Hi,
I have a scene where initial variables are set in the beginning and then changed throughout the script and in modules. I know that once Corona creates a scene and goes to another, it keeps the old scene in memory for performance reasons.
However, when I get back to this scene it doesn’t function as expected because none of the variables are what they are initially supposed to be. How should I go about this? How do you guys handle this problem?
Thanks in advance.
Don’t use create(), use show, will phase instead.
Destroy and reset the scene in hide, did phase.
See example #12 in here:
https://github.com/roaminggamer/CoronaGeek/raw/master/Hangouts/composer_scene_manager.zip
I know @roaminggamer and I differ in opinion on this. But you should use scene:create() to create all objects that are for the scene that are created before game play. If you’re spawning enemies, you shouldn’t do that when ready.
Because Lua does not re-execute the outermost chunk of code after the initial load, you can’t put something like:
local score = 0
and expect score to change when you go back to that scene. The proper way, as @roaminggamer pointed out is to use scene:show()'s “will” phase to reposition all moved objects back to their baseline, reset values like your score to 0. However this takes quite a bit of work to get everything. Most developers will go the route of using a cut scene and during that cut scene, remove the game scene before going back. That scene removal will cause the outer chunk to re-execute like coming back to the scene the first time.
Rob
I agree that create() should create objects (and destroy() should remove them).
Personally, I would create functions like initLevel() or whatever to “start” or “restart” the level. This could be called from show() or from a custom start point.
Not sure if this is covered in a tutorial or not but if not it should be - as cut scenes add additional unload/reload overhead that is really not required.
Not meaning to hijack here… but @rob I would appreciate some Corona input to my post of 2 days ago that seems to have been missed. Thanks
Done!
Thanks for all the feedback guys!
I rather not use the cut scene method. The thing is, I alter these variables inside modules where there is no show() happening but I did end up creating an init() function in the modules that needed it and then I called those init functions from the main scene. I’ll make sure to call init in the show() function.
Thanks again!
Ps. I’m finding that many times when I create a runtime listener or a new timer, I always need to make sure to cancel them or remove them when leaving the scene. It would be a nice feature if Corona handled all that when a scene is to be destroyed, it would just cancel all timers and remove all listeners that were created in that scene. Just a thought.
Or add a reset() function to each module.
Rob
Don’t use create(), use show, will phase instead.
Destroy and reset the scene in hide, did phase.
See example #12 in here:
https://github.com/roaminggamer/CoronaGeek/raw/master/Hangouts/composer_scene_manager.zip
I know @roaminggamer and I differ in opinion on this. But you should use scene:create() to create all objects that are for the scene that are created before game play. If you’re spawning enemies, you shouldn’t do that when ready.
Because Lua does not re-execute the outermost chunk of code after the initial load, you can’t put something like:
local score = 0
and expect score to change when you go back to that scene. The proper way, as @roaminggamer pointed out is to use scene:show()'s “will” phase to reposition all moved objects back to their baseline, reset values like your score to 0. However this takes quite a bit of work to get everything. Most developers will go the route of using a cut scene and during that cut scene, remove the game scene before going back. That scene removal will cause the outer chunk to re-execute like coming back to the scene the first time.
Rob
I agree that create() should create objects (and destroy() should remove them).
Personally, I would create functions like initLevel() or whatever to “start” or “restart” the level. This could be called from show() or from a custom start point.
Not sure if this is covered in a tutorial or not but if not it should be - as cut scenes add additional unload/reload overhead that is really not required.
Not meaning to hijack here… but @rob I would appreciate some Corona input to my post of 2 days ago that seems to have been missed. Thanks
Done!
Thanks for all the feedback guys!
I rather not use the cut scene method. The thing is, I alter these variables inside modules where there is no show() happening but I did end up creating an init() function in the modules that needed it and then I called those init functions from the main scene. I’ll make sure to call init in the show() function.
Thanks again!
Ps. I’m finding that many times when I create a runtime listener or a new timer, I always need to make sure to cancel them or remove them when leaving the scene. It would be a nice feature if Corona handled all that when a scene is to be destroyed, it would just cancel all timers and remove all listeners that were created in that scene. Just a thought.
Or add a reset() function to each module.
Rob