通过调用update来更新位置达到的移动效果，和背景滚动有点类似，一旦滚动结束就重置为起点，开始新的滚动。只是为了达到在某个区域内滚动而不至于超出这个区域，有时候会用一些前景图来做遮盖，所以这个时候其实字幕或者公告是有在后面滚动的，但是被遮住了，因此看起来就像是只在某个区域内滚动。

 

RollingFont=class("RollingFont",function()

    return cc.Layer:create()

end)

RollingFont.ctor=function(self)

    local cache=cc.SpriteFrameCache:getInstance()

    cache:addSpriteFrames("rollfont/ui_serverlist.plist")

    self.size=cc.Director:getInstance():getWinSize()

    --注册定时事件

    self:registerScriptHandler(function(tag)

        local scheduler=nil

        if tag=="enter" then

            scheduler=self:onEnter()

        elseif tag=="exit" then

            self:onExit(scheduler)

        end

    end)

end

RollingFont.createText=function(self,text)

    local ttfConfig = {}

    ttfConfig.fontFilePath="fonts/arial.ttf"

    ttfConfig.fontSize=11.4

    local label = cc.Label:createWithTTF(ttfConfig, text, cc.TEXT_ALIGNMENT_LEFT, self.size.width)

    label:setTextColor( cc.c4b(, , , ) )

    return label

end

--垂直滚动字幕

RollingFont.verticalFont=function(self)

    --添加垂直滚动字幕边框

    local listbox=cc.Sprite:createWithSpriteFrameName("login_listbase.png")

    listbox:setPosition(cc.p(self.size.width/,self.size.height/+))

    listbox:setScale(1.2)

    self:addChild(listbox)

    local listboxSize=listbox:getBoundingBox()

    local listboxX=listbox:getPositionX()

    local listboxY=listbox:getPositionY()

    self.verticalRect=cc.rect(listboxX-listboxSize.width/,listboxY-listboxSize.height/,listboxSize.width,listboxSize.height)

    --垂直滚动字幕

    local text="1.Hi! Welcome to My Blog,This is a Sample about\nfont vertical move with Cocos2dx 3.x Lua\n"

    local label=self:createText(text)

    label:setPosition(self.verticalRect.x+self.verticalRect.width-,self.verticalRect.y)

    label:setAnchorPoint(,)

    self:addChild(label)

    self.labelVertical=label

    --字幕遮罩

    local fg=cc.Sprite:create("rollfont/fg.png")

    fg:setPosition(cc.p(self.verticalRect.x+self.verticalRect.width/,self.verticalRect.y+self.verticalRect.height/));

    self:addChild(fg);

end

--水平滚动字幕

RollingFont.horizontalFont=function(self)

    --添加水平滚动字幕边框

    local listbox=cc.Sprite:createWithSpriteFrameName("login_textbase.png")

    listbox:setPosition(cc.p(self.size.width/,self.size.height/-))

    listbox:setScaleX(2.5)

    self:addChild(listbox)

    local listboxSize=listbox:getBoundingBox()

    local listboxX=listbox:getPositionX()

    local listboxY=listbox:getPositionY()

    --水平滚动字幕

    local text="1.Hi! This is a Sample about font vertical move with Cocos2dx 3.x Lua"

    local label=self:createText(text)

    label:setPosition(self.size.width,self.verticalRect.y-)

    label:setAnchorPoint(,)

    self:addChild(label)

    self.labelHorizontal=label

    local labelSize=label:getBoundingBox()

    self.horizontalSize=cc.rect(,,labelSize.width,labelSize.height)

end

RollingFont.onEnter=function(self)

    --垂直滚动最大和最小高度

    local hlabelSize=self.labelVertical:getBoundingBox()

    local hmaxHeight=self.verticalRect.y+self.verticalRect.height+hlabelSize.height

    local hminHeight=self.verticalRect.y+

    --水平滚动最大宽度和最小宽度

    local vmaxWidth=self.size.width

    local vminWidth=-self.horizontalSize.width

    local function schedule()

        --垂直滚动

        local y=self.labelVertical:getPositionY()

        y=y+

        if y >= hmaxHeight then

            y=hminHeight

        end

        self.labelVertical:setPositionY(y)

        --水平滚动

        local x=self.labelHorizontal:getPositionX()

        x=x-

        if x <= vminWidth then

            x=vmaxWidth

        end

        self.labelHorizontal:setPositionX(x)

    end

    local scheduler=cc.Director:getInstance():getScheduler()

    scheduler:scheduleScriptFunc(schedule,0.02,false)

    return scheduler

end

RollingFont.onExit=function(self,scheduler)

    if scheduler then

        cc.Director:getInstance():getScheduler():unscheduleScriptEntry(scheduler)

    end

end

RollingFont.create=function(self)

    local roll=RollingFont.new()

    roll:verticalFont()

    roll:horizontalFont()

    return roll

end

return RollingFont