@Naomi,

Setting focus to nil doesn't stop the event. All it does is allow other objects to get the touch event if the touch moves off the object. If you setFocus to nil and you move off the object, it will never receive a ended event for that object.

The best way to handle the problem is keep the focus on the object (so you get an ended event) and set a custom flag in the object so you can ignore the moved events. You clear the focus on the ended event.

@Tom, thank you so much for the advice and detailed explanation as to what happens when the setFocus is nilled.

I'd like to know if there's a harm in not reaching the ended event. When I set setFocus to nil, I also trigger things that should happen when the touch reaches "end" (or "cancelled") state. It appears that the same object can be touched again and respond to "began" phase (but I need to test this thoroughly to ensure it does.) If the object can be touched again, and can trigger "began" phase without an issue, nilling focus would be a real good solution for me. Hmmm... when the object is touched again, does it trigger "cancelled" event from the previous touch? If it does, this is actually the most perfect solution for me.

What I'm trying to address is a bug that isn't too easy to reproduce, but can happen every now and then. The problem is, even when the finger is lifted off the screen (and off of the object), my game sometimes does not register that the touch event has ended. When this happens, the game eventually comes to a freezing point. Hard exit is the only option at that point.

In fact, if there's a way to tell the game that the touch is cancelled upon specific flag/trigger and properly reaches the "cancelled" state even when finger is still touching the object, that would help me set up a very good work around to my problem. (And nilling focus appears to work the way I hoped it would so far.)

That said, the best solution would be, for the device/simulator to always and accurately detect the end of the touch event. If it can truly reach the end state when nothing is touching the screen, I wouldn't have to find the workaround to force the cancellation event.

Is there a built in function that I can fire off to force the object to register the fact the touch has already been ended? When the screen is no longer being touched, I really want my object to register that it is not being touched....

Naomi

I'm trying something similar but if you drag and run into something you probably should be able to go the other direction in the same move so I'm thinking I dont need to stop the event as much as prevent teleports

Rob

@robmiracle and @Naomi,

When you wish to cancel the touch (object collides with something or whatever), have you tried using the "dispatchEvent()" command to "force send" and "ended" phase to the object? If you haven't used this command before or aren't too familiar with it (I think alot of people aren't even aware that it exists), it's one of the rare Corona gems that can solve a multitude of issues with one line. Basically, you can "send" any event of any type(name) to an object that has a listener. Furthermore, you're not even limited by Corona's built-in parameters; you can even do something like this:

obj:dispatchEvent( { name="touch", phase="off" } )

You'll notice that "off" is not a standard Corona touch phase condition, but you can still send it and listen for that value in the object's listener routine... or you can, obviously, send a standard phase value like "ended" and Corona will treat that exactly the same as if the user's finger lifted off the screen.

Another example with even more customization...

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local function myListener( event )
  if ( event.condition = "stop" ) then
    --do something!
  end
end
 
local obj = --(display object, i.e a button)
obj:addEventListener( "tap", myListener )
obj:dispatchEvent( { name="tap", target=obj, condition="stop" } )