如何在 Corona 和 Lua 中使用“id = tostring(i)”

我最近看到了像这样的东西

if(ebasRating_Arr[i] == 0) then
        radioButton_0 = widget.newSwitch {
            left = 565,
            style = "radio",
            initialSwitchState = true,
            id = tostring(i),
            width = 60,
            height = 60,
            onPress = setEBASRating0
        }
        radioGroup:insert( radioButton_0 )

        radioButton_1 = widget.newSwitch {
            style = "radio",
            id = tostring(i),
            initialSwitchState = false,
            width = 60,
            height = 60,
            onPress = setEBASRating1
        }
        radioGroup:insert( radioButton_1 )

注意第6行和第13行的“id = tostring(i)”。所以我正在尝试使用 id = tostring(i) ，想查找它的含义。有人能告诉我它真正的含义吗？那么我问题的第二部分是我怎样能在我的代码中使用像id = tostring(i)这样的东西

 local madrs = display.newGroup()
local function textListener( event )

if ( event.phase == "began" ) then

elseif ( event.phase == "ended" or event.phase == "submitted" ) then
    -- 输出“defaultField”中的结果文本

print( event.target.text )

elseif ( event.phase == "editing" ) then
    print( event.newCharacters )
    print( event.oldText )
    print( event.startPosition )
    print( event.text )
    end
end