Corona SDK Using nativ text field in storyboard - sdk

Question

So, I have a program that is using the corona storyboard.
There is scene 1 where the user can type something in a textbox at and there is also another scene, scene 2 where I have some text. The problem is that when the user goes away from the scene with the textbox, the textbox still appears on the screen. I've tried using removeSelf() which does delete it. But the problem is that the textbox is gone forever if i use removeSelf(), even when the user goes back to scene 1, it's still gone!
How could I fix this? Here is the code for scene 1:
--
-- view1.lua
--
-----------------------------------------------------------------------------------------
local storyboard = require( "storyboard" )
local scene = storyboard.newScene()
function scene:createScene( event )
local group = self.view
local bg = display.newRect( 0, 0, display.contentWidth, display.contentHeight )
bg:setFillColor(0,255,0 ) -- green
local title = display.newText( "Second View", 0, 0, native.systemFont, 32 )
title:setTextColor( 0 ) -- black
title:setReferencePoint( display.CenterReferencePoint )
title.x = display.contentWidth * 0.5
title.y = 125
local summary = display.newText( "Loaded by the first tab 'onPress' listener\n— specified in the 'tabButtons' table.", 0, 0, 300, 300, native.systemFont, 14 )
summary:setTextColor( 0 ) -- black
summary:setReferencePoint( display.CenterReferencePoint )
summary.x = display.contentWidth * 0.5 + 10
summary.y = title.y + 215
local function textListener( event )
if ( event.phase == "began" ) then
-- user begins editing text field
print( event.text )
elseif ( event.phase == "ended" ) then
-- text field loses focus
elseif ( event.phase == "ended" or event.phase == "submitted" ) then
-- do something with defaulField's text
elseif ( event.phase == "editing" ) then
print( event.newCharacters )
print( event.oldText )
print( event.startPosition )
print( event.text )
end
end
-- Create our Text Field
defaultField = native.newTextField( 150, 150, 180, 30 )
defaultField:addEventListener( "userInput", textListener )
-- all objects must be added to group (e.g. self.view)
group:insert( bg )
group:insert( title )
group:insert( summary )
end
-- Called immediately after scene has moved onscreen:
function scene:enterScene( event )
local group = self.view
-- do nothing
end
-- Called when scene is about to move offscreen:
function scene:exitScene( event )
local group = self.view
-- INSERT code here (e.g. stop timers, remove listenets, unload sounds, etc.)
end
-- If scene's view is removed, scene:destroyScene() will be called just prior to:
function scene:destroyScene( event )
local group = self.view
-- INSERT code here (e.g. remove listeners, remove widgets, save state variables, etc.)
end
-----------------------------------------------------------------------------------------
-- END OF YOUR IMPLEMENTATION
-----------------------------------------------------------------------------------------
-- "createScene" event is dispatched if scene's view does not exist
scene:addEventListener( "createScene", scene )
-- "enterScene" event is dispatched whenever scene transition has finished
scene:addEventListener( "enterScene", scene )
-- "exitScene" event is dispatched whenever before next scene's transition begins
scene:addEventListener( "exitScene", scene )
-- "destroyScene" event is dispatched before view is unloaded, which can be
-- automatically unloaded in low memory situations, or explicitly via a call to
-- storyboard.purgeScene() or storyboard.removeScene().
scene:addEventListener( "destroyScene", scene )
-----------------------------------------------------------------------------------------
return scene

Answer 1

So maybe you could use alpha to hide all elements in group?
group.alpha=0

Answer 2

You need to add the text box on the scene:enterScene method and remove it on the scene:exitScene.
Corona calls createScene only once, when creating the scene, but it calls enterScene and exitScene when the scene moves in or out of the stack. These are the places to create/remove elements.
For more information about screen management in corona you can read this. It's main focus is about cleaning up resources used in a scene and the examples are about sounds, but it applies to what you're trying to do and explains a little the Scene Management in Corona.