Question

I have a quite large Flex application with a large set of views and I ceratain views I’d like to add shortcuts.

And i’m looking for something like:

<mx:Vbox>

<foo:Shortcut keys="ctrl+s" action="{bar();}"/> 

....

</mx:VBox>

Is there any framwork or component already done that does something like this? I guess it should be too difficult to build? When building this I only want the shortcuts to be active when the view is visible. How do I detect this? What base class is best to inherit from when working with non visual components?

Answer 1

I don’t know of any framework component that does that already, but the examples above should get you started if you try to build your own.

There’s no need to inherit from any component for a non-visual component like the one you’ve described here (your “foo” class needs no parents.) There’s nothing in the Flex framework you need to inherit from for this.

However you architect it, your foo class is going to have to take in and parse keyboard codes to listen for and accept one or more methods to call. All you have to do is figure out when to add and remove the event listeners that will call the passed-in methods.

To handle turning your keyboard events on and off based on visibility, just have your foo component bind to the “visible” property of it’s parent and add/remove event listeners accordingly.

You might also consider having the listeners added when the component that foo is nested in is on the display list rather than just visible. To do this, simply added and remove your event listeners in one of the component lifecycle methods – probably commitProperties is the most appropriate.