对 combotree 的改进, 包括展开到当前节点, 键盘操作树, 检索过滤

转载 http://www.jeasyui.com/forum/index.php?PHPSESSID=vr7i9f3dv7eg3868rb4gvbqg90&topic=3217.0
function onCombotreeShowPanel(){

      // 显示下拉框, 展开到当前节点

      var t = $(this).combotree('tree');

      var node = t.tree('getSelected');

      if (node){

         t.tree('expandTo', node.target);

         }

   }

   

(function($){

   // 实现下拉树的本地检索功能

   $.fn.combotree.defaults.editable = true;

   

   $.extend($.fn.combotree.methods,{

      nav:function(jq, dir){

         return jq.each(function(){

            var opts = $(this).combotree('options');

            var t = $(this).combotree('tree');

            var nodes = t.tree('getChildren');

            if (!nodes.length) {return;}

            

            var node = t.tree('getSelected');

            if (!node){

               t.tree('select', dir>0 ? nodes[0].target : nodes[nodes.length-1].target);

            } else {

               var index = 0;

               for(var i=0; i<nodes.length; i++){

                  if (nodes.target == node.target){

                     index = i;

                     break;

                  }

               }

               

               if (dir>0){

                  while (index < nodes.length-1){

                     index++;

                     if ($(nodes[index].target).is(':visible')){break;}

                  }

               } else {

                  while (index > 0){

                     index--;

                     if ($(nodes[index].target).is(':visible')){break;}

                  }

               }

               t.tree('select',nodes[index].target);

               t.tree('scrollTo',nodes[index].target);

               

            }

            if (opts.selectOnNavigation){

               var node = t.tree('getSelected');

               $(this).combotree("setValue", node.id);

//               $(node.target).trigger('click');

//               $(this).combotree('showPanel');

            }

         });

      }

   });

   

   // 检测当前能否编辑

   function checkEditable(el){

      var opt = el.combo("options");                  

      if (opt.readonly || opt.disabled) {

         return false;

      }

      return opt.editable;

   }

   

   $.extend($.fn.combotree.defaults.keyHandler,{

      up:function(){

         var el = $(this);

         if (!checkEditable(el)) return;

         

         // 当前 panel 已展开, 则处理nav, 否则先显示 panel

         var p = el.combotree('panel');

         if (p.is(':visible')){

            el.combotree('nav', -1);

         }else{

            el.combotree('showPanel');   

         }

      },

      down:function(){

         var el = $(this);

         if (!checkEditable(el)) return;

         

         // 当前 panel 已展开, 则处理nav, 否则先显示 panel

         var p = el.combotree('panel');

         if (p.is(':visible')){

            el.combotree('nav', 1);

         }else{

            el.combotree('showPanel');   

         }

      },

      right:function(){

         var el = $(this);

         if (!checkEditable(el)) return;

         

         var p = el.combotree('panel');

         if (!p.is(':visible')){return;}

         

         // 展开当前节点的分支

         var t = el.combotree('tree');

         var node = t.tree('getSelected');

         if (node){

            t.tree('expand', node.target);

         }

      },

      left:function(){

         var el = $(this);

         if (!checkEditable(el)) return;

         

         var p = el.combotree('panel');

         if (!p.is(':visible')){return;}

         

         var t = el.combotree('tree');

         var node = t.tree('getSelected');

         if (node){

            var isLeaf = t.tree('isLeaf', node.target);

            if (!isLeaf && node.state == "open"){

               // 如果不是叶子节点, 并且当前是展开状态, 则收缩当前分支

               t.tree('collapse', node.target);

            }else{

               // 如果有父节点, 则收缩父节点, 并且选中父节点

               var parent = t.tree('getParent', node.target);

               if (parent){

                  t.tree('collapse', parent.target);

                  t.tree('select', parent.target);

                  

                  // 需要时, 更新textbox的值

                  var opts = el.combo("options");   

                  if (opts.selectOnNavigation){

                     el.combotree("setValue", parent.id);                        

                  }

               }

            }

         }

      },

      enter:function(){

         var el = $(this);

         if (!checkEditable(el)) return;

         

         var p = el.combotree('panel');

         if (!p.is(':visible')){return;}

         

         var t = el.combotree('tree');

         var node = t.tree('getSelected');

         if (node){

            $(node.target).trigger('click');

         }

         $(this).combotree('hidePanel');

      }

   });

   

   $.extend($.fn.combotree.defaults.keyHandler,{

      query:function(q){

         if (q == "") {

            // 用于触发 onchange

            $(this).combotree('setValue', "");

            return;

         }

         

         var opts = $(this).combotree('options');

         

         var t = $(this).combotree('tree');

         var nodes = t.tree('getChildren');

         for(var i=0; i<nodes.length; i++){

            var node = nodes;

            

//            if (node.text.indexOf(q) >= 0){

            if (opts.filter &
4000
amp;& opts.filter(q, node)){

               if (q != ""){

                  // 必须展开, 否则显示不出来

                  t.tree('expandTo', node.target);

               }

               $(node.target).show();

            } else {

               $(node.target).hide();

            }

         }

         

         // 点击下拉, 则恢复显示

         if (!opts.hasSetEvents){

            opts.hasSetEvents = true;

            var onShowPanel = opts.onShowPanel;

            opts.onShowPanel = function(){

               // 恢复显示

               var nodes = t.tree('getChildren');

               for(var i=0; i<nodes.length; i++){

                  $(nodes.target).show();

               }

               onShowPanel.call(this);

            };

            

            $(this).combo('options').onShowPanel = opts.onShowPanel;

         }

      }

   });

})(jQuery);