touch event

Getting Started Newbie Questions
#1

local physics=require(“physics”);

physics.start();

physics.setGravity(0,0);

local ball=display.newImageRect(“c.png”,200,100);

ball.x=300;

ball.y=200;

physics.addBody(ball);

local function activateball(self,event)

 self:applyForce(0,-1.5,self.x,self.y)

  end

local function tc(event)

   if event.phase=="began"then 

     ball.enterFrame=activateball

    Runtime:addEventListener(“enterFrame”,ball)

   end

    if event.phase=="ended"then

    Runtime:removeEventListener(“enterFrame”,ball);

  end

end

Runtime:addEventListener(“touch”,tc);

hii…i   wrote this program to learn touch event .Everything is good but there is a problem in last phase of touch(ended phase).when i just tap out ,my object  BALL doesnt stop at that point where i just tapped out .

and i also want to share that  i have learnt this method from tutorial        https://www.youtube.com/watch?v=_7kCULfpDWY      

#2

Formatting your code to help future readers:

local physics=require("physics"); physics.start(); physics.setGravity(0,0); local ball=display.newImageRect("c.png",200,100); ball.x=300; ball.y=200; physics.addBody(ball); local function activateball(self,event) self:applyForce(0,-1.5,self.x,self.y) end local function tc(event) if event.phase=="began"then ball.enterFrame=activateball Runtime:addEventListener("enterFrame",ball) end if event.phase=="ended"then Runtime:removeEventListener("enterFrame",ball); end end Runtime:addEventListener("touch",tc);

One thing I can see right away is you need to set and release focus to make this work consistently.

https://docs.coronalabs.com/daily/api/type/StageObject/setFocus.html

This is better…

local function tc(event) local phase = event.phase local id = event.id local target = event.target if( phase == "began" ) then display.currentStage:setFocus( target, id ) target.isFocus = true target.enterFrame = activateball Runtime:addEventListener("enterFrame",target) elseif( target.isFocus ) then if( phase == "ended" ) then display.currentStage:setFocus( target, nil ) target.isFocus = false Runtime:removeEventListener("enterFrame",target) end end end
#3

i have tried the way you suggested  but the problem remain same.whenever my touch event ended .my object doesnt  stop moving.

here is my code

local physics=require(“physics”)

physics.start();

physics.setGravity(0,0);

local wall=display.newImageRect(“c.png”,200,100);

wall.x=200;

wall.y=250;

physics.addBody(wall);

wall.myName=“wall”;

local function active(self,event)

  self:applyForce(0,-1.5,self.x,self.y);

end

local function  touchscreen( event )

  local wall=event.target;

  local id = event.id

  local phase=event.phase;

  if (“began”==phase)then 

    --set touch focus on the wall

    display.currentStage:setFocus(wall,id);

  wall.isFocus = true

      wall.enterFrame = active

      Runtime:addEventListener(“enterFrame”,wall)

  

 elseif( wall.isFocus ) then

      if( phase == “ended” ) then 

         display.currentStage:setFocus( wall, nil )

         wall.isFocus = false

         Runtime:removeEventListener(“enterFrame”,wall)

     end

   end

  return true;

end

wall:addEventListener(“touch”,touchscreen);

#4

If I should make a guess… 2 things…

Your gravity is 0    -so no counter force to make the ball stop.

or

I don’t see anything telling the ball to stop in the code as a whole… 

In the top you send the ball moving: self:applyForce(0,-1.5, selfx,selfy)

Down at the:  if(phase == “ended”)  I think you are missing something to set the force to  zero again.

#5

ah…let me try but if i had to make a resistance force than what is the purpose of command

 Runtime:removeEventListener(“enterFrame”,wall) 

#6

i have tried everything but i dont know what to do to stop my object and how the command

 Runtime:removeEventListener(“enterFrame”,wall)      is working

#7

Please use code formatting.  Click the blue <> button in the row with Bold, Italic, etc. Paste your code into the popup window. It will make your code easier for community members to read and understand.

Thanks

Rob

#8 
local physics=require("physics") physics.start(); physics.setGravity(0,0); local wall=display.newImageRect("c.png",200,100); wall.x=200; wall.y=250; physics.addBody(wall,"dynamic",{density=.1,friction=.2}); wall.myName="wall"; local function active(self,event) self:applyForce(0,-1.5,self.x,self.y); end local function touchscreen( event ) local phase=event.phase; if ("began"==phase)then wall.enterFrame = active Runtime:addEventListener("enterFrame",wall) end if( phase == "ended" ) then wall:removeEventListener("enterFrame",wall) end return true; end Runtime:addEventListener("touch",touchscreen);

my problem is, whenever my touch event is  ended…my object doesnt stop…

#9

  1. Thanks for putting the code in a code block but remember you also have to take the time to make it legible.  If that means posting, re-editing, re-posting.  Please do it.  
     
    You’re asking us to spend our time to solve a problem you are stuck on, so you have to make it as easy as possible for us to help you.
     
     
     

  2. This is how I would correct the issue you are encountering, or at least as I understand it.
     
    You want the ‘wall’ to move when touching the screen and to stop when you are not touching the screen.  I am also guessing you don’t want it to rotate.
     
    (Notice the clean and tight formatting of this post)

    local physics=require(“physics”) physics.start() physics.setGravity( 0, 0 ) local wall = display.newImageRect( “c.png”, 200, 100 ) wall.x = 200 wall.y = 250 wall.myName = “wall” wall.isMoving = false physics.addBody( wall, “dynamic”, { density = 0.1, friction = 0.2 } ) wall.isFixedRotation = true – This is a table listener – I find them superior because (among other reasons) they are easy to clean later function wall.enterFrame( self ) if( self.isMoving == false ) then return end self:applyForce( 0, -1.5, self.x, self.y ) end – This is another table listener function wall.touch( self, event ) local phase = event.phase if( “began” == phase ) then self.isMoving = true elseif( phase == “ended” ) then self.isMoving = false self:setLinearVelocity( 0, 0 ) end return true end – This function will clean up (remove) the – Runtime table-listeners when you delete the wall function wall.finalize( self ) Runtime:removeEventListener( “enterScreen”, self ) Runtime:removeventListener( “touch”, self ) end – Start listening wall:addEventListener( “finalize” ) Runtime:addEventListener( “enterFrame”, wall ) Runtime:addEventListener( “touch”, wall )

#10

You have expressed confusion about Runtime:* listeners.

This should help you start to understand listeners in general:

https://docs.coronalabs.com/daily/guide/events/detectEvents/index.html

#11

@kumarchetan312,

If you’re still reading this and feel the answer I gave helped you out, can you give me five minutes or less?

Please see this post and submit an idea or two:

https://forums.coronalabs.com/topic/66772-ssk2-lets-make-1-brainstorming/

#12

well i have changed my code and rewrote it,but this time my wall doesnt move at all…it just look like my touch event is not working  and yeah i would love to submit some ideas .

#13

I typoed… replace word ‘enterScreen’ with  ‘enterFrame’.

Note: This was was all only tested in my mind…

#14

Here is a working example: http://github.com/roaminggamer/RG_FreeStuff/raw/master/AskEd/2016/12/moving_wall.zip

https://www.youtube.com/watch?v=K6qofD1f570&feature=youtu.be

#15

thanks a lot

#16

Formatting your code to help future readers:

local physics=require("physics"); physics.start(); physics.setGravity(0,0); local ball=display.newImageRect("c.png",200,100); ball.x=300; ball.y=200; physics.addBody(ball); local function activateball(self,event) self:applyForce(0,-1.5,self.x,self.y) end local function tc(event) if event.phase=="began"then ball.enterFrame=activateball Runtime:addEventListener("enterFrame",ball) end if event.phase=="ended"then Runtime:removeEventListener("enterFrame",ball); end end Runtime:addEventListener("touch",tc);

One thing I can see right away is you need to set and release focus to make this work consistently.

https://docs.coronalabs.com/daily/api/type/StageObject/setFocus.html

This is better…

local function tc(event) local phase = event.phase local id = event.id local target = event.target if( phase == "began" ) then display.currentStage:setFocus( target, id ) target.isFocus = true target.enterFrame = activateball Runtime:addEventListener("enterFrame",target) elseif( target.isFocus ) then if( phase == "ended" ) then display.currentStage:setFocus( target, nil ) target.isFocus = false Runtime:removeEventListener("enterFrame",target) end end end
#17

i have tried the way you suggested  but the problem remain same.whenever my touch event ended .my object doesnt  stop moving.

here is my code

local physics=require(“physics”)

physics.start();

physics.setGravity(0,0);

local wall=display.newImageRect(“c.png”,200,100);

wall.x=200;

wall.y=250;

physics.addBody(wall);

wall.myName=“wall”;

local function active(self,event)

  self:applyForce(0,-1.5,self.x,self.y);

end

local function  touchscreen( event )

  local wall=event.target;

  local id = event.id

  local phase=event.phase;

  if (“began”==phase)then 

    --set touch focus on the wall

    display.currentStage:setFocus(wall,id);

  wall.isFocus = true

      wall.enterFrame = active

      Runtime:addEventListener(“enterFrame”,wall)

  

 elseif( wall.isFocus ) then

      if( phase == “ended” ) then 

         display.currentStage:setFocus( wall, nil )

         wall.isFocus = false

         Runtime:removeEventListener(“enterFrame”,wall)

     end

   end

  return true;

end

wall:addEventListener(“touch”,touchscreen);

#18

If I should make a guess… 2 things…

Your gravity is 0    -so no counter force to make the ball stop.

or

I don’t see anything telling the ball to stop in the code as a whole… 

In the top you send the ball moving: self:applyForce(0,-1.5, selfx,selfy)

Down at the:  if(phase == “ended”)  I think you are missing something to set the force to  zero again.

#19

ah…let me try but if i had to make a resistance force than what is the purpose of command

 Runtime:removeEventListener(“enterFrame”,wall) 

#20

i have tried everything but i dont know what to do to stop my object and how the command

 Runtime:removeEventListener(“enterFrame”,wall)      is working