Polymer core-pages no height - html

I'm trying to create my first project with Polymer. I use core-pages to navigate between different pages. These pages should have a white background-color in css, but there is no on the site.
Here is a link: http://www.test.gruppenstunde.eu/
The problem is, that core-pages and my custom element modules-list don't have a fixed height, because that changes with the content. What do I have to change?

Currently, your <modules-list> is styled with position: absolute. Switching to position: relative should accomplish what you're looking for—the white background color will show up. Below is an example of the change made via Chrome's DevTools, illustrating what it will look like:
I've found myself needing to brush up on CSS positioning quite a bit in order to work effectively with Polymer, since there are a number of <core-*> elements that effectively don't have any default positioning/sizing info, requiring developers to make the appropriate decisions for their apps. I've found this guide particularly useful, but there are plenty of other good resources out there.

This works when using vanilla core-pages and children with class="core-selected"
core-pages .core-selected {
position: relative;
display: block;
}
Found more help here: https://groups.google.com/forum/#!topic/polymer-dev/HrsXUjni2kA

Related

how to make the menu bar that changes color as it goes down in html

In this website "https://www.armoli.com" as you can see, the menu is transparent at first and integrated with the image on the back, but its color changes as you scroll down.how can I do this in html?(with css and js)
I think You will have to use Intersection Observer API.
https://developer.mozilla.org/en-US/docs/Web/API/Intersection_Observer_API
Much better than listening to scroll event.
(it is an API that helps you listen to an element in the DOM (can be an array). and it triggers when that element appears on the screen. then you manipulate the DOM depending on what appears there.
Check this tutorial: https://www.youtube.com/watch?v=T8EYosX4NOo
You can probabbly do this using css and javascript, simply make two css classes with your different themes e.g.
.navbar_active {
color: red;
}
.navbar_other {
color: blue;
}
Then just use some javascript to add/remove the css classes, depending on the current scroll.
Edit: something like this sounds like what your looking for: Transitioning Affixed Navigation bar - CSS theres, even a fiddle you can try: http://jsfiddle.net/jv0qvvp2/1
basically the same approach as what i said, add/remove css classes depending on the current scroll position

Which css style has least effect on an element?

Today I was trying to create a dummy css rule for testing and investigation.
.dummy {
some-style : somevalue;
}
Ideally the class should have no visible effect. I want to be able to apply the class to elements but cause the least visible effect possible on any elements it is applied to. For example
<div class="dummy"> should look and behaves as much as possible like <div>
I did not want the class to be empty. Can anyone suggest a style that I could add to the class that would have the least visible impact when applied to a general html element? I can't think of anything completely harmless.
UPDATE: I wanted to add the style to some existing html. The reason was to use the style as a marker for diagnostic purposes. It would help me see when and where styles and stylesheets were getting loaded/cached and where and why some styles were getting overridden, sometimes by the browser defaults which seemed odd. At the time I didn't have exclusive use of the system I was working on so I wanted something that was going to be invisible to other users but I could see in Developer Tools.
UPDATE 2 : the html/css wasn't written by me and I didn't have my own environment in which to work. I was trying to investigate some problems in-situ in someone else's system. I had tried using DevTools in the browser but wasn't getting anywhere with that. I wanted to be able to make some small changes to their html/css to aid my diagnostics. I didn't want them to have any obvious effect on the system for other people (except in DevTools, viewed by me).
It was a Wordpress site and they only had two environments, one for live and one for testing. I was working with the test system. There were other people testing at the time, though mainly checking content.
The real thorny problem was why was the font-size in the calendar widget much larger than everything else on the site? Inspecting using DevTools I could see the font-size style was getting overridden by the browser default style when it seemed to me there were other css selectors that should have taken precedence. It looked bizarre. In the end it turned out to be a missing !DOCTYPE tag in the html. So nothing to do with the css itself.
I didn't like this way of working, fiddling in someone's system, but there wasn't much else to do and it did help to resolve the problem for them.
Hopefully I don't have to do this again, but ever since I have been wondering what was the most harmless style that I could have used?
I thought I would ask here as there must be people who know CSS better than me.
You can use this:
.dummy{
min-width: 0;
min-height: 0;
}
If you just need anything beeing set you could assign rules that are default anyway. For block elements like div set
.block-class { display: block; }
And for inline elements like span
.inline-class { display: inline; }
Of course it could be an issue doing so in some rare cases but in general it's quite harmless I guess.
In principle, for any property you can have an arrangement like this:
div {
some-style : a-valid-value-for-some-style;
}
.dummy {
some-style : a-different-valid-value-for-some-style;
}
And .dummy's style will have an effect, no matter what some-style is.
Your best bet is to make use of CSS variables. These are custom properties and start with a double hyphen. so
.dummy {
--dummy-style: foo;
}
will make --dummy-style a property with value "foo". So long as you don't employ the variable as the value in another property, it will have no visible effect.

Pushing down the body and background universally

So, there have been some questions about this already, but mine is a bit more specific.
I want to add a 40px high admin bar to the top of all pages of my CMS when the user is logged in as an admin.
But I don't want to obscure the content on the page, so I want to push it down. Remember, this is a CMS so there is a lot of different CSS/designs on all the pages that use it. The system do have control of all the CSS though, so I can change it on the fly.
I started out by adding a "margin-top: 40px" to the body element before realizing that the background-image of BODY isn't actually attached to the body, but rather the otherwise unstylable root element.
So, I used "background-position: 0 40px" to move down the background image. Score! Only, some sites already used background-position to position their background in relation to the content and me overriding that severely messed up the design of those pages.
So - is there a better way to handle this? Or am I going to have to parse and alter every sites possible background-position on the fly - which I can do, but rather not :)
Thanks for your help!
To avoid the problem, you could change the way your CMS functions. Add a full page wrapper div that acts as a body for the user's content. Then, inserting a 40px high element above the wrapper will universally push it down.
You can try the following, you might need to position your cms toolbar negatively though.
html { margin-top: 40px; }
#yourCmsBar { position: absolute; top: -40px; height: 40px; }
You can push down the html element if the background is applied to the html element, and then use position:absolute to positioning your header. Example: http://jsfiddle.net/u22zE/2/

Resizable frame emulation

I understand that <frameset> and <frame> tag are becoming deprecated. Is there a way to emulate resizable frames? What I want is a narrow separator separating the area either horizontally or vertically, which is movable by the user so that when one side of it becomes smaller, the other side becomes larger, and vice versa. I do not want to fill in each frame with an html page like the conventional frame, but instead with some DOM materials.
I know that CSS3 has resize attribute, but that controls only the size of itself. I am not sure if this is to be used for the solution.
I don't particularly prefer using JavaScript, but I am not excluding the possibility of using it if necessary.
Do not use frameset, please. I don't think jQuery resize will help you much, either.
The best way to do this is by using a "splitter". There are several plugins for jquery that will do this in many different way and they all are actually quite simple.
I have previously used this one: http://methvin.com/splitter/
You can find a nice demo here: http://methvin.com/splitter/3psplitter.html
From my point of view jQuery Resizable or such js things is your solution. Go for it's demos.
In case of using jQuery you'll have extra possibilities:
Maximum / minimum size
Constrain resize area
Delay start
Snap to grid
Here is a sample code for jQuery Resizable default functionality:
<style>
#resizable {
width: 150px;
height: 150px;
display: block;
border: 1px solid gray;
text-align: center;
}
</style>
<script>
$(function() {
$("#resizable").resizable();
});
</script>
<div id="resizable">
<h3>Resizable</h3>
</div>
You may like this link for YUI
http://people.ischool.berkeley.edu/~rdhyee/yui/examples/layout/panel_layout.html
Example:
http://people.ischool.berkeley.edu/~rdhyee/yui/examples/layout/panel_layout_source.html
Janus Troelsen's solution above is great if you don't mind tables.
I also found this solution by SoonDead without tables, which worked great with Chrome and FF, but had to spend a nasty amount of time for IE8. It's on StackOverflow as "Emulate Frameset Separator Behavior"
I would look into Javascript and drag and drop support.
In fact, an emulated frameset could be just two divs and a handle between them which can be grabbed to resize. JQuery has samples to demonstrate how to resize an element: http://jqueryui.com/demos/resizable/ I don't think it would be very difficult to expand that concept to fit.
Then I would load the documents via AJAX, and this could probably replace frames completely.

How to make pure css floating tooltips (absolutely positioned span) dynamically resize to accommodate text

I recently had an idea for using the CSS pseudo-class :hover to display a styled tooltip when the mouse is hovered over a link.
The basic code for the link looks like this:
.hasTooltip {
position:relative;
}
.hasTooltip span {
display:none;
}
.hasTooltip:hover span {
display:block;
background-color:black;
border-radius:5px;
color:white;
box-shadow:1px 1px 3px gray;
position:absolute;
padding:5px;
top:1.3em;
left:0px;
max-width:200px; /* I don't want the width to be too large... */
}
This link has a tooltip!<span>This is the tooltip text!</span>
The result is exactly what I want, but with one annoying problem: the span does not expand to accommodate text, and if I don't specify a width, the text is squashed.
I did some searching on Google, found a couple examples of work people had done (this example is creepily similar to what I've gotten), but no one seems to have addressed the span width problem I'm having.
I know this answer is extremely late, but it appears the key to your issue would be to use:
white-space: nowrap;
inside of your span, and get rid of any sort of width definition. Of course the drawback to this will be that the tooltip will only be able to support a single line. If you want a multiline solution you will most likely have to use javascript.
Here is an example of of this method:
http://jsbin.com/oxamez/1/edit
An added bonus is that this works all the way down to IE7. If you do not need to support IE7, I would suggest folding the span, and img styles into a :before, and :after for the .tooltip. Then you can populate the text using the data-* attribute.
I don't think there's a perfect solution to this problem with pure CSS. The first problem is that when you place the span inside the a tag the span only wants to expand as far as the width of the link. If you place the span after the the a it's possible to get close to what you're trying to do but you'll have to set the margin-top: 1.3em and then have to set a negative margin to slide the tooltip left. However, it's going to be a fixed setting so it won't sit exactly at the start of each link.
I whipped up a jQuery solution that sets left dynamically (and a nice little fade effect for good measure).
Demo: http://jsfiddle.net/wdm954/9jaZL/7/
$('.hasTooltip').hover(function() {
var offset = $(this).offset();
$(this).next('span').fadeIn(200).addClass('showTooltip');
$(this).next('span').css('left', offset.left + 'px');
}, function() {
$(this).next('span').fadeOut(200);
});
These tool tips can also be integrated into a word press theme easily. Just copy the CSS into your style. Css file and when creating your posts, just take help of the HTML code and create your own tool tips. Rest is all styling, which can be altered according to your own choice. You may also use images inside the tool tip boxes.
http://www.handycss.com/how/how-to-create-a-pure-css-tooltip/
Even though this question is a bit older already, I would suggest the following compromise:
Just use max-width: 200px; and min-width: 300%; or so,
whereas the min-width could result higher than the max-width.
Just figure it out.
This way you could not have entirely liquid tooltips but the width would stand in kind of a correlation with the width of the containing link element.
In terms of optical pleasantness this approach could be of value.
edit:
Well I must admit it is nonsense what I wrote. When the min-width can be higher than the max-width, there is no sense to it.
So just putting the min-width in percent would achieve what I tried to suggest.
Sorry for that.
I found this and it was working for me. It's a good solution when you have a lot of elements and jquery plugins on the same page and you can't work with
Text <span>Tooltip</span>
View pure CSS solution: JS BIN
Credit to trezy.com