I'm currently building a Flex 4.5 mobile project including several views and custom written MXML components that can be incorporated dynamically into those views.
How do I determine which component currently has focus, namely has been activated by the user tapping on it?
The background for this is a global search function in the main application. Depending on the results of this search, fields in the custom components are set. Given that I don't want all components in a view to listen to the outcome of that search function, I have to check which one is currently active.
I'm trying to bind the selected object (the result from the search function) to the active component.
Any help would be much appreciated.
Cheers!
You can determine which component currently has focusing using the FocusManager.getFocus(). Conceptually something like this:
var ComponentWithFocus : IFocusManagerComponent= FocusManager.getFocus();
Related
In the examples for RobotLegs, it appears that mediators are used on every button/textArea, rather than on the custom component that contains these children. This would be very time consuming would it not?
From Joel Hooks InsideRia Example
Dependency injection works better with
unambiguous classes. What this means
is that by extending TextArea into our
new MessageView class, we are creating
a specific view component for the
dependency injection to act upon. This
is important if our application were
to have several TextAreas that served
different purposes. By dividing up our
classes in this way, we are clearly
defining the intent of the class and
allowing for the dependency injection
tools to do their jobs effectively.
No, don't mediate every child component. Your components should be organized into groups that perform related actions. In the examples the components are extremely simple and do not reflect what a real application would look like.
One rule of thumbs I use is thinking if that component needs any communication with the rest of the application, or if its only a part of a whole. Keep in mind that mediator are only intended to serve as a bridge between the view and the app.
For example, if I've a view with a form (asume a login form) I don't mediate all the child components (the textfields, the buttons, etc.) because it would be pointless and would have a proliferation of classes and objects on runtime. When I do the form I think, what does the view by its own? and what the other parts of the app should do with it?
When the user fills the form and clicks a button, the view dispatches an event (LoginRequestEvent, for this case), and then the mediator should redispatch that event, making the mediator very lean.
But with practice of the framework, you'll come up with this feel of what you shold mediate. For instance, in one app I mediate every item renderer of a list, and on other I mediate a view stack with two or three navigation contents.
Hope it helps
I have a Flex application with three different views. Only one view is shown at a time, and the choice of view depends on what part of the application the user is working with. If it had been an ordinary HTML webapp I would have created three different HTML-templates/pages for each view.
What is the recommended way to handle such application views in Flex?
The behavior you want is usually accomplished by using a ViewStack component. In MXML you declare child containers for each view you want, but only one gets shown at a time. You can change which one is shown programmatically whenever conditions are met by setting selectedIndex on your ViewStack. By default the first child container is displayed when run. Another approach is to declare and use states in your container and change currentState whenever you need to change the view. Hope that helps.
I am new to MATE framework and I have been digging around some sample codes so that i can do the following:
On clicking a button (on a canvas)
Display a Panel.
The issue is that i am not trying to pass any value hence not sure of how/ what should be defined as sourcekey and targetkey. If this is the case, then how should one define the propertyinjector details.
most examples that are floating around contains details of reading data from a source and populating the same on a UI/ Display component.
Thanks
Srinivasan S
for this one you shouldn't use propertyInjection you should dispatch an event (you can make it custom), then you need to catch the event in the appropriate place and simply do whatever you want with it.
In an AIR application, I have a link button for winner statistics. If I click this button, then the statistics are shown on a full page (Canvas) in my application. I have already created the statistics using the Canvas component. Which container is typically used for viewing such data?
Any references? I tried a ViewStack, but will it overwrite the Main page?
Could you give some more information? If you are trying to show tabulated data, you can try a DataGrid. If you have a component you would like to list, then a VBox would work and you could just add your winner stats component to the list.
I understand that we need to create MXML file to define a view. Suppose on user click of a button I want to show another view defined in another MXML file. How can I do this?
You could use a viewstack. each item in the viewstack would be a different MXML file so when the user clicks a button you change the selected index of the viewstack which makes the view change.
You could probably do with checking out the examples in http://www.adobe.com/devnet/flex/tourdeflex/ this will help explain so much more than a simple answer will.
From your question it sounds like you need to get the basics of flex first and the tour de flex app contains loads of examples with source code.
HTH.