Corona always display a black screen in the build - coronasdk

I'm trying to make a build with Corona for Android devices.
Is a very simple app, only use a reference to de 'ui'
local ui = require("ui");
local btnright = ui.newButton{
defaultSrc = "button-right.png",
defaultX = 100,
defaultY = 100,
overSrc = "button-right-over.png",
overX = 100,
overY = 100,
onEvent = buttonHandler,
id = "btn-right"
}
But, when I generate the apk, only display me a black screen and in the simulator shows me the button

in android when naming the file or the image you must not use special character it must only contain [a-z0-9_.] and no capital letters too. you can see the widget button on corona simulator because simulator can read special character.
for more details about resource names refer to this link
and change your widget name from:
local ui = require("ui");
local btnright = ui.newButton{
defaultSrc = "button-right.png",
defaultX = 100,
defaultY = 100,
overSrc = "button-right-over.png",
overX = 100,
overY = 100,
onEvent = buttonHandler,
id = "btn-right"
}
to this
local ui = require("ui");
local btnright = ui.newButton{
defaultSrc = "button_right.png",
defaultX = 100,
defaultY = 100,
overSrc = "button_right_over.png",
overX = 100,
overY = 100,
onEvent = buttonHandler,
id = "btn-right"
}

Which version of corona are you using?
Why not try the widget.newButton()?
check this out. http://docs.coronalabs.com/api/library/widget/newButton.html

Capital letters are allowed. I'm not sure about hyphens, but they are valid characters in Linux and Unix (the core OS used by Android and iOS) However what is likely the cause is case sensitivity. Devices like Android and iOS are case sensitive. The simulator is not, so if you have a button named:
button-right.png
And the actual file name is:
Button-right.PNG
it won't match and it will generate an error. You need to tether your device to your computer and view the device's console log. If you do not know how to do that please see this blog post:
http://www.coronalabs.com/blog/2013/07/09/tutorial-basic-debugging/

Related

Corona SDK - display.newtext with options table returns error

my code is:
local options =
{
--parent = textGroup,
text = "Hello World",
x = 100,
y = 200,
width = 128, --required for multi-line and alignment
font = native.systemFontBold,
fontSize = 18,
align = "right" --new alignment parameter
}
local test = display.newText(options)
But it returns:
bad argument #-1 to 'newText' (Proxy expected, got nil)
Does anybody know why this happens?
Thank you
Maybe you are using old Corona SDK version which does not have newText with options table?
The code that you put it is fine. your error, maybe is on another line. look this post here
it is similar to error that you have. However It is a good information.
I hope that this help you.

MapView to background - Corona SDK

I need some help with the MapView in Corona SDK. I want to put the map as background (but with all functions) and, in this case, a button to the front. Here is my code:
function scene:createScene( event )
local group = self.view
if ( system.getInfo( "environment" ) == "simulator" ) then
local simulatorMessage = "Maps not supported in Corona Simulator.\nYou must build for iOS or Android to test native.newMapView() support."
local label = display.newText( simulatorMessage, 36, 40, 270, 0, native.systemFont, 12 )
label.anchorX = 0
label.anchorY = 0
end
myMap = native.newMapView( 20, 20, display.contentWidth, display.contentHeight )
if ( myMap ) then
myMap.mapType = "normal"
myMap.x = display.contentCenterX
myMap.y = display.contentCenterY
myMap:setCenter( currentLatitude, currentLongitude )
myMap:addEventListener("mapLocation", mapLocationListener)
end
backBtn = widget.newButton
{
id="backButton",
label="Back",
fontSize="30",
labelColor={ default={1, 1, 1}, over={0, 0, 0, 0.5} },
defaultFile="images/button.png",
width = dispWidth * 0.25, height = dispHeight * 0.1,
onRelease = onBackBtnRelease
}
backBtn.anchorX = 0.5
backBtn.anchorY = 0.5
backBtn.x = display.contentWidth * 0.8
backBtn.y = dispHeight * 0.8
backBtn:toFront()
group:insert( backBtn )
group:toFront() --second try to put that button to front
end
Since the MapView is a native object I can't add it to any group and 'mapView:toBack()' doesn't work as well ('attempt to index upvalue 'myMap' (a nil value)'). In Corona SDK the button appears without the map, as expected. On device I get the map without my button, not as expected.
Is it any possible to put a native object to the back, or to force something to be in the front?
What you are trying to do with the map and the button is not currently possible with CoronaSDK.
Indeed the MapView is a native object. According to Corona's documentation, you cannot place other objects on top of a MapView.
The documentation says:
Map objects, like other native display objects, cannot be inserted into groups and are always displayed on top of regular Display Objects (groups, vector, images, and text).
See documentation here
Good luck coding.
First Check the Following :
If button doesn't appear on device most common problem will be , you might misspell the Image names(Check for Caps) or check the path of the file is proper or not.
To know in detail about the mapView : http://docs.coronalabs.com/api/library/native/newMapView.html
I know you might have visited already, its better you look again.
Thanks,

Corona SDK display.remove() in lua

this code (lua) gives you a random value from the table "local a" by pressing the text "new". Unfortunately the new random value just appears above the old one. I've tried to remove the old value e.g. with display.remove(mmDis), but it doesn't work.
The second problem is that sometimes I also get back the value "nil" and not only the four entries from the table.
Both things must be easy to solve, but as newbie to lua and working on these small things for almost 4 hours now I just don't get what to change to make it work.
-- references
local mmDis
-- functions
function randomText(event)
display.remove(mmDis)
local a = {"Banana!","Apple!","Potato","Pie"}
com = (a[math.random(0.5,#a)])
local mmDis = display.newText(tostring(com),
display.contentWidth*0.57, display.contentHeight*0.7,
display.contentWidth*0.9, display.contentHeight*0.8, "Calibri", 60)
end
-- menu button
local textnew = display.newText("New", 0, 0, "Calibri", 40)
textnew.x = display.contentWidth*0.2
textnew.y = display.contentHeight*0.9
textnew:addEventListener ("tap", randomText )
It's hard to understand what you are trying to do because when you create textnew you have it in one position and size, while in randomeText() you seem to want to replace that text object with a new one, but you put it at a different pos and size. It appears you want to change the object's text every time you press on tap; in this case, you don't need to replace the text object, you just replace its text.
Also:
you have two "local mmDis", the second one will hide the first, not sure what you're after there
read carefully the docs for math.random
com is already a string so you don't need tostring
Try this code and let me know if this is not what you are after:
local menuTextOptions = {
text = "New",
x = display.contentWidth*0.2,
y = display.contentHeight*0.9,
align = 'left',
font = "Calibri",
fontSize = 40,
}
local textnew = display.newText(menuTextOptions)
-- functions
function randomText(event)
local a = {"Banana!","Apple!","Potato","Pie"}
local com = a[math.random(1,#a)]
textnew.text = com
-- if you want to change position too:
-- textnew.x = display.contentWidth*0.2
-- textnew.y = display.contentHeight*0.9
-- if you want to change size too, but only used for multiline text:
-- textnew.width = display.contentWidth*0.9
-- textnew.height = display.contentHeight*0.8
end
textnew:addEventListener ("tap", randomText )
Sometimes it looks like the button doesn't do anything when you tap but that's because the random number happens to be same as previous, you could put a loop to guard against that. Ig you actually want to change the pos and/or width, then the above code makes it clear where you should do that.
So, that's the basic code (without any extras at the moment :)) how it should be. Big thanks to Scholli!:
local menuTextOptions = {
text = "New",
x = display.contentWidth*0.2,
y = display.contentHeight*0.9,
align = 'left',
font = "Calibri",
fontSize = 40,
}
local textnew = display.newText(menuTextOptions)
local replacement = display.newText(menuTextOptions)
replacement.y = display.contentHeight*0.5
-- functions
function randomText(event)
local a = {"Banana!","Apple!","Potato","Pie"}
local com = a[math.random(1,#a)]
replacement.text = com
end
textnew:addEventListener ("tap", randomText )

Lua - Corona SDK - Text not appearing inside a display Object

I am trying to move a display object that is hiding over the right side of the screen, into the scene. It works wonderfully with images (i.e. the background), but not with texts (the coords seem correct from debugging them with print(), but they never display, I already tried the obj:toFront).
I thought that they may work inside display objects, so I put everything in a display Object: Nothing. Just the text? Neither. Anyone knows why/how to override this?
function tscreen:init()
local textGroup = display.newGroup()
local menuBackground = self:getBtn("src/bgMenu.png")
menuBackground.isVisible = false
menuBackground.anchorX = 0.5
menuBackground.anchorY = 0.5
self.menuBackground = menuBackground
local optionsText = {
parent = textGroup,
text = "Hello World",
x = centerX,
y = centerY,
width = 128,
font = native.systemFontBold,
fontSize = 14,
align = "center"
}
local workText = display.newText( optionsText )
workText:setFillColor( 1, 0, 0 )
setPos(textGroup, W, 0)
--setPos() is a custom function that assigns x and y coords
textGroup.isVisible = false
self.textGroup = textGroup
end
function tscreen:show()
local menuBackground = self.menuBackground
local textGroup = self.textGroup
local inTime = 1200
setPos(menuBackground, 2*W + centerX, centerY)
menuBackground.isVisible = true
setPos(textGroup, W, 0)
textGroup.isVisible = true
self:cancelTween(menuBackground)
self:cancelTween(textGroup)
menuBackground.tween = transition.to(menuBackground, {time = inTime, transition = easing.outExpo, x = centerX,
onComplete = function()
tscreen:cancelTween(menuBackground)
end
})
textGroup.tween = transition.to(textGroup, {time = inTime, transition = easing.outExpo, x = 0,
onComplete = function()
tscreen:cancelTween(textGroup)
print(getPos(textGroup), textGroup.width, textGroup.height)
end
})
end
I have the starters edition of Corona, so I don't have the recently implemented Composer API.
Maybe this isn't the most appropriate site to post this query since there already is a Corona SDK forum, but I'm trying anyway.
I'm not seeing anything wrong, but a group should not be necessary. Verify that the text can be seen ever: in the init(), do
local optionsText = {
text = "Hello World",
x = 0,
y = 100,
}
local workText = display.newText( optionsText )
workText:setFillColor( 1, 1, 1 )
If you can't see the text then something else is going on, maybe your init() is not being called or such. Once you see it, change the parameters to what you want (fill color etc), and test. If still works, add a transition, right after, in the init():
local easeXto100 = {
time = 2000,
transition = easing.outExpo,
x = 100,
onComplete = function() print('did you see text move from x=0 to 100?') end
}
transition.to(workText, easeXto100)
If you see it move, then move the relevant parts of code to your show(), if now it disappears this will give you clue.

Character Selection in Corona SDK

I make an endless run game using Corona SDK and I need to make a character selection between 2 characters (boy/girl). I don't have any idea how I should start.
I tried to make 2 portraits of the character on the menu screen, but I don't know what to do on Event Touch on them. I tried to save them in a variable but I don't know how to load them in the game.lua. There I have:
local spriteSheet = sprite.newSpriteSheet("monsterSpriteSheet.png", 100, 100)
local monsterSet = sprite.newSpriteSet(spriteSheet, 1, 7)
sprite.add(monsterSet, "running", 1, 6, 600, 0)
sprite.add(monsterSet, "jumping", 7, 7, 1, 1)
local monster = sprite.newSprite(monsterSet)
monster:prepare("running")
monster:play()
monster.x = 60
monster.y = 200
monster.gravity = -6
monster.accel = 0
monster.isAlive = true
I've got a main.lua a menu.lua and a game.lua. I use director class for transition. Any ideas on how I can do this?
You can pass parameters through storyboard.gotoScene
local options = {
effect = "crossFade",
time = 500,
params = {
character = myCharacter,
}
}
storyboard.gotoScene( "game", options )
and in the game.lua
function scene:createScene( event )
local params = event.params
local character = params.character
end
You could also create a data file and point to that file.
For example:
data.lua
local data = {}
return data
Then in your selection scene require data.lua and save your chosen character to it.
data.chosenCharacter = chosenCharater
Then in your game scene require data.lua again and point your character to what is saved in data.
local character = data.chosenCharacter

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