I’m trying to constrain the drag movement between the screen boundaries but If you move fast enough it goes past the 50 and 200 limits
If you move fast enough it goes past the 50 and 200 limits local r = display.newRect(100,100,30,30) r:addEventListener("touch",function(event) if event.phase == "began" then display.getCurrentStage():setFocus(event.target) event.target.ox = event.target.x end if event.phase == "moved" and ((event.xStart \< event.x and event.target.x \< 200) or (event.xStart \> event.x and event.target.x \> 50)) then event.target.x = event.x - event.xStart + event.target.ox + 1 end if event.phase == "ended" or event.phase == "cancelled" then display.getCurrentStage():setFocus(nil) end end)
Anyone had this problem before? Is there a solution for this problem?
I would personally check the x, y at the end of the touch handler on the actual object and if it was out of bounds, move it back. You will need to save the event.target.x and .y at the top before you start the IF and then at the bottom check to see if you’re out of bounds and if so, set the x, y back to what you saved at the top.
I actually just added this in a sample app i am doing to show Corona at a meetup.
Do the following
[lua]
xMin = 40; xMax = 280;
local function onTouch( event )
local t = event.target
local phase = event.phase
if “began” == phase then
– Make target the top-most object
local parent = t.parent
parent:insert( t )
display.getCurrentStage():setFocus( t, event.id )
t.isFocus = true
– Store initial touch position on the actual object - prevents jumping when touched
t.xStart = event.x - t.x
t.yStart = event.y - t.y
elseif t.isFocus then
if “moved” == phase then
print(t.xStart)
t.x = event.x - t.xStart
if (t.x < xMin) then t.x = xMin end
if (t.x > xMax) then t.x = xMax end
--t.y = event.y - t.yStart
elseif “ended” == phase or “cancelled” == phase then
display.getCurrentStage():setFocus( t, nil )
t.isFocus = false
end
end
--This tells the system that the event
– should not be propagated to listeners of any objects underneath.
return true
end
I would personally check the x, y at the end of the touch handler on the actual object and if it was out of bounds, move it back. You will need to save the event.target.x and .y at the top before you start the IF and then at the bottom check to see if you’re out of bounds and if so, set the x, y back to what you saved at the top.
I actually just added this in a sample app i am doing to show Corona at a meetup.
Do the following
[lua]
xMin = 40; xMax = 280;
local function onTouch( event )
local t = event.target
local phase = event.phase
if “began” == phase then
– Make target the top-most object
local parent = t.parent
parent:insert( t )
display.getCurrentStage():setFocus( t, event.id )
t.isFocus = true
– Store initial touch position on the actual object - prevents jumping when touched
t.xStart = event.x - t.x
t.yStart = event.y - t.y
elseif t.isFocus then
if “moved” == phase then
print(t.xStart)
t.x = event.x - t.xStart
if (t.x < xMin) then t.x = xMin end
if (t.x > xMax) then t.x = xMax end
--t.y = event.y - t.yStart
elseif “ended” == phase or “cancelled” == phase then
display.getCurrentStage():setFocus( t, nil )
t.isFocus = false
end
end
--This tells the system that the event
– should not be propagated to listeners of any objects underneath.
return true
end
