event.yDelta

概述

触摸事件起始坐标与其当前坐标之间在屏幕坐标系中的 y 轴距离。

示例

local object = display.newRect( display.contentCenterX, display.contentCenterY, 100, 100 )

local function move( event )
    if ( event.phase == "began" ) then
        display.getCurrentStage():setFocus( event.target )
        event.target.xStart = event.target.x
        event.target.yStart = event.target.y
    event.target.isFocus = true

    elseif ( event.phase == "moved" ) then
        if ( event.target.isFocus ) then
            event.target.x = event.target.xStart + event.xDelta
            event.target.y = event.target.yStart + event.yDelta
        end

    else
        display.getCurrentStage():setFocus( nil )
        event.target.isFocus = false

    end
end

object:addEventListener( "touch", move )