如何将小部件的可见性设置为false？

因此，我有这个函数：

local function addMainMenu()
    local widget = require( "widget" )

    -- 处理按钮事件的函数
    local function handleButtonEvent( event )

        if ( "ended" == event.phase ) then
            scene = "GAME"
        end
    end

    -- 创建小部件
    local button1 = widget.newButton(
        {
            label = "button",
            onEvent = handleButtonEvent,
            emboss = false,
            --圆角矩形按钮的属性
            shape = "roundedRect",
            width = 200,
            height = 40,
            cornerRadius = 2,
            fillColor = { default={0.9,0.9,0.9,1}, over={1,0.1,0.7,0.4} },
            strokeColor = { default={0,0,0,1}, over={0.8,0.8,1,1} },
            strokeWidth = 5
        }
    )

    -- 将按钮居中
    button1.x = display.contentCenterX
    button1.y = display.contentCenterY

    -- 更改按钮的标签文本
    button1:setLabel( "开始游戏" )
end

这将添加启动游戏的按钮，然后我有：

local function enterFrame()
    local dt = getDeltaTime()
    if (scene == "MAIN_MENU") then
         addMainMenu()
    elseif (scene == "GAME") then
        if (running == false) then
            startGame()
        else
            moveBg(dt)
            moveEnemy(enemy)
            updateScore()
        end
    elseif (scene == "GAME_OVER") then
        local gameOverLabel = display.newText( "Game Over!", 50, 20, native.systemFont, 16)
        gameOverLabel:setFillColor(1, 1, 1)
    end
end

如您所见，一旦我点击开始按钮，场景就会变为“GAME”，并且按钮应该消失。问题是：它还在那里。阅读文档后，我无法找到将其可见性设置为false的方法。如何停止显示小部件？