Draft.js get selection or span for already styled elements - reactjs

I'm using react-rte but am willing to extend it so let's talk about Draft-js.
I need to be able to "inline-style" a selection. Then on subsequent renders re-access that selection's dom.
So let's say I highlight a selection. Then I persist the document. Then I come back, reload the document, I need to be able get access to that highlighted section, but in the dom.
Basically on the side of the document I'm applying markers, outside of draft-js, and those markers need to line up with the highlighted part. So when I do the initial highlighting I can get the dom position from window.getSelection(), and i can place my marker. But the dom may change later and I won't be able to place my marker.
--edit--
So another use case is that I highlight a selection, and even in the same session, I need to change the color of the selection programatically so again I need to access the section of the document even if the cursor is not on that section.
--end edit--
So what I really need is something like an unique classname, id or even better a react ref for the new spans that are created when you do an inline style.
Please let me know if you need a better explanation.

The SelectionState records the selection, including start block, start offset, end block and end offset. It's not problem to save the selection in you code and apply to the editor later.
So what I really need is something like an unique classname, id or even better a react ref for the new spans that are created when you do an inline style.
So the id you want is a SelectionState, tell where the span is in draft-js editor.
UPDATE
You can find the block key which your inline styled text belongs to, in data-offset-key={blockkey}-xx-xx node attribute. The block key helps you find the node from SelectionState.getStartKey()/getEndKey(). Then find the span node by SelectionState.getStartOffset()/getEndOffset().

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How to create custom tooltip on node hover in React Force Graph

I'm working with React Force Graph (2D - https://github.com/vasturiano/react-force-graph) and trying to display custom tooltip on node hover.
This custom Tooltip (dummy component) would display data that's not returned by node - I'd like to add some details to the tooltip, and those are not stored in node data that's returned for example by onNodeHover).
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Does anyone know what would be a good approach to this? How this could be handled? Extra points for working examples :D
So here's the answer:
nodeLabel doesn't accept React Node but can easily accept string. So workaround for that problem is just passing the whole stringified html code to nodeLabel and RFG will handle that! This is the best solution I believe (althou native RFG tooltip doesn't support left/right - top/bottom switching in case tooltip would be cut by the edge of screen, but thats minor problem).
other solution that I wouldn't recommend would be to create useCursorPosition and whenever onNodeHover returns something else than null we can set state of displayNode to true (and display it conditionally based on this state) in positions returned by useCursorPosition. This solution is flaky thou, because sometimes onNodeHover doesn't return null I user scrolls fast outside the canvas boundaries (hence the tooltip stays displayed forever). In this solution it's also recommended to use requestAnimationFrame to limit the listener on cursor position.

How to get the attributes of an invisible WebElement

The webpage I'm testing has a collection of 35 checkboxes.
The input tag is styled in such a way that it is positioned outside the visible part of the page (-9999px). When I want to click on it an ElementNotVisibleException appears. I can click on the label of the checkbox instead so this is not a problem but how to get the information if a checkbox is selected or not. The only way I can imagine is by analysing the page source. Is there another more convenient possibility to get this information?
Things you could try:
you should already have a method like isChecked() to test this, find that method
find the element and check his attribute for when is checked (example checked="checked")
write another selector for that element and check that this selector exists(not visible), example with css: input#elementID[checked=checked] or by value, depending if is a checkbox or radio box
For invisible element you can get his attributes, you just are not able to interact with him and it will fail to check that is visible/displayed.
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Accessibility: Page Loader indicator using aria-live

Issue: I have an accessibility issue that I am struggling with. I have an angular web application. A page loading spinner/indicator is shown when content is loading. And when the page content has loaded the spinner is hidden. This "div" is never removed from DOM.
Content of the loading div are not read (by NVDAor jaws) when the loading div is shown.
<div class='loading' aria-live='polite' aria-label='Do not refresh the page' tabindex="-1">Do not refresh the page</div>
I wouldn't like to change the structure of the application but work around using 'aria tags' to resolve this, just wondering if I will have to do anything more to make aria-live work?
Updated (27/July/2016)
Further clarification: I am not removing the content from DOM but using css to show/hide content (display: none to display: block and vice versa)
aria-live triggers screen readers when an element with aria-live (or text within an element with aria-live) is added or removed from the DOM. In contrast, when you unhide a hidden element, neither elements nor text are added or removed from the DOM, so the element's aria-live property doesn’t come into play.
To get screen readers to announce “Do not refresh the page”, either of these options should do the trick:
You can create the <div class='loading' aria-live='polite'> element and its text content from scratch and then add that element to the DOM.
Or you can start with an empty <div class='loading' aria-live='polite'> element and then populate its text content.
A few other tidbits:
As long as the text inside the element is what you want to be read aloud, you can omit the element’s aria-label='Do not refresh the page' attribute.
For icing on the cake, it can’t hurt to include a role attribute on the div that has aria-live. If you’re not sure which role to use, go with role="status"—that’s a pretty safe bet.
When or if the page is at a state where you no longer need to display "Do not refresh the page”, be sure to reverse the steps above. (That is, if you went with the first option and you added the whole element to the DOM, remove that entire element from the DOM. Or if you went with the second option and you populated the element’s text content, clear out the element’s text content.)
There are several issues with dynamically added or shown/hidden live-region.
Firstly a quote from MDN - ARIA live regions:
Simply including an aria-live attribute or a specialized live region role (such as role="alert") in the initial markup as it's loaded will have no effect.
Dynamically adding an element with an aria-live attribute or specialized role to the document also won't result in any announcement by assistive technologies (as, at that point, the browser/assistive technologies are not aware of the live region yet, so cannot monitor it for changes).
Always make sure that the live region is present in the document first, and only then dynamically add/change any content.
From my personal experience, even if a live regoin exists in the DOM on page load if you use show/hide then NVDA also has a bug which requires a small delay before a text update in a live region after it was shown initially. Apparently because the region didn't exist when the first text was added, so this isn't an "update". Regarding the timeout, you'd need to set it to something greater than the browser's refresh tick. I use 100ms. Disclaimer: I am strongly against such workarounds to make up for the issues with screen readers or browsers but it might be useful for someone in some cases.

Creating Rich Text editor AngularJS

I know there are lots of great rich text editors out there that can easily be ported to angular and plenty of discussion on how to do this, but I'd like to create my own.
I have the basic idea down:
create a text area and watch the input and perform a function as the input changes. I am familiar with the ngBindhtml directive, only to the extent that I can apply it to an element.
Any idea how I might be able to create a function that would render plain text into html?
I've tried it before but ended up using textAngular.
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Well, I also came across this and created my own editor as I was required to add features like Table addition etc. The repo is still under development but you can some idea by taking a look at this plunkr. Unlike old answers, I have tried to keep it as a component so that it can be reused at many other places as required.
You can star this git repo to stay updated or feel free to add your inputs

Conditional Formatting based on layout view

Another question for you Filemaker Pro experts. The database I am developing starts with a Main layout with a number of buttons (e.g. insert new item, show all items, etc.). Each button is associated to a script, which takes the user to the relevant layout. In each of these layouts I show the buttons in a row, and highlight the current layout with inverse colour.
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For instance, Insert new item and Show all items take to the same layout, however in the first case the script views the layout as a form and inserts a new record, while in the second I view as a list and show all records. The layout is the same, though, so I'd need to enact a conditional formatting based on something. How do I do that, and what should I check against?
Thanks in advance for any help.
Regards.
Presumably you are currently using the formula: Get (LayoutName) to decide on your conditional formula, why not try additionally using formulas: Get(WindowMode) and Get(LayoutViewState)?
You could conditionally format the button if (which sends user to MyLayout in browse mode):
Get(WindowMode)=0 and Get(LayoutName)="MyLayout"
Or (which sends user to MyLayout in form view):
Get(LayoutViewState)=0 and Get(LayoutName)="MyLayout"
.
Other functions which may help could be Get(FoundCount) and Get(TotalRecordCount). You can see the entire list of Get functions here.

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