I know that it is possible to get the selected value on the change handler or item click handler of a radioGroupButton. Like this:
protected function rb1_itemClickHandler(event:ItemClickEvent):void
{
var selectedValue:String=event.currentTarget.selectedValue.toString();
}
But what I need is the index of the selected value. Any idea how to do that?
Check out event.index like in this example:
protected function rb1_itemClickHandler(event:ItemClickEvent):void
{
trace(event.index);
}
Related
I am using a s:TextInput in Flex 4.5. It shows it's prompt text if the underlying text value is null or empty String. Does anybody know if I can make either don't show the prompt on empty String or even show a different prompt?
I already found a way by extending the TextInput class and overriding some of the methods but I am still hoping anyone here knows an easier way ;-)
Ok, so based on the comments, here it is:
You store the current prompt value in a private variable, like so:
private var _inputPrompt:String = "";
Then you create a getter, so the value is accessible from outside of this class:
public function get inputPrompt():String
{
return _inputPrompt;
}
Now you can bind inputPrompt anywhere you need it, however, the problem is the getter won't be recalled once the private value changes. You can fix this very easily: Create an update method, for example like so:
public function updateInputPrompt(value:String):void
{
_inputPrompt = value;
}
Ok, nothing fancy so far. I'm guessing this is the point where you are right now. In order to "force" the getter to be recalled, you have to bind it to an event, like so:
[Bindable(event="inputPromptUpdated")]
public function get inputPrompt():String
{
return _inputPrompt;
}
Finally, you can simply dispatch this event when the value is update (i.e. in the updateInputPrompt method):
public function updateInputPrompt(value:String):void
{
_inputPrompt = value;
dispatchEvent("inputPromptUpdated"); // For binding
}
This way, the getter will be recalled every time you dispatch that event.
Hope this helps. Have a great day, and a great weekend!
I'm not sure if the way I did makes the garbage collector remove the timer. Here are my two functions:
public function newWave() {
var callTimer:Timer = new Timer(800);
callTimer.start();
leftToSpawn = 4;
callTimer.addEventListener(TimerEvent.TIMER,waveCall);
}
public function waveCall(e:TimerEvent) {
leftToSpawn--;
if(leftToSpawn <= 0){
e.target.stop();
e.target.removeEventListener(TimerEvent.TIMER_COMPLETE,waveCall);
}
spawnEnemy();
}
Thanks
To remove an event listener you need to remove it with the exact same signature.
If you do:
.addEventListener(TimerEvent.TIMER,waveCall);
Then you need to use the same event type and function to remove it:
.removeEventListener(TimerEvent.TIMER,waveCall);
Using TimerEvent.TIMER_COMPLETE here will try to remove a listener that doesn't exist, which is silently ignored.
Using target here is ok, for other listener types you may need to use currentTarget, which is always the object the listener got added to. For example in a mouse click event, target could be a child of a MovieClip and without any listeners.
Moreover, timer already has ability to repeat specified number of times and the correct code will be like this:
public function newWave() {
var callTimer:Timer = new Timer(800, 4); //repeat 4 times
callTimer.start();
callTimer.addEventListener(TimerEvent.TIMER,waveCall);
}
public function waveCall(e:TimerEvent) {
spawnEnemy();
}
just change:
e.target.removeEventListener(TimerEvent.TIMER_COMPLETE,waveCall);
to
e.target.removeEventListener(TimerEvent.TIMER,waveCall);
I'm implementing some kind of combobox control (by extending spark.components.supportClasses.DropDownListBase)
Now, inside this control; I need to know:
if the dataprovider is changed/assigned. (which I can do... the first approach below works);
if any item in the dataprovider collection has changed.
I tried 2 methods that did not do the trick...
1ST APPROACH:
[Bindable("collectionChange")]
override public function set dataProvider(value:IList):void
{
if (value) value.addEventListener(CollectionEvent.COLLECTION_CHANGE, onDataChange);
super.dataProvider = value;
trace("DATA CHANGED"); //fires
}
protected function onDataChange(event:CollectionEvent):void
{
trace("COLLECTION ITEM(S) CHANGED"); //does not fire
}
2ND APPROACH:
Since this is based on DropDownListBase; it should dispatch the CollectionEvent.COLLECTION_CHANGE event already..?
public function myClass() //constructor
{
addEventListener(CollectionEvent.COLLECTION_CHANGE, onDataChange);
}
protected function onDataChange(event:CollectionEvent):void
{
trace("DATA CHANGED"); //does not fire
}
Any ideas?
UPDATE: Edited above.. The first approach lets me know if the dataprovider is changed but not if any item is updated in the dataprovider collection. The second approach does not work at all..
We'll be able to help significantly more if you show us a runnable sample to demonstrate the problem.
if the dataprovider is
changed/assigned.
Your first approach should work. Can you tell us what makes you think it didn't? ( No trace statement I assume? ). And tell us what you did to change the dataProvider.
The second approach won't work because myClass is not firing off the collectionChange event.
2 if any item in the dataprovider collection has changed.
There is not really a way to tell this. In most cases, a collection is just a list of pointers to other objects. If you change those pointers, then a collectionChange event is fired. IF you change the item that he pointer is pointed to, the collection has no way to know that something changed. Binding works very similarly if your an MXML fan.
If you have control over how items are changed, you can deal with it that way. Instead of:
(collection.getITemAt(x) as myObject).property = newValue;
Do something like this:
var myObject : MyObject = collection.getITemAt(x) as myObject
myObject.property = newValue;
collection.setItemAt(x, myObject);
I would expect that to fire a collectionChange event, but not the former.
That said, in the context of a dropDownListBase: As you scroll or open and close the drop down, the itemRenderers should be updated to reflect the most current dataProvider's data. But if you change something on the fly while the drop down is open, I would not expect it to update automatically [if you're not changing the dataProvider.
Hello i have a function as following:
private function seatClickHandler(e:MouseEvent):void{
var check:Check = new Check();
if(e.target.contains(check)){
e.target.removeChild(seat);
}else{
e.target.addChild(check);
}
}
basicly i want to check if e.target contains a child called check. If it does i want e.target to remove the child, else i want to add the child. But the method i tried doesnt seem to work although i think this is the way to go. Any suggestions?
When you declare your Check object, Actionscript creates a reference code for that specific object.
So the first time your code is run, your Check object could be given a reference of #c0ecc29. Your if statement checks to see if #c0ecc29 is a child component of target. It won't be, so the Check object with reference #c0ecc29 is added to target.
The second time the clickHandler is called, a new instance of the Check object is created which will have a new reference id. Your target has the original Check object with the #c0ecc29 reference so it won't get removed.
The correct way to get this working depends on what target is (DataGrid, Group, etc.).
EDIT:
Based on your comments, I would try something like this. It checks to see if the Check object is a child of target and adds it if needed. Then when the Check object is clicked, it will toggle its visibility.
public var check:Check = new Check();
private function seatClickHandler(e:MouseEvent):void
{
if(!e.target.contains(check))
{
check.addEventListener(MouseEvent.CLICK, check_handleClick);
e.target.addChild(check);
}
}
protected function check_handleClick(event:MouseEvent):void
{
check.visible = !check.visible;
}
If you need to actually remove the Check object from target instead of just changing its visibility, you could try this:
public var check:Check = new Check();
private function seatClickHandler(e:MouseEvent):void
{
if(!e.target.contains(check))
{
e.target.addChild(check);
}
else
{
e.target.removeChild(check);
}
}
If the child is named 'check' then you should be able to use getChildByName(). See flash.display.DisplayObject.name
If you happen to have the child in memory, you can use getChildIndex()
check is a new object in the scope of that function, so it will not be a child of the event target.
What you want to do is declare check as a global variable (And also cast target as DisplayObjectContainer).
e.g.
private function seatClickHandler(e:MouseEvent):void{
if((e.target as DisplayObjectContainer).contains(check)){
(e.target as DisplayObjectContainer).removeChild(seat);
}else{
(e.target as DisplayObjectContainer).addChild(check);
}
}
However I'm not sure if this is exactly what you want to do (There can only be one check). A better approach would be to have a function (maybe toggleCheck) on the target, and have that display object responsible for rendering the check (And removing it)
This worked perfectly fine for me in my situation:
if(possibleChild.parent == holder)
holder.removeChild(possibleChild)
It may or may not be exactly what you're looking for.
I was trying to filter a combo box dataprovider based on the values in the text boxes . When the contents of the dataprovider changes Combo box automatically calls change event method . Please find the sample code below.
Filter Utility Function:
private function filterLocations(event:FocusEvent):void {
locationsList1.filterFunction = filterUtility;
locationsList1.refresh();
}
public function filterUtility(item:Object):Boolean {
// pass back whether the location square foot is with in the range specified
if((item.SQUARE_FOOTAGE >= rangeText1.text) && (item.SQUARE_FOOTAGE rangeText2.text))
return item.SQUARE_FOOTAGE;
}
// THIS WOULD BE CALLED WHEN COMBO BOX SELECTION IS DONE
private function selectLocationsReports(event:ListEvent):void {
selectedItem =(event.currentTarget as ComboBox).selectedItem.LOCATION_ID;
}
When the DataProvider gets refreshed its automatically calls change method and was throwing Null Pointer function because its prematurely calling the above selectLocationsReports method and its throwing error.
Can somebody let me know how to stop the CHANGE event from propogation when the dataprovider is refreshed.
You can't stop a CHANGE event, just don't add an event listener unless you are prepared to get the event. I don't see where your event listener for Event.CHANGE is in the code above.
Just be sure that you don't addEventListener(Event.CHANGE, selectLocationsReports) until your ComboBox is ready for it.
The other thing to do (on top of Kekoa's response) is put an if statement in the event handler, and check to make sure the data is there before you begin working with it.
A handy syntax I use frequently for this is
if(dataprovidername) {
}