In JavaFX, I'd like to provide a read-only view with full support for navigation and copying to the clipboard.
I need the capability to scroll a ScrollPane and to switch tabs on a TabPane. I need the capability to make selections so the user can copy. Because disabling the controls undermines these capabilities, disabling the controls will not work for me.
It would be nice if the implementer of the view didn't have to know about this read-only business and I could impose this read-only state upon the view from the outside, by recursively visiting all of its nodes.
TextInputControl.editable seems to do exactly what I need.
However, ComboBoxBase.editable only prevents the user from typing into the control, not changing the selected value. (But, there is this: How to make checkbox or combobox readonly in JavaFX, which works for all descendants ofButtonBase too.)
Related
I have a design that displays a list of content that you can filter by different categories. Each filter is displayed in a dropdown menu that lets you choose one or more options, which when activated (either through click or keyboard), will update the results on the page. The page url does not change in response to the filter and there is no "submit" button to apply the filter.
I'm confused which ARIA pattern to use: Menu (with menu/menuitem roles) or Combobox (with listbox/option roles).
In my opinion you should go with a combobox.
Otherwise, it should be a menubar rather than menu:
A menu that is visually persistent is a menubar.
Managing focus
Aside from the question which role to use, you need to decide whether to manage focus or not. It is recommended (should) for menu and menubar, which would mean that the whole bar only has one tab stop, and navigation between the single dropdowns is done via arrow keys.
Website or application?
This depends on how much your site feels like an application overall. If it’s more of a website, keyboard users in general are more accustomed to tabbing than to managed focus. For users it is sometimes a surprise that you need to navigate within components by means of arrow keys.
If there are other composite widgets as well that manage focus, you absolutely could do so for this part as well.
Responsive Design
A menubar should allow left and right arrow keys to navigate the filters, and up and down to focus the options. Managing focus would get complicated with Responsive Design: Once items wrap, it becomes less obvious how to navigate to them.
Actions vs Selections
A menu is usually used for actions. To quote some references (emphasis mine):
A menu is a widget that offers a list of choices to the user, such as a set of actions or functions.
– Menu or Menu bar pattern
The WAI ARIA standard defines an actual `nole="menu"' widget, but this is specific to application-like menus which trigger actions or functions.
– Bootstrap
Since the filters only allow choosing options, and not executing commands or functions, I would rather go with combobox.
Searchability
Combobox also implies that it’s a flat list of options, maybe grouped. This is immediately known. A menu can potentially have sub menus, so it’s less clear what to expect when opening a filter list.
Since combobox is a flat list, users can type Printable characters to directly jump to a list item. This is not the expectation for menus.
Show the user’s selection
Since the filters close once a selection is made, it is best practice to display the chosen value or values in the closed item. Also known as the Visibility of System Status.
A combobox will do so, and screen readers would even announce the current choice without opening the list. A menu does not have that behaviour.
problem is I have a spark Tabbar, with many forms in each tab.
But I have a single global save button. Problem is, if I don't open a Tab,
it doesn't get initialized and therefore the forms it contains do not exist..
How Can I make it as if the user had clicked on every tab?
The best way to handle this is to have a data model that each tab is displaying and editing, rather than trying to go in and read the values out of the controls in each tab, and save those. This is at the heart of MVC.
However, if you're too invested in your current architecture to be able to change it and you are using a ViewStack with your TabBar, you may find that setting creationPolicy to "all" does what you want. If you're using States, I don't think you can force all of them to be instantiated without putting your application into each State at least once.
When I try to access the hidden TABs of my tab navigator control in action script, it returns a null error. But it works OK if I just activate the control in the user interface once. Obviously the control is not created until I use it. How do I make all the tabs automatically created by default ?
<mx:TabNavigator creationPolicy="all"/>
That should do it. Deferred instanciation is a feature, but sometimes it is a hassle.
The Flex framework is optimizing creation be default (creationPolicy="auto") so if you have a configuration dialog with a lot of tabs, for example, and the most useful tab is the first one, your application does not spend time and memory initializing the tabs that the user never sees.
This makes a lot of difference when dialogs like this never release, and is a good default to go with.
One thing to look at is using a private variable in your dialog/form instead of pushing the data to the control on the hidden page. This style treats the whole form as if it were a component, which it sort of is. To repeat: the MXML form/dialog/canvas is a class, and it can have data and methods in addition to containing other components.
Cheers
On a side note, I've run into the deferred-loading policy in a multi-state application, and circumvented it by forcing all elements to be included and invisible in the initial state. Something to consider, but only as a hack.
Our product team has requested custom cursors during drag/drop operations. They have provided me with three images to implement:
Open-Hand-Grabber.png: displays when a user hovers over an item that they can drag
Closed-Hand-Grabber.png: item is being dragged
Closed-Hand-Grabber-No-Drop: item dragged over an area where it cannot be dropped
I have embedded these images into the Flex application and I am now trying to implement the desired behavior.
My first thought was to listen to the drag/drop events and set the cursors using the CursorManager.setCursor() method. This solution seems very code intensive and I feel that there must be an easier way to skin the various drag/drop cursor states.
Any ideas?
Check out the various cursor styles available on the DragManager class:
copyCursor
defaultDragImageSkin
linkCursor
moveCursor
rejectCursor
http://livedocs.adobe.com/flex/3/langref/mx/managers/DragManager.html
I want to create a combobox in flex which will take three values, Available, Unavailable, and Busy. The constraint is, I should not allow user to go directly from Unavailable to Busy. So when a User is selected Unavailable, I should keep the Busy item disabled (unselectable), but a user will be able to go directly from Available to Busy. I chouldn't find a straight forward way to disable an item in combobox in Flex. How can I do that?
Have you considered using radio buttons rather than a combo box? It's clear how to do this for radio buttons, for one thing. Also, it can often be friendlier to present the available options without requiring a click to reveal them. (Especially if, as in this case, you are adding the possibility that an option is "available, but not possible for you right now for some reason not shown in this combo-box item").
If you really want a combo-box, you can use the click event to display it in a non-standard fashion by probably changing its style; and then, if clicked anyway, Then, in the selected event, reject the choice (hopefully with an indication of why),
Or, if you want to simply remove it from the list, you can have the click listener event repopulate the source list each time, based on conditions. But that might be confusing to the user, too.
You can also have a look at
www.stoimen.com/blog/2009/03/05/flex-3-combobox-disabled-options/
which references
wmcai.blog.163.com/blog/static/4802420088945053961/
(note for NoScript users you must have 163.com and 126.com at least temporarily allowed to be
able to properly see this page)
it works very well even though I added the code for being able to properly handle keyboard
events in the dropdown list
Full self working example available at
http://olivierbourdon.homedns.org/OpenSource/combos.zip
Thanks again for the good work