I'm trying to make a window based application for web browsers. The number of windows is considerably high, so I'm storing them as HTML files (one per window) that I asynchronously retrieve from the server according to user interaction.
To add a window to the main page, I first add the link elements (CSS) of the downloaded document to its head section, and then I append the content of the body section to a certain div. When a window is closed, I just remove these elements.
This approach seems to be working nicely, but I can see that sometimes when I add a window, its elements are visible out of position with no style, and after a brief moment they are correctly painted.
I don't have a strong background in web programming, but I suspect this might be related to what it is called "browser reflow". Does it mean that it is taking too much time to repaint everything? Is it possible to just hide these "unstyled" elements until it is safe to show them?
Any guidance would be appreciated.
Some time away from the computer seems to have relaxed my mind. I was erroneously assuming that adding new link elements to the head section would load the CSS files immediately. Obviously, the browser needs to retrieve them from the server first. So, the DOM elements I'm adding don't show their style because the CSS files have not been downloaded yet. I think this is the right answer.
Related
I am trying to use the built in inspector tool in Google Chrome to manipulate the site http://www.di.se (as it probably has one of the most # layouts I have ever seen on a popular website) with around 300 000 visitors daily.
It seems to be mainly built with three HTML frame tags with the names: historyFrame, headerFrame and contentFrame. I can remove the headerFrame that covers a huge part of the view. However, I don't know how to change the contentFrame size so that it will cover the entire screen.
I have tried to add a CSS height property but it does not seem to change anything. If this is solvable I would be very thankful and so would 300000 other users :) Thanks!
The frameset, which is the parent of the frame you removed, specifies the heights for each of the frames, currently rows="0,210,*". So if you remove the header frame, the content frame becomes the second frame and gets a height of 210. By changing this attribute to 0,* the problem should be fixed.
However I'm not able to modify this property in Chrome's toolkit. Maybe this is a limitation of the developer tools of Chrome. After all, frames are old (removed even from HTML5), so maybe they didn't pay much attention to supporting it.
Note though that the top frame contains the advertising that probably pays for the site. If you got this working and all 300.000 users would use your solution, then the site would probably seize to exist, and you got 300.000 unhappy users. So think twice before you do this.
You can do it by:
First deleting the first Frame(header)
and modify this:
from:
rows=".260,*"
To:
rows="1,*"
So you have only the frame you want, no useless data and the frame you want take 100% of the screen.
I am new to CSS/HTML and couldn't find the answer to this question probably because I'm not using the proper terminology.
I have my separate pages set-up and don't know how to keep the 'user-zoom' consistent among my pages.
For example:
-User is on home.html. User zooms 3 times (control + '+'). Font is much bigger.
-User navigates to about.html. Font and layout is back to the small, default size.
Is there a CSS/HTML/Javascript attribute to keep the pages consistent? Thanks a lot!
Edit: For newer HTML coders, it appears that when you run the code on your local machine clicking on a link to another page will "reset" all the zoom [IE and Chrome tested]. However, apparently when you run it from a server the browser will remember the specific zoom and you don't have to worry about it. Hope this helps at least one person!
Because the zoom level is controlled by the browser itself, the way it behaves on a per page basis cannot be adjusted using CSS/HTML/JS.
A workaround would be to create custom zoom buttons with JS and the CSS transform property. You would then want to save the zoom level to a cookie and apply the current saved zoom level to each page the user loads.
Is it possible to print a HTML page with truly absolute positioned elements to paper? It seems all browsers are doing a big mess here. It is easy to define a body by absolute units (eg. cm) and place elements by position: absolute inside. However, every browser seem to try to make it impossible to print such a page. FF for example is adding print margins, even when printing to a PDF on linux despite 0-margin page settings. Chrome seems to shrink the page in every case.
So how to print something with absolute positioning, eg. paper form fields, markings etc.?
Have I overlooked something?
Sadly, the CSS3 Module: Paged Media allows all this to happen. This are the rules concerning pages which are too big:
3.3.3. Rendering page boxes that do not fit a page sheet
If a page box does not match the target page sheet dimensions, the user agent MAY choose (in order of preference) to:
Render the page box at the indicated size on a larger page sheet.
Rotate the page box 90° if this will make the page box fit the page sheet.
Scale the page box to fit the page sheet. (There is no requirement to maintain the aspect ratio of the page or of any elements on the page when scaling; however, preservation of the aspect ratio is preferred.) [done by Chrome]
Reformat the page contents, including 'spilling' onto other page sheets. [done by many other or older browsers]
Clip overflowed content (least preferred).
The user agent should consult the user before performing these operations.
3.3.4. Positioning the page box on the sheet
When the page box is smaller than the page size, the user agent should center the page box on the sheet since this will align double-sided pages and avoid accidental loss of information that is printed near the edge of the sheet.
And this is the rule which breaks all your positioned stuff:
3.7. Content outside the page box
[...] Also, when boxes are positioned absolutely, they MAY end up
in "inconvenient" locations. For example, images MAY be placed on the
edge of the page box. Similarly when boxes use fixed or relative
positioning, they MAY also end up outside of the page box.
A specification for the exact formatting of such elements lies outside
the scope of this document. However, we recommend that authors and
user agents observe the following general principles concerning
content outside the page box:
User agents SHOULD avoid generating a large number of empty page boxes to honor the positioning of elements (e.g., you don't want to
print 100 blank pages). Note, however, that generating a small number
of empty page boxes MAY be necessary to honor the 'left' and 'right'
values for 'page-break-before' and 'page-break-after'.
Authors SHOULD not position elements in inconvenient locations just to avoid rendering them. Instead:
To suppress box generation entirely, set the 'display' property to 'none'.
To make a box invisible, set the 'visibility' property.
User agents MAY handle boxes positioned outside the page box in several ways, including discarding them or creating page boxes for
them at the end of the document.
Have a look at the second paragraph of section 3.7: A specification for the exact formatting of such elements lies outside the scope of this document. Since there is no other document and no other guideline then the general principle following this paragraph, every browser can do whatever it want.
It's one of the flaws that are currently in this CSS3 module. However, I think those flaws cannot be removed by a CSS4 or revised CSS3 module, as the variety of possible stylesheets and resulting layouts is too huge too cover. Also note a little footnote given in CSS Print Profile:
‡ The printer MAY ignore positioned elements that are placed on the page before the position of the current element in the normal flow.
So it's basically not possible to create the same effect in every browser. As for the time being, the only possible way to achieve a portable document is to create a PDF with a third-party application or via a PDF printer and your most favorite browser. Every other way is bound to fail as long as either the W3C's recommendations aren't strict or the browser vendors implement whatever they want.
See also:
CSS3 Module: Paged Media (Working draft, last revision 2006)
CSS Print Profile (Working draft, last revision 2006)
Additional notes
If you have a bunch of position:absolute elements which need to be printed it's sometimes a good question whether an element actually needs to be positioned absolute, or if the same effect can be achieved in a slightly different or easier way. Also note that you should use display:none on each element that isn't truly needed for the printed media, such as ads, navigations, etc...
As you say, web browsers tend to do crazy things when printing. Print-oriented engines are often better.
WeasyPrint is an open-source engine that renders to PDF and supports absolute positioning as well as CSS 3 Paged Media to set the page margins:
#page { margin: 1cm /* or 0, if you want */ }
Make your container to have relative position. That's the only way to keep absolute positioned elements in the same place at every screen and paper. so if your main div (the div where all of your content is located) add following to your css:
#maindivname{position:relative;}
Should do the trick.
I have tested browser status for printing "position:absolute" elements with the following results:
IE 11: Fail. Doesn't matter what OS, 7,8,8.1.
IE 10: Pass. However, you cannot revert to 10 on 8.1 so folks with that are stuck.
Firefox up to 38.05 = Fail. Unknown if any version ever worked.
The good news is that it looks like the Blink/WebKit people did their homework instead of using poor code.
Chrome: Pass
Opera: Pass
Media Queries will do the trick -- check this link and previous question out, maybe it will help.
Suggestions for debugging print stylesheets?
Media Query transitioning px into inches/cm/whatever needed for printing requirements.
That border/margin you mentioned is probably your printer's printable area (the grip edge). Most printers need some type of edge to grab and feed the stock. That's why when one prints a full-bleed document (ink to the very edge), it's printed on stock larger than needed, then trimmed down.
set the margin with page setup is the first and primary solutions for printing the HTML page or a DIV .
After all not expected result will come then you need some digs on your HTML page.
Make a window without title bar or any custom bar using java script.And put all Original data into that window with a position:relative and also set the media type as print.
position:relative;
media:print;
Hope it will helpful.
Use in CSS this property:
body{
-webkit-print-color-adjust:exact;
}
This help positions absolutes and backgrounds in tables.
I'm using the excellent BeautyTips plugin as a means of indicating validation failures to end users and I'm running into positioning problems whenever page content is dynamically added, removed, or animated.
Here's a concrete example. I have a DIV at the top of each page that’s used for confirmation/error messages. It's displayed in $(document.ready) using slideToggle(). This naturally "pushes" all subsequent html content down, throwing off the positioning/alignment of the beautytips. If I call the plug-in's built-in refresh method after slideToggle() has fired, said positioning problems are corrected. You can see the before/after screen-shots here and here.
One possible workaround would be to programmatically detect DOM changes, specifically changes to css, so that I could then loop over each beautytip and manually reload it. However, it appears that there are no native jQuery events which expose such functionality. I've seen the impressive jQuery plug-in by Rick Strahl that monitors CSS changes, but it seems based on the assumption that one knows ahead of time the specific HTML element(s) they wish to monitor. I want to monitor the entire document, since I can't be expected to know what html elements might exist on a given page that a) are going to be animated and b) would be at such a position in the document that they would "push" down the my beautytips. And I certainly don't want to have to incur the massive performance penalty of polling every block level element in the document.
I should mention that the plug-in works perfectly if I use it in its default "hover" mode in which beautytips are displayed only in response to user mouse input. Unfortunately, there is a design constraint imposed on the application that states all validation errors must be displayed after form submission without additional user interaction.
I'm sure there's a really simple/elegant fix that is completely eluding me. I could avoid all of this hassle, of course, by simply not using animation to display page content, but that seems like a high price to pay.
Is it possible to use CSS to work like frames?
What I mean is, when we use frames (left, right for example), clicking on left will refresh only the right section using the 'target' attribute.
Is it possible to create this effect with CSS?
Thanks.
Using frames is usually a bad idea
To answer your question, no, CSS cannot be used to work like frames. CSS is used to changing the style of HTML and as such, cannot actually change the content of a page. It can be used to hide content, but I don't think that is what you require.
However, I feel in this case you may be asking the wrong question. As frames are usually the wrong approach.
When starting out in web design, frames seem like a great idea. You can seperate your navigation from your content, your site will load quicker because the navigation is not loaded every time and the menu is always visible, even when the page is loading.
But, actually, frames are incredibly bad for your usability.
Your users cannot bookmark individual pages
Printing is broken
Standard features in a browser like open in new tab often breaks
Users cannot copy/paste the web address for a specific page for sending to a friend
Frames do have their uses (e.g. Google image search), but for standard navigation menus they are not recommended. Try creating a page in a dynamic server language such as PHP or ASP.NET.
These languages have ways of creating standard elements such as your navigation menu without the use of frames.
No, this has nothing to do with CSS. CSS is for styling elements only. What you are looking for is an IFRAME. And IFRAME can be given a name
<iframe name="my_iframe" src="xyz.htm"></ifram>
and then be targeted in a link.
I've got a design that relies on framed content using CSS. You can do this by using overflow:auto, however it won't do what you want, i.e. loading certain portions of a page. To do this you'd need to use some AJAX library such as jQuery to load the content area dynamically. This is quite dangerous though as your URL may not relate to the current content of the page.
You could probably do something with the overflow part of CSS.
If you set up a div with overflow:auto with a fixed width and height with alot of content you will get scrollbars. Potentially you could use anchors to get content to move to be viewed within the div.
This means that all your content is in one page and it is just moved around with the anchors. You could do a similar thing using a jquery tabs plugin too.
I have never tried this and it might need javascript to get it to work fully.