如何做 slide show

修改 內附的 slide show
把一個group 當一個元件來使用


module(..., package.seeall)

local screenW, screenH = display.contentWidth, display.contentHeight
local viewableScreenW, viewableScreenH = display.viewableContentWidth, display.viewableContentHeight
local screenOffsetW, screenOffsetH = display.contentWidth -  display.viewableContentWidth, display.contentHeight - display.viewableContentHeight

local imgNum = nil
local images = nil
local touchListener, nextImage, prevImage, cancelMove, initImage
local background
local imageNumberText, imageNumberTextShadow

function new( imageSet, slideBackground, top, bottom )
local pad = 20
local top = top or 0
local bottom = bottom or 0

local g = display.newGroup()

if slideBackground then
background = display.newImage(slideBackground, 0, 0, true)
else
background = display.newRect( 0, 0, screenW, screenH-(bottom-top) )

-- set anchors on the background
background.anchorX = 0
background.anchorY = 0

background:setFillColor(0, 0, 0)
end
g:insert(background)

images = {}
for i = 1,#imageSet do
local p = display.newImage(imageSet[i])
--local h = viewableScreenH-(top+bottom)
                local h = viewableScreenH-(bottom-top)
if p.width > viewableScreenW or p.height > h then
if p.width/viewableScreenW > p.height/h then
p.xScale = viewableScreenW/p.width
p.yScale = viewableScreenW/p.width
else
p.xScale = h/p.height
p.yScale = h/p.height
end
end
g:insert(p)
 
if (i > 1) then
p.x = screenW*1.5 + pad -- all images offscreen except the first one
else
p.x = screenW*.5
end

p.y = 0 --h*.5
                local h1 = p.xScale * p.height --算出對應的高
                p.y = h1 * .5

images[i] = p
end

local defaultString = "1 of " .. #images

local navBar = display.newGroup()
g:insert(navBar)

local navBarGraphic = display.newImage("navBar.png", 0, 0, false)
navBar:insert(navBarGraphic)
navBarGraphic.x = viewableScreenW*.5
navBarGraphic.y = 0

imageNumberText = display.newText(defaultString, 0, 0, native.systemFontBold, 14)
imageNumberText:setFillColor(1, 1, 1)
imageNumberTextShadow = display.newText(defaultString, 0, 0, native.systemFontBold, 14)
imageNumberTextShadow:setFillColor(0, 0, 0)
navBar:insert(imageNumberTextShadow)
navBar:insert(imageNumberText)
imageNumberText.x = navBar.width*.5
imageNumberText.y = navBarGraphic.y
imageNumberTextShadow.x = imageNumberText.x - 1
imageNumberTextShadow.y = imageNumberText.y - 1

navBar.y = math.floor(navBar.height*0.5)

imgNum = 1

--g.x = 0
--g.y = 0 --top + display.screenOriginY
     
                     
function touchListener (self, touch)
local phase = touch.phase
print("slides", phase)
if ( phase == "began" ) then
            -- Subsequent touch events will target button even if they are outside the contentBounds of button
            display.getCurrentStage():setFocus( self )
            self.isFocus = true

startPos = touch.x
prevPos = touch.x

--transition.to( navBar,  { time=200, alpha=math.abs(navBar.alpha-1) } )

        elseif( self.isFocus ) then
     
if ( phase == "moved" ) then

transition.to(navBar,  { time=400, alpha=0 } )

if tween then transition.cancel(tween) end

print(imgNum)

local delta = touch.x - prevPos
prevPos = touch.x

images[imgNum].x = images[imgNum].x + delta

if (images[imgNum-1]) then
images[imgNum-1].x = images[imgNum-1].x + delta
end

if (images[imgNum+1]) then
images[imgNum+1].x = images[imgNum+1].x + delta
end

elseif ( phase == "ended" or phase == "cancelled" ) then

dragDistance = touch.x - startPos
print("dragDistance: " .. dragDistance)

if (dragDistance < -40 and imgNum < #images) then
nextImage()
elseif (dragDistance > 40 and imgNum > 1) then
prevImage()
else
cancelMove()
end

if ( phase == "cancelled" ) then
cancelMove()
end

                                -- Allow touch events to be sent normally to the objects they "hit"
                                 display.getCurrentStage():setFocus( nil )
                                self.isFocus = false
transition.to(navBar,  { time=400, alpha=1 } )
end
end

return true

end

function setSlideNumber()
print("setSlideNumber", imgNum .. " of " .. #images)
imageNumberText.text = imgNum .. " of " .. #images
imageNumberTextShadow.text = imgNum .. " of " .. #images
             
end

function cancelTween()
if prevTween then
transition.cancel(prevTween)
end
prevTween = tween
end

function nextImage()
tween = transition.to( images[imgNum], {time=400, x=(screenW*.5 + pad)*-1, transition=easing.outExpo } )
tween = transition.to( images[imgNum+1], {time=400, x=screenW*.5, transition=easing.outExpo } )
imgNum = imgNum + 1
initImage(imgNum)
end

function prevImage()
tween = transition.to( images[imgNum], {time=400, x=screenW*1.5+pad, transition=easing.outExpo } )
tween = transition.to( images[imgNum-1], {time=400, x=screenW*.5, transition=easing.outExpo } )
imgNum = imgNum - 1
initImage(imgNum)
end

function cancelMove()
tween = transition.to( images[imgNum], {time=400, x=screenW*.5, transition=easing.outExpo } )
tween = transition.to( images[imgNum-1], {time=400, x=(screenW*.5 + pad)*-1, transition=easing.outExpo } )
tween = transition.to( images[imgNum+1], {time=400, x=screenW*1.5+pad, transition=easing.outExpo } )
end

function initImage(num)
if (num < #images) then
images[num+1].x = screenW*1.5 + pad
end
if (num > 1) then
images[num-1].x = (screenW*.5 + pad)*-1
end
setSlideNumber()
end

background.touch = touchListener
background:addEventListener( "touch", background )

------------------------
-- Define public methods

function g:jumpToImage(num)
local i
print("jumpToImage")
print("#images", #images)
for i = 1, #images do
if i < num then
images[i].x = -screenW*.5;
elseif i > num then
images[i].x = screenW*1.5 + pad
else
images[i].x = screenW*.5 - pad
end
end
imgNum = num
initImage(imgNum)
end

function g:cleanUp()
print("slides cleanUp")
background:removeEventListener("touch", touchListener)
end

return g
end


呼叫方法

local myImages = {
"myPhotos1.jpg",
"myPhotos2.jpg",
"myPhotos3.jpg",
"myPhotos4.jpg"
}

local sv = slideView.new( myImages ,nil,1,100)

後面的坐標可以不用傳