I need to know when a document(screen) is popped off the stack in an Apple tvOS app. I thought detecting the Menu button press would be the simplest way, but I'm using TVJS and have not been able to figure out how to write the event handler.
Please help me write an event handler that will fire on document removal, menu button press or offer an alternative solution.
Subscribe to the event unload - it's triggered whenever a page disappears after being popped from the stack:
doc.addEventListener("unload", Presenter.onUnload.bind(Presenter));
[...]
onUnload: function(event) {
console.log("onUnload");
},
There is such thing of a handler for onDocumentRemoval or similar. What you can do, instead, is create a global select handler:
doc.addEventListener("select", self.doThing.bind(self));
And then check if the fired event comes from one of the buttons used to remove an element of the stack (let's suppose those buttons have a class named delete:
doThing: function(event){
var element = event.target;
if (element.getAttribute("class").contains("delete")){
//enter code here
}
EDIT 1:
I found the possible events the TVMLKit handles (I know it is in Swift/Objective-C, but the events are the same):
TVElementTypePlay
A play event has been dispatched.
TVElementTypeSelect
A select event has been dispatched.
TVElementTypeHoldSelect
A hold event has been dispatched.
TVElementTypeHighlight
A highlight event has been dispatched.
TVElementTypeChange
A change event has been dispatched.
Those events are only attachable to a template as far as I could test. I guessed the change event would be perfect if I could attach it to the navigationDocument to listen for changes, but those two options won't work and both fire errors:
Attached to the global:
navigationDocument.addEventListener("change", function(event){console.log(event)});
Attached to the documents array:
navigationDocument.documents.addEventListener("change", function(event){console.log(event)});
There is no built-in method for those above to listen for any change. The event, though, will work on a template listening to internal changes. But it won't fire when the template is pushed to or popped from the stack.
I am guessing you will need to re-design your app in order to achieve what you are looking for.
How do I make it look like a button was pressed using C# code? If I can actually push the button (play the animation and activate the events associated with the button press) with code that would be even better.
Playing the animation is pretty easy, using the Visual State Manager:
private async void PretendToClickButton()
{
VisualStateManager.GoToState(myButton, "Pressed", true);
await Task.Delay(250);
VisualStateManager.GoToState(myButton, "Normal", true);
}
You can play with the delay as you see fit.
Programmatically raising the event is not possible; you just have to call the handler method(s) directly (which assumes you the code that handles the event).
[Edit: You could subclass Button and provide your own mechanism for simulating the Click event, but that makes the XAML a wee bit trickier]
I'm working on something similar to the Angry Birds "rollout" for options, etc., but I'm running into a fairly substantial problem.
The rollout itself is just a toggle button, with several other buttons added to the display list that move when you touch the toggle button. Each of these buttons is a class that extends Sprite and contains individual methods for touch events, begin, end and out. When these buttons get initialized (NOT instantiated), the touch begin listener is added. Something like this:
public function Initialize():void
{
this.addEventListener(TouchEvent.TOUCH_BEGIN, OnTouchBegin, false, int.MAX_VALUE);
}
private function OnTouchBegin(e:TouchEvent):void
{
this.removeEventListener(TouchEvent.TOUCH_BEGIN, OnTouchBegin);
this.addEventListener(TouchEvent.TOUCH_END, OnTouchRelease, false, int.MAX_VALUE);
this.addEventListener(TouchEvent.TOUCH_OUT, OnTouchOut, false, int.MAX_VALUE);
}
private function OnTouchRelease(e:TouchEvent):void
{
this.addEventListener(TouchEvent.TOUCH_BEGIN, OnTouchBegin, false, int.MAX_VALUE);
this.removeEventListener(TouchEvent.TOUCH_END, OnTouchRelease);
this.removeEventListener(TouchEvent.TOUCH_OUT, OnTouchOut);
}
private function OnTouchOut(e:TouchEvent):void
{
this.addEventListener(TouchEvent.TOUCH_BEGIN, OnTouchBegin, false, int.MAX_VALUE);
this.removeEventListener(TouchEvent.TOUCH_END, OnTouchRelease);
this.removeEventListener(TouchEvent.TOUCH_OUT, OnTouchOut);
}
Then, when these buttons get hidden from the screen, a method is called to remove any of the listeners that are currently active on them:
public function Deactivate():void
{
this.removeEventListener(TouchEvent.TOUCH_OUT, OnTouchOut);
this.removeEventListener(TouchEvent.TOUCH_END, OnTouchRelease);
this.removeEventListener(TouchEvent.TOUCH_BEGIN, OnTouchBegin);
}
This is just for the standard button functionality (up/down texture and sound), on top of this, when I make the game, in my rollout class, I have an additional method that will add another event listener for custom logic that should occur when the button is touched (the button itself is created elsewhere).
public function AddRolloutButton(listener:Function):void
{
if (listener != null)
{
_buttons[index].addEventListener(TouchEvent.TOUCH_BEGIN, listener);
}
The buttons in the rollout itself are removed from the display list until they are to be shown. When the rollout is closed, the buttons are deactivated (removed from display list and the 3 button listeners within the button class are removed).
Everything works perfectly fine the very first time I open and close the rollout. After that, the event dispatching system just inexplicably dies. Every single InteractiveObject on the screen, regardless of position or type, becomes unusable. I traced out whether or not the listeners were still there on the rollout toggle button, and it was. I also confirmed that the rollout button itself was the only thing on the display list.
What I've noticed is that if I comment out the listener removal in the deactivate method of the button for the touch begin listener, or pass in null for the listener method in the AddRolloutButton method, everything works just fine. The issue seems to stem from having multiple listeners of the same type on the rollout buttons, and then removing one or all of them.
If anyone has any ideas of just what is going on, that would be very helpful. I was under the impression that adding multiple listeners of the same type to an InteractiveObject was perfectly valid.
UPDATE:
It appears that only TouchEvents get broken by this issue I'm having. I just tried using a mouse click listener on the stage after opening and closing the rollout, and that still works. So, only touch events are getting broken, if that helps at all.
Seems like there is something going wrong in your AddRolloutButton method. Are you sure you are assigning the correct listener function?
In your example the listener:Function argument should be equal to _buttons[index]. OnTouchBegin.
Or, since whatever class that owns the AddRolloutButton method seems to be in control of the buttons, you could potentially scrap the listener argument altogether since you know what method that needs to be triggered.
For example like this:
public function AddRolloutButton():void {
var currentButton:MyButtonClass = _buttons[index] as MyButtonClass;
currentButton.addEventListener(TouchEvent.TOUCH_BEGIN, currentButton.OnTouchBegin);
[...]
}
However, what you could do is to never remove the TouchEvent.TOUCH_BEGIN in the Deactivate function. The touch events will never be triggered when the DisplayObject isn't on the Display List. This means you don't have to worry about adding the listener every time you want to add the button to the Display List again.
If you set the listener to use a weak reference it will not hinder the button from being garbage collected when it's not needed anymore. To make your event listener use a weak reference, set the fifth argument of the addEventListener method to true.
addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void
public function Initialize():void {
this.addEventListener(TouchEvent.TOUCH_BEGIN, OnTouchBegin, false, int.MAX_VALUE, true);
}
Do you call the Initialize method again at some point after closing the rollout?
From your code it looks as though you remove all of the event listeners in Deactivate and then never add the TouchEvent.TOUCH_BEGIN listener again.
I'm not sure what you're trying to accomplish by removing the event listeners. Since the Button has a reference to the callback, it has a reference to that callback whether the listeners are attached or not. Are you thinking that adding a listener creates a reference from the callback to the button? It doesn't--the reverse is true.
If you really want to have the Button release the callback when it is removed from the display list, then it can't hold that reference after it removes the listeners. Consider using something like Supervising Presenter or a RobotLegs Mediator to manage those dependencies.
I seriously doubt that the entire event system is being borked by what you're doing.
I'd be more inclined to believe that this:
if (listener != null)
{
_buttons[index].addEventListener(TouchEvent.TOUCH_BEGIN, listener);
}
is failing, either because the button that's referenced is not the one that's actually on stage, or because listener is null..
I have seen times where adding and removing events with priorities can cause things to fail, but typically this is with events that aren't propagating on the display list.
One way that you can test this is simply to listen to the main document or the stage for touch events and see if you're getting those events. If the entire event system is borked, you won't get them, but if your listener logic is wrong, you will.
You may also want to check the willTrigger property on the button and event.
Here is my problem: I've got a swf loaed inside my loader an in that swf I have a keylistener:
stage.addEventListener(KeyboardEvent.KEY_DOWN, this.__onKeyDown, false, int.MAX_VALUE);
Now I'm adding a TextInput to this stage and I would like this input to catch all keyboard events while I'm focusing it. Is it possible to do so that native __onKeyDown will not fire until my TextInput has lost focus?
Thank you for your answers and sorry for my bad english.
You could give your listener higher priority (which you are), and stopAllPropogation in your handler. I've never tried this with an embedded swf so if it doesn't work right away, you could also try listening to the event in the capture phase (third parameter in addEventListener).
function __onKeyDown(e:KeyboardEvent):void {
e.stopImmediatePropagation();
//rest of you handler code here
}
It it possible to catch a double right click event in Actionscript 3?
It is with AIR. You can't capture RIGHT_CLICK in regular AS3, unfortunately.
There is, however, always the possibility of capturing right click events in JavaScript, and using ExternalInterface to call an event handler in the Flash program. See this blog, for example.
Actually you can catch RIGHT_CLICK at the moment :
You need player >11.2
Add additional compiler options -swf-version=19
Use this code :
stage.doubleClickEnabled = true;
stage.addEventListener(MouseEvent.RIGHT_CLICK, handler);
In handler you can save time of previous click, compare with second click and if it`s shorter than 0.5 seconds dispatch your own RIGHT_DOUBLE_CLICK event.