移动端touch滑动事件监听
<!doctype html> <html> <head> <meta charset="utf-8"> <title>javascript判断手指在移动端上滑动的方向</title> <script src="http://libs.baidu.com/jquery/1.11.3/jquery.min.js"></script> <style> </style> </head> <body> 请在移动端,PC上无法查看效果,滑动查看效果<script> var startx, starty; //获得角度 function getAngle(angx, angy) { return Math.atan2(angy, angx) * 180 / Math.PI; }; //根据起点终点返回方向 1向上 2向下 3向左 4向右 0未滑动 function getDirection(startx, starty, endx, endy) { var angx = endx - startx; var angy = endy - starty; var result = 0; //如果滑动距离太短 if (Math.abs(angx) < 2 && Math.abs(angy) < 2) { return result; } var angle = getAngle(angx, angy); if (angle >= -135 && angle <= -45) { result = 1; } else if (angle > 45 && angle < 135) { result = 2; } else if ((angle >= 135 && angle <= 180) || (angle >= -180 && angle < -135)) { result = 3; } else if (angle >= -45 && angle <= 45) { result = 4; } return result; } //手指接触屏幕 document.addEventListener("touchstart", function(e){ startx = e.touches[0].pageX; starty = e.touches[0].pageY; }, false); //手指离开屏幕 document.addEventListener("touchend", function(e) { var endx, endy; endx = e.changedTouches[0].pageX; endy = e.changedTouches[0].pageY; var direction = getDirection(startx, starty, endx, endy); switch (direction) { case 0: alert("未滑动!"); break; case 1: alert("向上!"); break; case 2: alert("向下!"); break; case 3: alert("向左!"); break; case 4: alert("向右!"); break; default: } }, false); </script> </body> </html>
文章出自:https://blog.csdn.net/qq_39198420/article/details/76502267;
———————————— 方向错了,停下来就是进步 ————————————