the code because they&#39;re using a squarespace template of some kind, but it looks like they&#39;re putting images into a `position:fixed` div that is somehow being clipped by its `position:relative` parent div. I was under the impression that it wasn&#39;t possible to clip `position:fixed` divs with anything other than the viewport, so I&#39;m very curious as to what&#39;s going on here. 

Any ideas on how to implement this method for fixed image div backgrounds in my site?

How to replicate background-attachment fixed on iOS

I'm trying to get fixed-background-image divs working on iOS for a school project. I've been using
<pre><code class="hljs language-css">background-attachment: fixed;
</code></pre>
But this is leading to weird sizing and no scrolling effects in mobile safari. <a href="http://qrohlf.com/hplus/" target="_blank" rel="noopener noreferrer">Here is the site</a> that I'm working with; the method I'm currently using for the quote div image backgrounds works well on desktops but fails completely on iOS.
Somehow, <a href="http://www.everyonedeservesgreatdesign.com" target="_blank" rel="noopener noreferrer">http://www.everyonedeservesgreatdesign.com</a> got this working. I'm having difficulty following the code because they're using a squarespace template of some kind, but it looks like they're putting images into a <code>position:fixed</code> div that is somehow being clipped by its <code>position:relative</code> parent div. I was under the impression that it wasn't possible to clip <code>position:fixed</code> divs with anything other than the viewport, so I'm very curious as to what's going on here.
Any ideas on how to implement this method for fixed image div backgrounds in my site?

I can not launch my java application as a web applet in HTML (I am using HTML 4.01, I know it doesn&#39;t work in html5). The error message it returns is:

&gt; java : Unsupported major.minor version 52.0

I have tried downgrading my java JRE/JDK/SDK but I still get the same error message. The current version of java I am now using is 1.8.0_05.

Java unsupported major minor version 52.0

I have a web page made by html+javascript which is demo, I want to know how to read a local csv file and read line by line so that I can extract data from the csv file.

How to use Javascript to read local text file and read line by line?

I have a website of which I want to copy an HTML code from - **how do I copy all the text in inspect element** - so I don&#39;t get the website&#39;s HTML code, but the code that I have already changed so that I don&#39;t have elements I don&#39;t want in my own webpage?

Copying HTML code in Google Chrome&#39;s inspect element

I was finding solution to print webpage into local file PDF, using Python. one of the good solution is to use Qt, found here, https://bharatikunal.wordpress.com/2010/01/.

It didn&#39;t work at the beginning as I had problem with the installation of PyQt4 because it gave error messages such as &#39;`ImportError: No module named PyQt4.QtCore`&#39;, and &#39;`ImportError: No module named PyQt4.QtCore`&#39;.

It was because PyQt4&#39;s not installed properly. 
I used to have the libraries located at C:\Python27\Lib however it&#39;s not for PyQt4. 

In fact, it simply needs to download from http://www.riverbankcomputing.com/software/pyqt/download (mind the correct Python version you are using), and install it to C:\Python27 (my case). That&#39;s it.

Now the scripts runs fine so I want to share it. for more options in using Qprinter, please refer to http://qt-project.org/doc/qt-4.8/qprinter.html#Orientation-enum.


How to convert webpage into PDF by using Python

I need to fill the **remaining vertical space** of `#wrapper` under `#first` with `#second` div.

I need an only CSS solution.

&lt;!-- begin snippet: js hide: false console: true babel: false --&gt;

&lt;!-- language: lang-css --&gt;

    #wrapper {
      width: 300px;
      height: 100%;
    }

    #first {
      width: 300px;
      height: 200px;
      background-color: #F5DEB3;
    }

    #second {
      width: 300px;
      height: 100%;
      background-color: #9ACD32;
    }

&lt;!-- language: lang-html --&gt;

    &lt;div id=&quot;wrapper&quot;&gt;
      &lt;div id=&quot;first&quot;&gt;&lt;/div&gt;
      &lt;div id=&quot;second&quot;&gt;&lt;/div&gt;
    &lt;/div&gt;

&lt;!-- end snippet --&gt;



Fill remaining vertical space - only CSS

I am trying to take a screenshot of an `AVPlayer` inside a bigger view. I want to build a testing framework only, so private `APIs` or any method is good, because the framework will not be included when releasing to the AppStore. 

I have tried with using 

 - `UIGetScreenImage()` : works well on simulator but not on device  
 - `snapshotviewafterscreenupdates`: it shows the view but I cannot create a `UIImage` from that.
 - `drawViewInHierarchy` and `renderInContext` will not work with `AVPlayer`   
 - I don&#39;t want to use `AVAssetGenerator` for getting image from video, it is hard to get a good coordinate or the video player as the subview of other views

Screenshot for AVPlayer and Video

My layout constraints are fine in Interface Builder but an exception occurs at runtime thanks to some part of the framework applying fixed height and width constraints that I really don&#39;t want. Why are they there, and how to turn them off?

They&#39;re the last two constraints shown in the logged list:

    2014-04-26 09:02:58.687 BBCNews[32058:60b] Unable to simultaneously satisfy constraints.
    	Probably at least one of the constraints in the following list is one you don&#39;t want. Try this: (1) look at each constraint and try to figure out which you don&#39;t expect; (2) find the code that added the unwanted constraint or constraints and fix it. (Note: If you&#39;re seeing NSAutoresizingMaskLayoutConstraints that you don&#39;t understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
    (
        &quot;&lt;NSLayoutConstraint:0xbf478a0 UIView:0xbf4a3c0.height == 0.28125*UIView:0xbf4a3c0.width&gt;&quot;,
        &quot;&lt;NSLayoutConstraint:0xbf47190 UIView:0xbf4a3c0.leading == BNMyNewsCell_landscape:0xbf48b10.leading&gt;&quot;,
        &quot;&lt;NSLayoutConstraint:0xbf47160 UIView:0xbf4a3c0.trailing == BNMyNewsCell_landscape:0xbf48b10.trailing&gt;&quot;,
        &quot;&lt;NSLayoutConstraint:0xbf47130 BNMyNewsCell_landscape:0xbf48b10.bottom == UIView:0xbf4a3c0.bottom&gt;&quot;,
        &quot;&lt;NSLayoutConstraint:0xbf47100 UIView:0xbf4a3c0.top == BNMyNewsCell_landscape:0xbf48b10.top&gt;&quot;,
        &quot;&lt;NSLayoutConstraint:0xd4c3c40 &#39;UIView-Encapsulated-Layout-Width&#39; H:[BNMyNewsCell_landscape:0xbf48b10(304)]&gt;&quot;,
        &quot;&lt;NSLayoutConstraint:0xd4c38a0 &#39;UIView-Encapsulated-Layout-Height&#39; V:[BNMyNewsCell_landscape:0xbf48b10(290)]&gt;&quot;
    }
    Will attempt to recover by breaking constraint 
    
    &lt;NSLayoutConstraint:0xbf478a0 UIView:0xbf4a3c0.height == 0.28125*UIView:0xbf4a3c0.width&gt;




Auto-layout: What creates constraints named UIView-Encapsulated-Layout-Width &amp; Height?

Is it possible to change the corner radius of UISegmentedControl? I have tried the following approach which we use to change a UIView&#39;s corner radius.
 

    self.segmentedControl.layer.cornerRadius = 15.0;
    self.segmentedControl.layer.masksToBounds = YES;

This did not work as you can see it only cuts off the UISegmentedControl&#39;s corner:

 ![cut off corner][1]


  [1]: http://i.stack.imgur.com/VHc2V.png

How to change the corner radius of UISegmentedControl?

I am creating a tab bar iOS app. The tab bar view controller has two tabs, each of them connected to a view controller.

This how it looks:

![enter image description here][1]

I need to add more tabs to the tab controller. I am doing it at the storyboard as follows:

1. I add a new view controller.
2. I control-drag from the tab bar controller to the new created view controller.
3. A window opens and I select Relationship Segue-View Controller.
4. The segue from the tab bar controller to the new view controller is created.

I think that is the way to do it, but after that the tab bar controller doesn&#39;t show any tab icons, the tab bar becomes grey.

Like this:

![enter image description here][2]


I need to know what am I doing wrong. 

 [1]: http://i.stack.imgur.com/prmDk.png
  [2]: http://i.stack.imgur.com/eOOz4.png

Adding new tabs to a tab bar controller

I looked into using `tgmath.h` to deal with the `CGFloat typedef float/double` mess when dealing with arm64.

[This answer](https://stackoverflow.com/questions/22267237/what-do-i-need-to-do-to-use-tgmath-on-ios) has a pretty good description of how to use it, except that it didn&#39;t work at all for me. No matter what, my code was still calling the `math.h` functions.

After spending some time looking at all of the project compiler settings, I found that disabling the &quot;Modules&quot; feature (https://stackoverflow.com/questions/18947516/import-vs-import-ios-7) makes it all work. More specifically, the option in the project settings is called `Enable Modules(C and Objective-C)` in the `Apple LLVM 5.1 - Language - Modules` dropdown.

To see a quick example of this issue, download a project that uses tgmath, [such as MBProgressHUD](https://github.com/jdg/MBProgressHUD), and see what happens when you enable the modules project setting. The `tgmath.h` calls get replaced with regular `math.h` calls.

My question is:

1. Why do modules prevent tgmath from being imported properly?

2. Is there a way to get around it and use both tgmath and modules? I would like to still be able to use them.

tgmath.h doesn&#39;t work if modules are enabled

I have a `&lt;ul&gt;` that is a flex-box and a bunch of `&lt;li&gt;`s in it which are the flex-items.

I am trying to get the `&lt;li&gt;` to have a flexible width, that stays between two sizes using min-width and max-width. It works great as long as they are on the same line. However, when they wrap, the `&lt;li&gt;` s on the new line use as much space as they can. Which means they are small on the first line, and big on the second line when there are just a few of them.

Is there a way to tell flexbox to keep the items the width after wrapping, while keeping the flexible width?


**wrapping demo:**

![enter image description here][1]


My code looks like this:

&lt;!-- language: lang-html --&gt;

    &lt;ul&gt;
      &lt;li&gt;
        &lt;figure&gt;
          &lt;img src=&quot;http://placekitten.com/g/250/250&quot;&gt;
        &lt;/figure&gt;
      &lt;/li&gt;
      &lt;li&gt;
        &lt;figure&gt;
          &lt;img src=&quot;http://placekitten.com/g/100/100&quot;&gt;
        &lt;/figure&gt;
      &lt;/li&gt;
      &lt;!-- ... --&gt;
    &lt;/ul&gt;

And the CSS:

&lt;!-- language: lang-sass --&gt;

    ul {
      display: flex;
      flex-wrap: wrap;
    }

      li {
        min-width: 40px;
        max-width: 100px;
        flex: 1 0 0;
      }
**[Here&#39;s a live example on codepen with some extra comments](http://codepen.io/midu/pen/gahFu)**, resize your window to see it wrap.


  [1]: http://i.stack.imgur.com/y2WfL.gif

How to keep wrapped flex-items the same width as the elements on the previous row?

I added this but still the blue outline appear when the button is clicked.

    .btn:focus {
      outline: none;
    }

how to remove that ugly thingy?

bootstrap button shows blue outline when clicked

Say you have this:

    html, body {margin: 0; padding: 0}
    .box {width: 100vw; height: 100vh}

    &lt;div class=&quot;box&quot;&gt;Screen 1&lt;/div&gt;

You&#39;ll get something that fills the screen, no scrollbars. But add another:

    &lt;div class=&quot;box&quot;&gt;Screen 1&lt;/div&gt;
    &lt;div class=&quot;box&quot;&gt;Screen 2&lt;/div&gt;

You get not only vertical scrollbars (expected), but a slight horizontal scroll.

I realize you could omit the width, or set it to width: 100%, but I&#39;m curious why this is happening. Isn&#39;t 100vw supposed to be &quot;100% of the viewport width&quot;?

100vw causing horizontal overflow, but only if more than one?

**What should I use between bootstrap.min.css or bootstrap.css?**

I am confused between the two files because `bootstrap.css` is readable i.e. scrollable up &amp; down. But the `bootstrap.min.css` is hard to edit since you can only scroll it left and right.

What is the difference between bootstrap.min.css and bootstrap.css?

On Firefox 28, I&#39;m using `&lt;input type=&quot;number&quot;&gt;` works great because it brings up the numerical keyboard on input fields which should only contain numbers.

In Firefox 29, using number inputs displays spin buttons at the right side of the field, which looks like crap in my design. I really don&#39;t need the buttons, because they are useless when you need to write something like a 6~10 digit number anyway.

Is it possible to disable this with CSS or jQuery?

Content Type	Original Author	Original Content on Stackoverflow
Question	QRohlf	View Question on Stackoverflow
Solution 1 - Html	fernandopasik	View Answer on Stackoverflow
Solution 2 - Html	unconditional_loading	View Answer on Stackoverflow

How to replicate background-attachment fixed on iOS

Html Problem Overview

Html Solutions

Solution 1 - Html

Solution 2 - Html

A semantics for Bash scripts?

Best practice for reconnecting SignalR 2.0 .NET client to server hub

Attributions