I am using FXML via Scene Builder to establish some JavaFX scenes and formatting templates. Having scanned the web and Oracle tutorials, I still find determining the 'rules' around how layouts size/wrap/fit-contents/etc. and spacing between elements and compoents to be 90% a black art to me. What I'm missing is the "layout overview" (missing chapter) that puts FXML (and JavaFX) layouts all together. If you've come across such a creature, please share link(s).
To date I've only found small bits of information. For example the:
JavaFX References
JavaFx JavaDocs
Java CSS Reference
Give some useful infomation on one attribute, parameter or characteristic. There seems to be nothing outlining the big picture nor making an effort to connect the dots between say "font-family" to (what are) "valid fonts"?
Also I'm looking for some examples that do more business or applications type work. More real-world(tm) examples like a data entry form that takes details with text fields, comboboxes, radio buttons, etc. Doing 'normal' on-screen things not just looking shiny graphics to show what JavaFX might do.
The main thing that I see as missing is a description relating the different JavaFX containers and elements and relating them together for formatted-appearance, formatted-layout, rendered-sizing relating to each other.
Forgive me for giving an example that sounds like a critism, it isn't intended to be I simply haven't found the information to let me satisfy some simple requirements:
Want a dynamic layout that will work on different sized displays/windows.
Some screne areas will need to size according to the content. More or less what I'd describe as, fit-to-content.
Other areas may need to be fixed width or height (as constraints).
The remaining parts of the formetted-layout would shrink or grow depending on the size and capacity of the window.
I want this in FXML: so that we can have a menu of layout styles with the same information (as views). That way we are expecting to match display with the best layout.
I can list the main, specific roadblocks I've come across (next). The thing I accept is that there are gaps in my knowldge and in what I'm reading about how containter work, how do min-prefered-max widths and heights work? How to they interact, etc.? That may be too large a question for now. I can give an example and some specifics to follow and leave it to the wisdom of the crowd ...
Example
| col-01 | col-02 | col-03 | col-04 | col-04 |
| | | | | |
| expand | fixed | scale | expand | fit |
| | percent |conetnet| | content |
| | | | | |
Specifics:
If I used a GridPane, there is NO properties or style field in SceneBuilder for the columns or rows.
Question: can I code style for GridPane rows and columns in the FXML file?
Percentages are not valid in most places (Java CSS Reference). Where can we use a percent and not use percent.
I want the columns with "expand" to grow/shrink according to the display size.
Fit content shouldn't expand (or only expand moderately).
Scale content should expand/shrink to suit the 'remaining space' and at the same time I want the content to 'fit-space' (which will normally be a graphic or other media)
What are the VALID CSS styles for elements.
What are the VALID values for the different JavaFX CCS styles?
Which style (path) selectors and combination work for JavaFX?
I still believe these constraints are do-able with JavaFX. I want the "outline rules" for my layout to be set-up in FXML. I feel that FXML should capable of doing what's needed provided I get the inforation about how to combine and set-up my layouts to satisfy the deploymed display constraints.
I'm expecting all these answers are not all in one place. As this is my second time (project) where I needed to know these things. I would prefer to get things working with a little less brute force this time because we want the flexibility offered with FXML definitions. I also think lots of us want to know how to do this but JavaFX styling is not the same as HTML. My thanks in advance.
see also:
FXML Guice, could be very useful.
Almost all of your specific questions can be answered by using the ColumnConstraints on a GridPane. Have a look at the "Work with layouts" chapter in the official tutorial.
Note that, unlike HTML (where CSS is used for both style and layout), in JavaFX CSS is not really intended to be used for layout, but just for the "look" of the application. (Clearly, there are some gray areas here, such as borders etc, but in my opinion there's a genuine difference in approach.) I think the question on percentages in CSS values becomes a moot point once you realize this difference.
For your specific example, and just off the top of my head, so this may not be exactly correct, you can do something like:
<GridPane>
<columnConstraints>
<ColumnConstraints hgrow="ALWAYS">
<maxWidth><Double fx:constant="POSITIVE_INFINITY" /></maxWidth>
</ColumnConstraints>
<ColumnConstraints percentWidth="20"/>
<ColumnConstraints hgrow="SOMETIMES" fillWidth="true"/>
<ColumnConstraints hgrow="ALWAYS">
<maxWidth><Double fx:constant="POSITIVE_INFINITY" /></maxWidth>
</ColumnConstraints>
<ColumnConstraints hgrow="NEVER" />
</columnConstraints>
<!-- Nodes... -->
</GridPane>
In SceneBuilder (screenshot is from 2.0, but this worked in 1.1 too), click on the "header tabs" for a column and under layout on the right you will be able to set the column constraints for that column. In this screen shot, column 1 is selected (its "header tabs" are yellow):
For your specific question 6, about css styles, I've found the CSS reference is pretty explicit about that, once you figure out how it's laid out. It lists the types and the values they take, then lists nodes, the attributes that can be used with them, and their type. The selectors are the standard css selectors, with a few pseudoclasses not being supported (documented in the introduction of the reference).
One thing that's not stated explicitly in the reference is that the "substructure" section for each Node is listing css classes. So, for example, ScrollBar (which has css class scroll-bar) has "track" listed under its substructure as a StackPane. StackPane is listed as defining a property -fx-alignment as well as inheriting all the properties of Pane, which in turn inherits all the properties of Region, such as -fx-background-color. So if I want really ugly scroll bars, I can do
.scroll-bar .track {
-fx-background-color: purple ;
}
And if I want one particular scroll bar to be ugly, I can give it a style class (say "ugly") and do
.scroll-bar.ugly .track {
-fx-background-color: purple ;
}
(So the usual selection rules for css apply.)
While the reference is pretty good, I do quite often dip into the default stylesheet source code to see how things are done there. This is a useful resource, and Oracle seem to actively encourage you to look at this. As well as the link from before, you can just extract it from the jfxrt.jar file with
jar xf JAVA_HOME/jre/lib/ext/jfxrt.jar com/sun/javafx/scene/control/skin/modena/modena.css
Related
I'm trying to make a two-lines menu with bootstrap 4, and I found some examples on the web:
https://www.codeply.com/go/DpHESPqZsx
https://www.codeply.com/go/cxXqBnGrPx
In the first example they use "div class='navbar'" to create the menus.
<div class="navbar">...</div>
In the second example they use "nav class='navbar'" to create the menus.
<nav class="navbar">...</nav>
Which is the correct way? Which one should be used?
I have another question. Why do they NOT use the bootstrap grid with the rows and columns? When should you use it?
Thank you very much
Div and nav are similar element, in terms of what they do. However, nav is better in this situation because you want to have semantic markup. It is because of SEO and more readable for developers.
And why they are not using grid is probably because they haven't implemented it yet and should be coming. Their grid system is done with flex currently, but should change. And CSS Grid does not work that great with IE11.
You should use Grid when you feel that it will be easier to structure your site. It's a great tool, and combine it with Flex is so easy and comfortable
The difference is that a div has no meaning and a nav Element has a semantic meaning (indicating that there is a navigation). You can remove every div and span from a website and have no difference about the semantic structure of a page, every other element has a meaning: For example, states that there is the main content, says here is the header-part of the site.
These parts tell for example search engines what's on a site. So if you have the text "Stackoverflow" in your Element somewhere, google (and other search engines) know that you have a stackoverflow link in your navigation. If you have it in your Tag, you probably have a text about stackoverflow.
Keep in mind: These are some simplified examples.
The html5 nav tag has semantic meaning.
Please follow the Bootstrap docs. The grid (row>col) should not be used in the Navbar as it's not a supported component. Using the grid inside the Navbar will through off alignment, spacing and the responsive behavior controlled by the navbar-expand-* classes. I'm the author of both Navbar examples from Codeply you posted.
I would like to add tooltips (or hovering behavior) on SVG diagrams generated by diagrams.
Is there a way to add custom properties to a diagram , or worst comes to the worst be able to set and id to things, so they can be referred to in Javascript.
The question is slightly misleading because the title property that gives tooltips on SVGs in browsers is not an attribute, but an element of its own. You add tooltips, that is SVG titles, with the method svgTitle in Diagrams.Backend.SVG.
The same module also contains methods svgID and svgClass to add these attributes to allow external javascript to find specific SVG elements.
I kept googling, and havn't tried it yet, but I found this. It seems to exist to exactly satisfy your need.
It is SVG backend only.
I need to set the width of an element that is used in various places in my fluid Susy layout. The parent element is not always the same width, but I want this element to always have the same width relative to the page width.
Example:
In a 12-column grid, a news article sometimes spans 12 columns, sometimes 6. Editors are able to add a <blockquote> in the news article text. I want a blockquote to always be 3 columns wide (relative to the full page), regardless of its context (12 or 6 columns).
Of course if this was a grid with fixed column widths it would be easier, but I'm looking for a fluid, percentage-based solution.
PS. I am willing to use Susy 2 alpha if that makes it easier to solve the problem.
You would do this the same way in Susy 1 or 2, though it's always more fun in 2. :)
The issue isn't really related to anything specific about Susy, it would be a problem in any fluid CSS situation. You can only solve it if you have a hook for knowing which context you are in. At that point, you can solve it from either end. Something like this:
blockquote {
#include span-columns(3);
.narrow & { #include span-columns(3,6); }
}
There really isn't any way to do it without the hook. CSS doesn't have element-queries (and isn't likely to any time soon, for the reasons given in that article).
Setup:
I am using Orchard CMS 1.6.
I have a site where I need to be able to set the background color of the whole page. Ie, I need to style the body tag.
I could use the LayoutSelector module and have distinct layouts. However, the only difference in each layout is that the background-color rule for the body tag is different. So it seems a very un-dry way of doing things.
I can't find any way to make Vandelay.Classy add a distinct id or class to the body tag (it adds, as I understand it) an id or a class to the outer tag of a content type. In my case, that isn't the body tag.
So that is no good, I really do need to customize the body tag.
How to do this?
Note:
I need 3 different background colors. I also have a two column layout and a three column layout. [I use (a modified version of) the layoutSelector module to achieve this.] So to have 3 different colors of background, and I used layouts to achieve this, I would need 6 different layouts: TOTAL overkill.
There must be a better way...
From any cshtml file, you should be able to access the Layout shape. From pretty much anywhere else, you can still get to the Layout shape through WorkContextAccessor. Once you have a reference to the Layout shape, you can do Layout.Classes.Add("the-class-you-want").
At the top of many pages in our web application we have error messages and notifications, 'Save' and other buttons, and then our h1 tag with the content title. When making a web application accessible, is it ever acceptable to have content above the top-level structure tag like we do here?
As a screen reader user I don't like content above the main heading. Normally I navigate by headings so would miss the error message. A better solution is to output an h1 heading above the error message, then leave the rest of your headings in tact giving you two h1 headings.
Yes (you can put stuff above them). The H simply means Heading. It's a question of what the heading relates to I guess.
My only caveat is, H2 shouldn't really be above H1, and H3 Shouldn't be above H2. But I don't think it's an actual rule.Websites have menus, warning, notifications. It's acceptable to put them above the rest of your content. I don't see how it would affect accessibility as long as your content is ordered logically. Look at the page CSS turned off. Does it look logical? That's the most important part of accessibility.
Although some people do go that extra mile and have the menu as the last item in the markup and use CSS to bring it back to the top. Personally, I find that solution counter productive. The menu is still important, it belongs at the top of the page.
Yes, just consider it is in that order that the user will get the information. So, if you just did an operation it sounds like a good idea to get any message related to it as the first thing. If it is a notification that appears on any page unrelated to what you are doing, I wouldn't put it above, as it might be a little weird.
Also you can use a text browser that doesn't use styles, it should look like a document with appropriate headers.
Heading tags are used to indicate the hierarchy of the content below it. You should only have one h1 tag and it should be the first content to appear on your page (this is usually the name of the site). Also, you shouldn't skip heading tags when drilling down through different tiers of content.
In your case, you can still use CSS to position items above the h1 tag as long as it is in the correct order in the html.
I assume the elements above the heading are used by JavaScript. In that case, it's preferable if they are created by JavaScript, not included in the source of the page.
To return to your original question, it is probably best that they be at the foot of the page. However, if they are hidden using the CSS "display: none;" or "visibility: hidden;" properties then they will not be seen by most (perhaps all?) screenreaders or by many other assistive technologies, and so should not be an issue. I've written a fairly detailed explanation of why accessibility technology ignores such elements.
Of course if somebody disables CSS things are going to look pretty messy. If there is content on the page that can be used even when CSS and/or JavaScript are disabled, then putting those elements at the bottom of the page will at least make things less cluttered.