How to make movement buttons work with events

Zizanyman

I am making a game with three buttons to control a rocket. They are left, right and shoot (the screenshot is attached). However, I can't figure out how to get the movement to work. With my current method, whenever you lift any finger off the screen, it stops the ship entirely. This is bad if you tap left, then right, then release your finger off of left (or vice versa), because it should just keep moving to the right. Instead, the ship stops moving (. It also happens when you press the fire button, once you release your finger, the ship just stops. Here is my code (I haven't programmed in the firing yet):

function game:onEnterFrame()   if MoveLeft == true then Ship:setPosition(Ship:getX()-2,Ship:getY()) Ship:setRotation(-30) end if MoveRight == true then Ship:setPosition(Ship:getX()+2,Ship:getY()) Ship:setRotation(30) end if MoveLeft == false and MoveRight == false then Ship:setRotation(0) end end   function game:MoveShip(event)   if Left:hitTestPoint(event.touch.x,event.touch.y) then MoveLeft = true MoveRight = false end if Right:hitTestPoint(event.touch.x,event.touch.y) then MoveRight = true MoveLeft = false end if Fire:hitTestPoint(event.touch.x,event.touch.y) then print("fire") end end   end   function game:StopShip(event)   if MoveLeft == true then MoveLeft = false end if MoveRight == true then MoveRight = false end   end

Does anybody know how to fix this issue?

keszegh

well so far it's not clear. probably you call StopShip somewhere else which stops the movement.

Zizanyman

I know why it's stopping it, I just don't know how to work around it. The reason is that when I put my finger on left, MoveLeft becomes true, but when I put my finger on right, MoveRight becomes true. In my StopShip function, which is called when you release your finger (event listener), it thinks that because MoveRight = true that it should make it false, which in turn stops the ship.

Zizanyman

Just in case it helps, here are the event listeners I have in my init function:

self:addEventListener(Event.TOUCHES_BEGIN,self.MoveShip,self) self:addEventListener(Event.TOUCHES_END,self.StopShip,self) self:addEventListener(Event.ENTER_FRAME,self.onEnterFrame,self)

pie

@Zizanyman if you're right it just needs to know when to set the MoveLeft/Right to false, according to the button that has been released. Maybe you could save this info somewhere and check it in stopShip()
Another option could be to check the hitTestPoints of the buttons directly in enterframe and act accordingly.

If you can share your project I will try to make it work but I am too tired to setup a dummy project to make a test right now

keszegh

you could add checking which button is released in stopship too, like:

function game:onEnterFrame()   if MoveLeft == true and MoveRight==false then Ship:setPosition(Ship:getX()-2,Ship:getY()) Ship:setRotation(-30) end if MoveRight == true and MoveLeft==false then Ship:setPosition(Ship:getX()+2,Ship:getY()) Ship:setRotation(30) end if MoveLeft == false and MoveRight == false then Ship:setRotation(0) end   if MoveLeft == true and MoveRight == true then Ship:setRotation(0) end   end   function game:MoveShip(event)   if Left:hitTestPoint(event.touch.x,event.touch.y) then MoveLeft = true end if Right:hitTestPoint(event.touch.x,event.touch.y) then MoveRight = true end if Fire:hitTestPoint(event.touch.x,event.touch.y) then print("fire") end end   end   function game:StopShip(event)   if Left:hitTestPoint(event.touch.x,event.touch.y) then MoveLeft = false end   if Right:hitTestPoint(event.touch.x,event.touch.y) then MoveRight = false end   end

keszegh

this solution will stop the ship if both buttons are pressed. if you want that the button pressed later should be the important one then just add a variable lastMove and set it to left/right in moveship and then in onenterframe if both MoveLeft and MoveRight are true then set your move according to lastMove.

antix

Here is a simple solution.. Just add another flag called "Moving". If it is true the rocket will move every frame. As an added bonus you only need one flag for the direction too.

function game:onEnterFrame() if Moving then if MoveLeft then Ship:setPosition(Ship:getX()-2,Ship:getY()) -- MOVE ROCKET LEFT Ship:setRotation(-30) else Ship:setPosition(Ship:getX()+2,Ship:getY()) -- MOVE ROCKET RIGHT Ship:setRotation(30) end end end   function game:MoveShip(event)   if Left:hitTestPoint(event.touch.x,event.touch.y) then Moving = true MoveLeft = true end   if Right:hitTestPoint(event.touch.x,event.touch.y) then Moving = true MoveLeft = false end   if Fire:hitTestPoint(event.touch.x,event.touch.y) then print("fire") end end   function game:StopShip(event) Moving = false end

If you don't want the rocket to ever stop moving left or right then you should comment out the Moving = false line in StopShip(event)