jQuery实现拖拽效果插件的方法教程

本文实例讲述了jquery实现拖拽效果插件的方法。分享给大家供大家参考。具体如下：

下面的jquery插件允许你通过鼠标右键点击拖动overflow的元素，这个插件可以在移动设备上运行

/**
* jquery drag and scroll
*
* copyright (c) 2012 ryan naddy (ryannaddy.com)
* dual licensed under the mit and gpl licenses:
* https://www.opensource.org/licenses/mit-license.php
* https://www.gnu.org/licenses/gpl.html
*/
(function($){
  var down = false;
  var prevx = 0;
  var prevy = 0;
  var x = 0;
  var y = 0;
  var px = 0;
  var py = 0;
  var lastpx = -1;
  var lastpy = -1;
  var $target = null;
  var $me = null;
  var $selector = "";
  var settings = {
    mousebutton: 3,
    context: false,
    selecttext: false
  };
  $.fn.dragscroll = function(options){
    settings = $.extend(settings, options);
    $selector = $(this).selector;
    $(this).contextmenu(function(){
      return false;
    }).bind("mousedown touchstart", function(e){
      $me = $(this);
      e = event.touches ? event.touches[0] : e;
      $target = $(e.target);
      $target = $target.closest($selector);
      if(settings.viewport){
        if(!settings.context){
          $me.contextmenu(function(){
            return false;
          });
        }
      }
      if(!settings.selecttext){
        $me.attr('unselectable', 'on').css('user-select', 'none').on('selectstart', false);
      }
      $me = $me.closest($selector);
      if($target && $me.attr("id") != $target.attr("id")){
        return false;
      }
      if(e.which == settings.mousebutton || event.touches){
        $me.css("cursor", "move");
        down = true;
      }
      px = $me.scrollleft();
      py = $me.scrolltop();
      x = px + e.pagex;
      y = py + e.pagey;
      prevx = x;
      prevy = y;
      return true;
    }).bind("mouseup touchend", function(e){
      $me = $(this);
      e = event.touches ? event.touches[0] : e;
      $me.css("cursor", "auto");
      down = false;
    }).bind("mousemove touchmove", function(e){
      $me = $(this);
      $me = $me.closest($selector);
      e = event.touches ? event.touches[0] : e;
      if((e.which == settings.mousebutton || event.touches) && down){
        if(event.touches){
          event.preventdefault();
        }
        if($target && $me.attr("id") != $target.attr("id")){
          return false;
        }
        $me.css("cursor", "move");
        px = $me.scrollleft();
        py = $me.scrolltop();
        x = px + e.pagex;
        y = py + e.pagey;
        $me.scrollleft(px + (-(x - prevx)));
        $me.scrolltop(py + (-(y - prevy)));
        prevx = x - (x - prevx);
        prevy = y - (y - prevy);
        if(lastpx == px)
          prevx = x;
        if(lastpy == py)
          prevy = y;
        lastpx = px;
        lastpy = py;
      }
      return true;
    });
    return this;
  }
})(jquery);

希望本文所述对大家的jquery程序设计有所帮助。