I'm working on an app in Lua + Corona. As a complete beginner, I've managed to hack together a little script for a carousel, but now I've got a question.
function forwardButtonPress()
if carousel.getCurImage() < #myImages then
carousel.slideToImage(carousel.getCurImage() + 1)
end
end
function backButtonPress()
if carousel.getCurImage() > 1 then
carousel.slideToImage(carousel.getCurImage() - 1)
end
end
--Here's where we do the actual initilization of the page.
local fwbutton = display.newImage("buttonArrow.png")
fwbutton.x = 260
fwbutton.y = 120
fwbutton:addEventListener("tap", forwardButtonPress )
local bkbutton = display.newImage("buttonBackArrow.png")
bkbutton.x = 60
bkbutton.y = 120
bkbutton:addEventListener("tap", backButtonPress )
If you look at the code, you'll see that I have two buttons, a back button and a forward one. Those are for sliding the images. So, say you get to the end of the carousel. The script takes care of making sure that it doesn't go past the end already, but how do I access the button to set the alpha to zero or fade it? It's linear, so I can't just put the button above its event function, so that the event function can reference the button... is there a way to pass the event function a reference to the button?
You can forward declare the event handler functions like this at the top of the file:
local forwardButtonPress
local backButtonPress
Then create your buttons and attach the event handlers (This is your code copied & pasted):
local fwbutton = display.newImage("buttonArrow.png")
fwbutton.x = 260
fwbutton.y = 120
fwbutton:addEventListener("tap", forwardButtonPress )
local bkbutton = display.newImage("buttonBackArrow.png")
bkbutton.x = 60
bkbutton.y = 120
bkbutton:addEventListener("tap", backButtonPress )
Add a function to manage setting the appearance of the buttons when either button is clicked:
local function setButtons()
if carosel.getCurImage() < #myImages then
fwbutton.alpha = 1.0
else
fwbutton.alpha = 0.5
end
if carosel.getCurImage() > 1 then
bkbutton.alpha = 1.0
else
bkbutton.alpha = 0.5
end
end
Now, you can write the function implementations, which will be able to deal with the buttons via the setButtons function:
forwardButtonPressed = function()
if carousel.getCurImage() < #myImages then
carousel.slideToImage(carousel.getCurImage() + 1)
end
setButtons()
end
backButtonPress = function()
if carousel.getCurImage() > 1 then
carousel.slideToImage(carousel.getCurImage() - 1)
end
setButtons()
end
Disclaimer: I'm not able to test this now, so there might be a syntax error somewhere, but organizing the code this way will work for what you're doing.
You can create/define the buttons above the function, and attach the EventListener below, no? If not, I don't really understand the problem.
Related
frame.buttons = {}
frame.AddButton = function()
frame.buttons[#frame.buttons + 1] = frame:Add("DButton")
local button = frame.Buttons[#frame.buttons]
end
I know it's simple, but it's the only part so far that I do not understand.
How do you add now buttons and how do you access them?
This code adds a button to a Frame instance. It also creates a list of buttons in that Frame. You need to replace that "DButton" by a DButton instance.
Ideally you change the code like that:
frame.buttons = {}
frame.AddButton = function(button)
frame.buttons[#frame.buttons + 1] = frame:Add(button)
local button = frame.Buttons[#frame.buttons]
end
If you want to add a button, create it, then call frame.AddButton(myButton).
I have this script in a brick:
local giver = 1
function onClicked()
game.Players.[I NEED THE PLAYER NAME HERE].leaderstats.Clicks.Value = game.Players.[I NEED THE PLAYER NAME HERE].leaderstats.Clicks.Value + giver
end
script.Parent.ClickDetector.MouseClick:connect(onClicked)
Now I need to somehow get the player's name that clicked it and put it where I need to.
The ClickDetectors's MouseClick event have the "Clicking Player" as parameter, so you can do it like this:
local giver = 1
function onClicked(Player)
Player.leaderstats.Clicks.Value = Player.leaderstats.Clicks.Value + giver
end
script.Parent.ClickDetector.MouseClick:connect(onClicked)
However, this requires the FilteringEnabled to be set to false (not recomended).
To solve this, make a LocalScript in the brick with the code:
script.Parent.ClickDetector.MouseClick:connect(function(Player)
game.ReplicatedStorage:WaitForChild("BrickClick"):InvokeServer(script.Parent)
end)
And in a Script placed in the ServerScriptService put:
local Listener = game.ReplicatedStorage:FindFirstChild("BrickClick")
if Listener == nil then
Listener = Instance.new("RemoteFunction")
Listener.Name = "BrickClick"
Listener.Parent = game.ReplicatedStorage
end
function Listener.OnServerInvoke(Player,Brick)
Player.leaderstats.Clicks.Value = Player.leaderstats.Clicks.Value + 1
end
I won't point you to the wiki page for further reading, even thought it contains a bit of what you need, it contains too little information.
The ClickDetector's MouseClick info, the guide about FilteringEnabled and the guide about RemoteFunctions are better.
Try this!
script.Parent.MouseClick:Connect(function(Player)
-- Kill The Player
-- The parameter is referring to game.Players So if you want to do a kill button use .Character
Player.Character:BreakJoints()
-- Change The Color To Red (Other details)
script.Parent.Parent.BrickColor = BrickColor.new("Really red")
script.Parent.MaxActivationDistance = 0
-- Wait 4 Secs
wait(5)
-- Change The Color To Green
script.Parent.Parent.BrickColor = BrickColor.new("Lime green")
script.Parent.MaxActivationDistance = 50
end)
I have a model called door
Inside I have a BoolValue named Open
I have a model called Top that has all of the door blocks named Work Mabey Comeon and Proboblynot
And I have Block that when touched is supposed to make Top move up
Directly inside door I have this script
door = script.Parent
open = door.Open
Top = door.Top
opener = 18
speed = 100
steps = speed
startl = Top.CFrame
function MoveDoorToCFrame(cfrm,dr)
dr.Work.CFrame = cfrm
dr.Mabey.CFrame = dr.Work.CFrame * CFrame.new(0,-7.2,0)
dr.Comeon.CFrame = dr.Work.CFrame * CFrame.new(0,10.8,0)
dr.Problynot.CFrame = dr.Work.CFrame * CFrame.new(0,10.8,0)
end
function Update()
if speed/steps < 0.5 then
calc = 1-math.cos(math.rad((-90/speed)*steps*2))
else
calc = 1+math.sin(math.rad((90/speed)*((speed/2)-steps)*2))
end
MoveDoorToCFrame(startl * CFrame.new(0,(calc/2)*opener,0),Top)
end
Update()
while true do
wait()
if not open.Value and steps < speed then
steps = steps + 1
Update()
elseif open.Value and steps > 0 then
steps = steps - 1
Update()
end
end
Inside the button that is supposed to activate on touch I have
script.Parent.Touched:connect(function()
script.Parent.Parent.Open.Value = not script.Parent.Parent.Open.Value
end)
script.Parent.Parent.Open.Changed:connect(Update)
Update()
If you know how to fix this it would be gladly appreciated.
Update November 2015:
Using PrimaryPart
Since writing this post, ROBLOX has changed a lot in regards to the API. To move a model like requested, you should set the PrimaryPart property of the model to a central part inside the model. This will act as the origin for the model's movements.
You can then use model:SetPrimaryPartCFrame(cframe) to set the CFrame of the model. You can also retrieve this property by using model:GetPrimaryPartCFrame(), although I believe that is just a shortcut method for model.PrimaryPart.CFrame.
In code, it would look like this:
-- Set PrimaryPart:
MODEL.PrimaryPart = MODEL.SomeCentralPart
...
-- CFrame movement:
local movement = CFrame.new(0, 10, 0)
-- Move the model:
MODEL:SetPrimaryPartCFrame(MODEL:GetPrimaryPartCFrame() * movement)
Option A: Use Model's methods
I think you are making this much more difficult than it needs to be. Whenever you run into an issue like this, be sure to check the current APIs provided. The ROBLOX Model object contains a nifty method called 'TranslateBy' which takes a Vector3 argument to translate the model.
Using MODEL:TranslateBy(Vector3) is similar to moving a model via CFrame, since it ignores collisions.
Another alternative is MODEL:MoveTo(Vector3) which moves a whole model to the given Vector3 world position. The downside to this is that it does collide.
One way to get the same MoveTo effect but without collisions can be done with the TranslateBy method:
MODEL:TranslateBy(Vector3Position - MODEL:GetModelCFrame().p)
Option B: Write a custom function to manipulate the model's CFrame
Another alternative would be to manipulate the whole model's CFrame entirely. To do this, you can write a clever function that will move a whole model relative to an 'origin' point. This is similar to moving shapes on a grid given their points and an origin, except in three dimensions. Using ROBLOX's built-in functions, this is much easier though.
A good way to do this would be to write a function that lets you actually assign a CFrame value to a whole model. Another way would be to allow a translation via CFrame too.
Here's an example:
function ModelCFrameAPI(model)
local parts = {} -- Hold all BasePart objects
local cf = {} -- API for CFrame manipulation
do
-- Recurse to get all parts:
local function Scan(parent)
for k,v in pairs(parent:GetChildren()) do
if (v:IsA("BasePart")) then
table.insert(parts, v)
end
Scan(v)
end
end
Scan(model)
end
-- Set the model's CFrame
-- NOTE: 'GetModelCFrame()' will return the model's CFrame
-- based on the given PrimaryPart. If no PrimaryPart is provided
-- (which by default is true), ROBLOX will try to determine
-- the center CFrame of the model and return that.
function cf:SetCFrame(cf)
local originInverse = model:GetModelCFrame():inverse()
for _,v in pairs(parts) do
v.CFrame = (cf * (originInverse * v.CFrame))
end
end
-- Translate the model's CFrame
function cf:TranslateCFrame(deltaCf)
local cf = (model:GetModelCFrame() * deltaCf)
self:SetCFrame(cf)
end
return cf
end
-- Usage:
local myModel = game.Workspace.SOME_MODEL
local myModelCF = ModelCFrameAPI(myModel)
-- Move to 10,10,10 and rotate Y-axis by 180 degrees:
myModelCF:SetCFrame(CFrame.new(10, 10, 10) * CFrame.Angles(0, math.pi, 0))
-- Translate by 30,0,-10 and rotate Y-axis by 90 degrees
myModelCF:TranslateCFrame(CFrame.new(30, 0, -10) * CFrame.Angles(0, math.pi/2, 0))
This might be hard.
You might want to look to free models for this one unless the people above get it to work.
I, however, do have a script to move a model:
game.Workspace.Model:MoveTo(Vector3.new(0,0,0))
Your code indeed needs fixing.
You should NOT use a never-ending loop to make your stuff work (unless that is the only way).
You should rather base actions on events.
Consider to use this:
Structure:
Door [Model]
DoorScript [Script]
Button [Part]
DoorOpen [BoolValue]
Top [Model]
Mabey [Part]
Comeon [Part]
Problynot [Part]
DoorScript:
local Model = script.Parent
local Door = Model.Top
local Button = Model.Button
local DoorOpen = Model.DoorOpen
local Offset = 0
local ToOffset = 100
local Direction = 1
local StepLength = 0.1
local Moving = false
function StartMoving()
if Moving then return end
Moving = true
while (DoorOpen.Value and Offset ~= ToOffset) or (not DoorOpen.Value and Offset ~= 0) do
local Change = Offset
Offset = math.max(0,math.min(ToOffset,Offset + StepLength * (DoorOpen.Value and 1 or -1)))
Change = Offset - Change
Top:TranslateBy(Vector3.new(0,Change,0))
wait()
end
Moving = false
end
StartMoving()
DoorOpen.Changed:connect(StartMoving)
local Debounce = false
Button.Touched:connect(function()
if Debounce then return end
Debounce = true
DoorOpen.Value = not DoorOpen.Value
wait(4)
Debounce = false
end)
You might want to adjust the speed tho.
This can be used to move models, try adding something like this into your code. It's more dynamic.
a = Workspace.Model
for i=0.1,40 do
for i,v in pairs(a:getChildren()) do
if v:IsA("Part") then
v.CFrame = CFrame.new(v.CFrame + Vector3.new(0,0.1,0))
else print("Not a part")
end
end
end
I want to create a table with display Objects on specific positions. I wrote the following
for i=0, 5 do
life[i] = display.newImage( "life.png" )
end
but when I am trying this:
for i=0, 5 do
life[i] = display.newImage( "life.png" )
life[i].x=i*Space_
end
compiler complains attemp to index field ? nil value
Any idea why this happen or how can I solve it? I want to use a for loop to add objects in a table (or maybe group? ) on specific positions.
Show us where Space_ is in your code.
Try this:
local SpaceX = 10
for i=0, 5 do
life[i] = display.newImage( "life.png" )
life[i].x = i * SpaceX
end
Corona doesn't find your image and returns nil as the result of display.newImage call. When you try then to access field x of a nil value, you get the error.
Make sure your image is available to your script.
This assert should probably trigger, because life.png could not be found
for i=0, 5 do
life[i] = assert(display.newImage("life.png"), "image could not be found")
life[i].x=i*Space_
end
I'm trying a GTween example from the following link
Gideros GTween with Easing
The example doesn't work out of the box, so I dug into the source code of GTween and added the following lines to my example in order to allow event dispatching.
local tween = GTween.new(jewel, 2, animProperties, gtweenProperties)
tween.suppressEvents = false -- New Line #1
tween.dispatchEvents = true -- New Line #2
tween:addEventListener('complete', function()
stage:removeChild(jewel)
jewel = nil
end)
However, the app crashes. I tried commenting the following line in gtween.lua
self:dispatchEvent(Event.new(name))
and the app doesn't crash, however the callbacks aren't invoked (obviously, why would it?)
This is the stack trace from the app.
gtween.lua:445: attempt to call method 'dispatchEvent' (a boolean value)
stack traceback:
gtween.lua:445: in function 'dispatchEvt'
gtween.lua:255: in function 'setPosition'
gtween.lua:86: in function <gtween.lua:74>
Any pointers would be greatly appreciated. Thanks.
PS: I'm not sure if this is a bug on Gideros.
i just tried with the latest gideros' gtween (note that it is edited 10 days ago), and use this sample (i took the sample from your link and add sprite definition, also include a image file in project) and it works(the callback is called) :
local animate = {}
animate.y = 100
animate.x = 100
animate.alpha = 0.5
animate.scaleX = 0.5
animate.scaleY = 0.5
animate.rotation = math.random(0, 360)
local properties = {}
properties.delay = 0
properties.ease = easing.inElastic
properties.dispatchEvents = true
local sprite = Bitmap.new(Texture.new("box.png")) -- ADD THIS
stage:addChild(sprite) -- ADD THIS
local tween = GTween.new(sprite, 10, animate, properties)
tween:addEventListener("complete", function()
stage:removeChild(sprite)
sprite = nil
end)