Ext2.0 check box 树扩展

EXT2.0 checkbox树的扩展(支持单选,级联多选,只选叶子等)
在ext1.x里,树是没有checkbox的, 幸好在2.X版本里提供了这个功能, 在许多应用里, 带有checkbox的树使用还是很常见的



Ext2.X提供了简单的checkbox实现,但对于一些复杂的需求,如: 级联多选(选中父结点,自选中其所有子结点和所有父结点) , 单选等等, Ext2.X并没有帮我们实现



还有最难解决的情况, 当树是异步的时候, 要想级联多选, 实现起来有些难度



在此, 通过对Ext.tree.TreeNodeUI进行扩展,这些问题都得到很好的解决



Js代码
/**  
* @class Ext.tree.TreeCheckNodeUI  
* @extends Ext.tree.TreeNodeUI  
*   
* 对 Ext.tree.TreeNodeUI 进行checkbox功能的扩展,后台返回的结点信息不用非要包含checked属性  
*   
* 扩展的功能点有：  
* 一、支持只对树的叶子进行选择  
*    只有当返回的树结点属性leaf = true 时，结点才有checkbox可选  
*    使用时，只需在声明树时，加上属性 onlyLeafCheckable: true 既可，默认是false  
*   
* 二、支持对树的单选  
*    只允许选择一个结点  
*    使用时，只需在声明树时，加上属性 checkModel: "single" 既可  
*   
* 二、支持对树的级联多选   
*    当选择结点时，自动选择该结点下的所有子结点，以及该结点的所有父结点（根结点除外），特别是支持异步，当子结点还没显示时，会从后台取得子结点，然后将其选中/取消选中  
*    使用时，只需在声明树时，加上属性 checkModel: "cascade" 既可  
*   
* 三、添加"check"事件  
*    该事件会在树结点的checkbox发生改变时触发  
*    使用时，只需给树注册事件,如：  
*    tree.on("check",function(node,checked){...});  
*   
* 默认情况下，checkModel为'multiple'，也就是多选，onlyLeafCheckable为false，所有结点都可选  
*   
* 使用方法：在loader里加上 baseAttrs:{uiProvider:Ext.tree.TreeCheckNodeUI} 既可.  
* 例如：  
*   var tree = new Ext.tree.TreePanel({  
*      el:'tree-ct',  
*      width:568,  
*      height:300,  
*      checkModel: 'cascade',   //对树的级联多选  
*      onlyLeafCheckable: false,//对树所有结点都可选  
*      animate: false,  
*      rootVisible: false,  
*      autoScroll:true,  
*      loader: new Ext.tree.DWRTreeLoader({  
*          dwrCall:Tmplt.getTmpltTree,  
*          baseAttrs: { uiProvider: Ext.tree.TreeCheckNodeUI } //添加 uiProvider 属性  
*      }),  
*      root: new Ext.tree.AsyncTreeNode({ id:'0' })  
*  });  
*  tree.on("check",function(node,checked){alert(node.text+" = "+checked)}); //注册"check"事件  
*  tree.render();  
*   
*/  
  
Ext.tree.TreeCheckNodeUI = function() {   
    //'multiple':多选; 'single':单选; 'cascade':级联多选   
    this.checkModel = 'multiple';   
       
    //only leaf can checked   
    this.onlyLeafCheckable = false;   
       
    Ext.tree.TreeCheckNodeUI.superclass.constructor.apply(this, arguments);   
};   
  
Ext.extend(Ext.tree.TreeCheckNodeUI, Ext.tree.TreeNodeUI, {   
  
    renderElements : function(n, a, targetNode, bulkRender){   
        var tree = n.getOwnerTree();   
        this.checkModel = tree.checkModel || this.checkModel;   
        this.onlyLeafCheckable = tree.onlyLeafCheckable || false;   
           
        // add some indent caching, this helps performance when rendering a large tree   
        this.indentMarkup = n.parentNode ? n.parentNode.ui.getChildIndent() : '';   
  
    var cb = (!this.onlyLeafCheckable || a.leaf);   
        var href = a.href ? a.href : Ext.isGecko ? "" : "#";   
        var buf = ['<li class="x-tree-node"><div ext:tree-node-id="',n.id,'" class="x-tree-node-el x-tree-node-leaf x-unselectable ', a.cls,'" unselectable="on">',   
            '<span class="x-tree-node-indent">',this.indentMarkup,"</span>",   
            '<img src="', this.emptyIcon, '" class="x-tree-ec-icon x-tree-elbow" />',   
            '<img src="', a.icon || this.emptyIcon, '" class="x-tree-node-icon',(a.icon ? " x-tree-node-inline-icon" : ""),(a.iconCls ? " "+a.iconCls : ""),'" unselectable="on" />',   
            cb ? ('<input class="x-tree-node-cb" type="checkbox" ' + (a.checked ? 'checked="checked" />' : '/>')) : '',   
            '<a hidefocus="on" class="x-tree-node-anchor" href="',href,'" tabIndex="1" ',   
             a.hrefTarget ? ' target="'+a.hrefTarget+'"' : "", '><span unselectable="on">',n.text,"</span></a></div>",   
            '<ul class="x-tree-node-ct" style="display:none;"></ul>',   
            "</li>"].join('');   
  
        var nel;   
        if(bulkRender !== true && n.nextSibling && (nel = n.nextSibling.ui.getEl())){   
            this.wrap = Ext.DomHelper.insertHtml("beforeBegin", nel, buf);   
        }else{   
            this.wrap = Ext.DomHelper.insertHtml("beforeEnd", targetNode, buf);   
        }   
           
        this.elNode = this.wrap.childNodes[0];   
        this.ctNode = this.wrap.childNodes[1];   
        var cs = this.elNode.childNodes;   
        this.indentNode = cs[0];   
        this.ecNode = cs[1];   
        this.iconNode = cs[2];   
        var index = 3;   
        if(cb){   
            this.checkbox = cs[3];   
            Ext.fly(this.checkbox).on('click', this.check.createDelegate(this,[null]));   
            index++;   
        }   
        this.anchor = cs[index];   
        this.textNode = cs[index].firstChild;   
    },   
       
    // private   
    check : function(checked){   
        var n = this.node;   
        var tree = n.getOwnerTree();   
        this.checkModel = tree.checkModel || this.checkModel;   
           
        if( checked === null ) {   
            checked = this.checkbox.checked;   
        } else {   
            this.checkbox.checked = checked;   
        }   
           
        n.attributes.checked = checked;   
        tree.fireEvent('check', n, checked);   
           
        if(!this.onlyLeafCheckable && this.checkModel == 'cascade'){   
            var parentNode = n.parentNode;   
            if(parentNode !== null) {   
                this.parentCheck(parentNode,checked);   
            }   
            if( !n.expanded && !n.childrenRendered ) {   
                n.expand(false,false,this.childCheck);   
            }   
            else {   
                this.childCheck(n);   
            }   
        }else if(this.checkModel == 'single'){   
            var checkedNodes = tree.getChecked();   
            for(var i=0;i<checkedNodes.length;i++){   
                var node = checkedNodes[i];   
                if(node.id != n.id){   
                    node.getUI().checkbox.checked = false;   
                    node.attributes.checked = false;   
                    tree.fireEvent('check', node, false);   
                }   
            }   
        }   
           
    },   
       
    // private   
    childCheck : function(node){   
        var a = node.attributes;   
        if(!a.leaf) {   
            var cs = node.childNodes;   
            var csui;   
            for(var i = 0; i < cs.length; i++) {   
                csui = cs[i].getUI();   
                if(csui.checkbox.checked ^ a.checked)   
                    csui.check(a.checked);   
            }   
        }   
    },   
       
    // private   
    parentCheck : function(node ,checked){   
        var checkbox = node.getUI().checkbox;   
        if(typeof checkbox == 'undefined')return ;   
        if(!(checked ^ checkbox.checked))return;   
        if(!checked && this.childHasChecked(node))return;   
        checkbox.checked = checked;   
        node.attributes.checked = checked;   
        node.getOwnerTree().fireEvent('check', node, checked);   
           
        var parentNode = node.parentNode;   
        if( parentNode !== null){   
            this.parentCheck(parentNode,checked);   
        }   
    },   
       
    // private   
    childHasChecked : function(node){   
        var childNodes = node.childNodes;   
        if(childNodes || childNodes.length>0){   
            for(var i=0;i<childNodes.length;i++){   
                if(childNodes[i].getUI().checkbox.checked)   
                    return true;   
            }   
        }   
        return false;   
    },   
       
    toggleCheck : function(value){   
        var cb = this.checkbox;   
        if(cb){   
            var checked = (value === undefined ? !cb.checked : value);   
            this.check(checked);   
        }   
    }   
}); 
/**
* @class Ext.tree.TreeCheckNodeUI
* @extends Ext.tree.TreeNodeUI
*
* 对 Ext.tree.TreeNodeUI 进行checkbox功能的扩展,后台返回的结点信息不用非要包含checked属性
*
* 扩展的功能点有：
* 一、支持只对树的叶子进行选择
*    只有当返回的树结点属性leaf = true 时，结点才有checkbox可选
*    使用时，只需在声明树时，加上属性 onlyLeafCheckable: true 既可，默认是false
*
* 二、支持对树的单选
*    只允许选择一个结点
*    使用时，只需在声明树时，加上属性 checkModel: "single" 既可
*
* 二、支持对树的级联多选
*    当选择结点时，自动选择该结点下的所有子结点，以及该结点的所有父结点（根结点除外），特别是支持异步，当子结点还没显示时，会从后台取得子结点，然后将其选中/取消选中
*    使用时，只需在声明树时，加上属性 checkModel: "cascade" 既可
*
* 三、添加"check"事件
*    该事件会在树结点的checkbox发生改变时触发
*    使用时，只需给树注册事件,如：
*    tree.on("check",function(node,checked){...});
*
* 默认情况下，checkModel为'multiple'，也就是多选，onlyLeafCheckable为false，所有结点都可选
*
* 使用方法：在loader里加上 baseAttrs:{uiProvider:Ext.tree.TreeCheckNodeUI} 既可.
* 例如：
*   var tree = new Ext.tree.TreePanel({
*  el:'tree-ct',
*  width:568,
*  height:300,
*  checkModel: 'cascade',   //对树的级联多选
*  onlyLeafCheckable: false,//对树所有结点都可选
*  animate: false,
*  rootVisible: false,
*  autoScroll:true,
*  loader: new Ext.tree.DWRTreeLoader({
*   dwrCall:Tmplt.getTmpltTree,
*   baseAttrs: { uiProvider: Ext.tree.TreeCheckNodeUI } //添加 uiProvider 属性
*  }),
*  root: new Ext.tree.AsyncTreeNode({ id:'0' })
* });
* tree.on("check",function(node,checked){alert(node.text+" = "+checked)}); //注册"check"事件
* tree.render();
*
*/

Ext.tree.TreeCheckNodeUI = function() {
//'multiple':多选; 'single':单选; 'cascade':级联多选
this.checkModel = 'multiple';

//only leaf can checked
this.onlyLeafCheckable = false;

Ext.tree.TreeCheckNodeUI.superclass.constructor.apply(this, arguments);
};

Ext.extend(Ext.tree.TreeCheckNodeUI, Ext.tree.TreeNodeUI, {

    renderElements : function(n, a, targetNode, bulkRender){
     var tree = n.getOwnerTree();
  this.checkModel = tree.checkModel || this.checkModel;
  this.onlyLeafCheckable = tree.onlyLeafCheckable || false;
    
        // add some indent caching, this helps performance when rendering a large tree
        this.indentMarkup = n.parentNode ? n.parentNode.ui.getChildIndent() : '';

var cb = (!this.onlyLeafCheckable || a.leaf);
        var href = a.href ? a.href : Ext.isGecko ? "" : "#";
        var buf = ['<li class="x-tree-node"><div ext:tree-node-id="',n.id,'" class="x-tree-node-el x-tree-node-leaf x-unselectable ', a.cls,'" unselectable="on">',
            '<span class="x-tree-node-indent">',this.indentMarkup,"</span>",
            '<img src="', this.emptyIcon, '" class="x-tree-ec-icon x-tree-elbow" />',
            '<img src="', a.icon || this.emptyIcon, '" class="x-tree-node-icon',(a.icon ? " x-tree-node-inline-icon" : ""),(a.iconCls ? " "+a.iconCls : ""),'" unselectable="on" />',
            cb ? ('<input class="x-tree-node-cb" type="checkbox" ' + (a.checked ? 'checked="checked" />' : '/>')) : '',
            '<a hidefocus="on" class="x-tree-node-anchor" href="',href,'" tabIndex="1" ',
             a.hrefTarget ? ' target="'+a.hrefTarget+'"' : "", '><span unselectable="on">',n.text,"</span></a></div>",
            '<ul class="x-tree-node-ct" style="display:none;"></ul>',
            "</li>"].join('');

        var nel;
        if(bulkRender !== true && n.nextSibling && (nel = n.nextSibling.ui.getEl())){
            this.wrap = Ext.DomHelper.insertHtml("beforeBegin", nel, buf);
        }else{
            this.wrap = Ext.DomHelper.insertHtml("beforeEnd", targetNode, buf);
        }
       
        this.elNode = this.wrap.childNodes[0];
        this.ctNode = this.wrap.childNodes[1];
        var cs = this.elNode.childNodes;
        this.indentNode = cs[0];
        this.ecNode = cs[1];
        this.iconNode = cs[2];
        var index = 3;
        if(cb){
            this.checkbox = cs[3];
            Ext.fly(this.checkbox).on('click', this.check.createDelegate(this,[null]));
            index++;
        }
        this.anchor = cs[index];
        this.textNode = cs[index].firstChild;
    },
   
    // private
    check : function(checked){
        var n = this.node;
  var tree = n.getOwnerTree();
  this.checkModel = tree.checkModel || this.checkModel;
 
  if( checked === null ) {
   checked = this.checkbox.checked;
  } else {
   this.checkbox.checked = checked;
  }
 
  n.attributes.checked = checked;
  tree.fireEvent('check', n, checked);
 
  if(!this.onlyLeafCheckable && this.checkModel == 'cascade'){
   var parentNode = n.parentNode;
   if(parentNode !== null) {
    this.parentCheck(parentNode,checked);
   }
   if( !n.expanded && !n.childrenRendered ) {
    n.expand(false,false,this.childCheck);
   }
   else {
    this.childCheck(n);
   }
  }else if(this.checkModel == 'single'){
   var checkedNodes = tree.getChecked();
   for(var i=0;i<checkedNodes.length;i++){
    var node = checkedNodes[i];
    if(node.id != n.id){
     node.getUI().checkbox.checked = false;
     node.attributes.checked = false;
     tree.fireEvent('check', node, false);
    }
   }
  }
       
    },
   
    // private
childCheck : function(node){
  var a = node.attributes;
  if(!a.leaf) {
   var cs = node.childNodes;
   var csui;
   for(var i = 0; i < cs.length; i++) {
    csui = cs[i].getUI();
    if(csui.checkbox.checked ^ a.checked)
     csui.check(a.checked);
   }
  }
},

// private
parentCheck : function(node ,checked){
  var checkbox = node.getUI().checkbox;
  if(typeof checkbox == 'undefined')return ;
  if(!(checked ^ checkbox.checked))return;
  if(!checked && this.childHasChecked(node))return;
  checkbox.checked = checked;
  node.attributes.checked = checked;
  node.getOwnerTree().fireEvent('check', node, checked);
 
  var parentNode = node.parentNode;
  if( parentNode !== null){
   this.parentCheck(parentNode,checked);
  }
},

// private
childHasChecked : function(node){
  var childNodes = node.childNodes;
  if(childNodes || childNodes.length>0){
   for(var i=0;i<childNodes.length;i++){
    if(childNodes[i].getUI().checkbox.checked)
     return true;
   }
  }
  return false;
},

    toggleCheck : function(value){
     var cb = this.checkbox;
        if(cb){
            var checked = (value === undefined ? !cb.checked : value);
            this.check(checked);
        }
    }
});

使用方法都在注释里了,应该已经很详细了,我就不多说了



需要注意的是, 使用例子里的Tree 使用了Ext.tree.DWRTreeLoader这个扩展类,用来加载后台树结点,这和使用其它的loader没有区别的,

如果您使用其它的loader, 同样加上baseAttrs: { uiProvider: Ext.tree.TreeCheckNodeUI }就行了