extjs+s2sh实现异步Tree的节点搜索和查找下一个(FindNext)

本文讨论了treefilter实现tree的查询，和后台返回路径的方式，来实现对extjs tree的搜索。

介绍部分内容来源网络，先谢谢该作者。

在任何一个Tree树中，提供查找功能无疑会大大方便用户。不用睁大眼睛一级一级去展开，只要输入关键字，回车就能自动定位到节点，岂不快哉？然后再次回车查找下一个。这样的用户体验是相当完美的 ( 见《用户体验这点事儿》)。但在动态异步加载的Tree树中，客户端实现这样的功能就有点困难，因为节点是异步动态加载的。默认是没有全部从服务器端取回的，通常的做法是默认加载第一级，其他级的节点都是惰性按需加载的，用户点了才会展开。而对于这个没有完全加载的树，用户希望搜索节点，怎么实现？笨办法是先展开树的所有节点，然后再在树中搜索。这样的话在服务器数据量大的情况下会非常慢。这里的实现方法是在服务器端的WebService查找，通过AJAX返回第一个匹配节点的路径Path，然后展开这个路径，选中这个搜索到节点。查找下一个（FindNext）的实现方法是…



(提供查找功能的树Tree无疑会大大方便用户)
在任何一个Tree树中，提供查找功能无疑会大大方便用户。不用睁大眼睛一级一级去展开，只要输入关键字，回车就能自动定位到节点，岂不快哉？然后再次回车查找下一个。这样的用户体验是相当完美的。

但在动态异步加载的Tree树中，客户端实现这样的功能就有点困难，因为节点是异步动态加载的。默认是没有全部从服务器端取回的，通常的做法是默认加载第一级，其他级的节点都是惰性按需加载的，用户点了才会展开。而对于这个没有完全加载的树，用户希望搜索节点，怎么实现？笨办法是先展开树的所有节点，然后再在树中搜索。这样的话在服务器数据量大的情况下会非常慢。

这里的实现方法是在服务器端的WebService查找，通过AJAX返回第一个匹配节点的路径Path，然后展开这个路径，选中这个搜索到节点。

在ExtJS中，AsyncTreeNode是异步节点，TreeLoader实现对树结点的异步加载，即使服务器取到大量的数据，也没有问题，异步加载能保证性能和节点的按需加载。服务端需要生成指定格式的Json字符串。

首先这儿有一个extjs的动态树，默认加载第一级，其他的级按需加载。（由于工程文件太大，s2sh+oracle，后台代码不提供。）下面给出利用treefilter和返回展开路径的web端代码：
dymicTree是一个treePanel，动态树。

var timeOutId = null;
/**
* 定义一个treefilter，采用第一种方式对动态树进行过滤，当然首先要展开树
* @author centre
*/
var treeFilter = new Ext.tree.TreeFilter(dymicTree, {
clearBlank : true,
autoClear : true
});
// 保存上次隐藏的空节点
var hiddenPkgs = [];
/**
* 通过关键字查找树的节点，并定位，这儿有2种实现方式， 1.通过treeFilter，当数据量小的时候是可行的 2.通过返回tree路径，对应数据量大的时候
*
* @param {}
*            node
* @param {}
*            event
* @author centre
*/

var findByKeyWordFiler = function(node, event) {

// 清除timeOutId
clearTimeout(timeOutId);

// 展开树节点
dymicTree.expandAll();
// 为了避免重复的访问后台，给服务器造成的压力，采用timeOutId进行控制，如果采用treeFilter也可以造成重复的keyup
timeOutId = setTimeout(function() {
// 获取输入框的值。
var text = node.getValue();
// 根据输入制作一个正则表达式，'i'代表不区分大小写
var re = new RegExp(Ext.escapeRe(text), 'i');
// 先要显示上次隐藏掉的节点
Ext.each(hiddenPkgs, function(n) {
n.ui.show();
});
hiddenPkgs = [];
if (text != "") {

treeFilter.filterBy(function(n) {
// 只过滤叶子节点，这样省去枝干被过滤的时候，底下的叶子都无法显示
return !n.isLeaf() || re.test(n.text);
});
// 如果这个节点不是叶子，而且下面没有子节点，就应该隐藏掉
dymicTree.root.cascade(function(n) {
if(n.id!='0'){
if(!n.isLeaf() &&judge(n,re)==false&& !re.test(n.text)){
hiddenPkgs.push(n);
n.ui.hide();
}
}
});

} else {
treeFilter.clear();
return;
}

}, 500);
}

//过滤不匹配的非叶子节点或者是叶子节点
/**
*
* @param {Object} n
* @param {Object} re
* @return {TypeName}
* @author yang
*/
var judge =function(n,re){
var str=false;
n.cascade(function(n1){
if(n1.isLeaf())
{
if(re.test(n1.text)){str=true;return;}
}
else{

if(re.test(n1.text)){str=true;return;}
}
});

return str;
};
/**
* 根据路径展开节点后，选中该节点
* @param {} bSuccess
* @param {} oLastNode
*/
function onExpandPathComplete(bSuccess, oLastNode) {
if (!bSuccess)
return;
// focus 节点，并选中节点！
selectNode(oLastNode);
}

/**
* 选中传入的节点，并单击此节点
*
* @param {}
*            node 传入节点对象
* @author centre
*/
var selectNode = function(node) {
node.ensureVisible();
node.select();
node.fireEvent('click', node);
}
/**
* 通过关键字查找树的节点，并定位，这儿有2种实现方式， 1.通过treeFilter，当数据量小的时候是可行的 2.通过返回tree路径，对应数据量大的时候
* 支持模糊查询
*
* @param {}
*            node
* @param {}
*            event
* @author centre
*/
var findByKeyWordPath = function(node, event) {
// 清除timeOutId
clearTimeout(timeOutId);
timeOutId = setTimeout(function() {
// 获取输入框的值。
var text = node.getValue().trim();
// 采用ajax获得需要展开的路径
if (text != "") {
Ext.Ajax.request({
url : 'jsps/servlet/findByKeyword.jsp',
success : function(response, opts) {
var obj = Ext.decode(response.responseText);
var length = obj.record.length;
dymicTree.root.reload();
for (var i = 0; i < length; i++) {
var path = obj.record[i].path;
dymicTree.expandPath(path,'id',onExpandPathComplete);
}
},
failure : function(response, opts) {
Ext.Msg.alert("错误提示", "请求失败,请与开发人员联系。")
.setIcon(Ext.MessageBox.ERROR);
},
params : {
keyWord : text
}
});
} else {
// Ext.Msg.alert("信息",
// "请输入关键字").setIcon(Ext.MessageBox.INFO);
// return;
}
}, 500);
}

/**
* 给输入框绑定keyup事件，需要加上enableKeyEvents:true才能让extjs的textfield代理 鼠标事件
*
* @author centre
*/

searchBox.findById("keyWord").on("keyup", function(node, event) {
findByKeyWordFiler(node, event);
});

以下是extjs官方帮助文档的代码，可以参考：

Ext.BLANK_IMAGE_URL = 'resources/s.gif';

Docs = {};

ApiPanel = function() {
ApiPanel.superclass.constructor.call(this, {
id:'api-tree',
region:'west',
split:true,
header: false,
width: 280,
minSize: 175,
maxSize: 500,
collapsible: true,
margins:'0 0 5 5',
cmargins:'0 0 0 0',
rootVisible:false,
lines:false,
autoScroll:true,
animCollapse:false,
animate: false,
collapseMode:'mini',
loader: new Ext.tree.TreeLoader({
preloadChildren: true,
clearOnLoad: false
}),
root: new Ext.tree.AsyncTreeNode({
text:'Ext JS',
id:'root',
expanded:true,
children:[Docs.classData]
}),
collapseFirst:false
});
// no longer needed!
//new Ext.tree.TreeSorter(this, {folderSort:true,leafAttr:'isClass'});

this.getSelectionModel().on('beforeselect', function(sm, node){
return node.isLeaf();
});
};

Ext.extend(ApiPanel, Ext.tree.TreePanel, {
initComponent: function(){
this.hiddenPkgs = [];
Ext.apply(this, {
tbar:[ ' ',
new Ext.form.TextField({
width: 200,
emptyText:'Find a Class',
enableKeyEvents: true,
listeners:{
render: function(f){
this.filter = new Ext.tree.TreeFilter(this, {
clearBlank: true,
autoClear: true
});
},
keydown: {
fn: this.filterTree,
buffer: 350,
scope: this
},
scope: this
}
}), ' ', ' ',
{
iconCls: 'icon-expand-all',
tooltip: 'Expand All',
handler: function(){ this.root.expand(true); },
scope: this
}, '-', {
iconCls: 'icon-collapse-all',
tooltip: 'Collapse All',
handler: function(){ this.root.collapse(true); },
scope: this
}]
})
ApiPanel.superclass.initComponent.call(this);
},
filterTree: function(t, e){
var text = t.getValue();
Ext.each(this.hiddenPkgs, function(n){
n.ui.show();
});
if(!text){
this.filter.clear();
return;
}
this.expandAll();

var re = new RegExp('^' + Ext.escapeRe(text), 'i');
this.filter.filterBy(function(n){
return !n.attributes.isClass || re.test(n.text);
});

// hide empty packages that weren't filtered
this.hiddenPkgs = [];
var me = this;
this.root.cascade(function(n){
if(!n.attributes.isClass && n.ui.ctNode.offsetHeight < 3){
n.ui.hide();
me.hiddenPkgs.push(n);
}
});
},
selectClass : function(cls){
if(cls){
var parts = cls.split('.');
var last = parts.length-1;
var res = [];
var pkg = [];
for(var i = 0; i < last; i++){ // things get nasty - static classes can have .
var p = parts[i];
var fc = p.charAt(0);
var staticCls = fc.toUpperCase() == fc;
if(p == 'Ext' || !staticCls){
pkg.push(p);
res[i] = 'pkg-'+pkg.join('.');
}else if(staticCls){
--last;
res.splice(i, 1);
}
}
res[last] = cls;

this.selectPath('/root/apidocs/'+res.join('/'));
}
}
});

DocPanel = Ext.extend(Ext.Panel, {
closable: true,
autoScroll:true,

initComponent : function(){
var ps = this.cclass.split('.');
this.title = ps[ps.length-1];
Ext.apply(this,{
tbar: ['->',{
text: 'Config Options',
handler: this.scrollToMember.createDelegate(this, ['configs']),
iconCls: 'icon-config'
},'-',{
text: 'Properties',
handler: this.scrollToMember.createDelegate(this, ['props']),
iconCls: 'icon-prop'
}, '-',{
text: 'Methods',
handler: this.scrollToMember.createDelegate(this, ['methods']),
iconCls: 'icon-method'
}, '-',{
text: 'Events',
handler: this.scrollToMember.createDelegate(this, ['events']),
iconCls: 'icon-event'
}, '-',{
text: 'Direct Link',
handler: this.directLink,
scope: this,
iconCls: 'icon-fav'
}, '-',{
tooltip:'Hide Inherited Members',
iconCls: 'icon-hide-inherited',
enableToggle: true,
scope: this,
toggleHandler : function(b, pressed){
this.body[pressed ? 'addClass' : 'removeClass']('hide-inherited');
}
}, '-', {
tooltip:'Expand All Members',
iconCls: 'icon-expand-members',
enableToggle: true,
scope: this,
toggleHandler : function(b, pressed){
this.body[pressed ? 'addClass' : 'removeClass']('full-details');
}
}]
});
DocPanel.superclass.initComponent.call(this);
},

directLink : function(){
var link = String.format(
"<a href=\"{0}\" target=\"_blank\">{0}</a>",
document.location.href+'?class='+this.cclass
);
Ext.Msg.alert('Direct Link to ' + this.cclass,link);
},

scrollToMember : function(member){
var el = Ext.fly(this.cclass + '-' + member);
if(el){
var top = (el.getOffsetsTo(this.body)[1]) + this.body.dom.scrollTop;
this.body.scrollTo('top', top-25, {duration:0.75, callback: this.hlMember.createDelegate(this, [member])});
}
},

scrollToSection : function(id){
var el = Ext.getDom(id);
if(el){
var top = (Ext.fly(el).getOffsetsTo(this.body)[1]) + this.body.dom.scrollTop;
this.body.scrollTo('top', top-25, {duration:0.5, callback: function(){
Ext.fly(el).next('h2').pause(0.2).highlight('#8DB2E3', {attr:'color'});
}});
}
},

hlMember : function(member){
var el = Ext.fly(this.cclass + '-' + member);
if(el){
if (tr = el.up('tr')) {
tr.highlight('#cadaf9');
}
}
}
});

MainPanel = function(){

this.searchStore = new Ext.data.Store({
proxy: new Ext.data.ScriptTagProxy({
url: 'http://extjs.com/playpen/api.php'
}),
reader: new Ext.data.JsonReader({
root: 'data'
},
['cls', 'member', 'type', 'doc']
),
baseParams: {},
listeners: {
'beforeload' : function(){
this.baseParams.qt = Ext.getCmp('search-type').getValue();
}
}
});

MainPanel.superclass.constructor.call(this, {
id:'doc-body',
region:'center',
margins:'0 5 5 0',
resizeTabs: true,
minTabWidth: 135,
tabWidth: 135,
plugins: new Ext.ux.TabCloseMenu(),
enableTabScroll: true,
activeTab: 0,

items: {
id:'welcome-panel',
title: 'API Home',
autoLoad: {url: 'welcome.html', callback: this.initSearch, scope: this},
iconCls:'icon-docs',
autoScroll: true,
tbar: [
'Search: ', ' ',
new Ext.ux.SelectBox({
listClass:'x-combo-list-small',
width:90,
value:'Starts with',
id:'search-type',
store: new Ext.data.SimpleStore({
fields: ['text'],
expandData: true,
data : ['Starts with', 'Ends with', 'Any match']
}),
displayField: 'text'
}), ' ',
new Ext.app.SearchField({
width:240,
store: this.searchStore,
paramName: 'q'
})
]
}
});
};

Ext.extend(MainPanel, Ext.TabPanel, {

initEvents : function(){
MainPanel.superclass.initEvents.call(this);
this.body.on('click', this.onClick, this);
},

onClick: function(e, target){
if(target = e.getTarget('a:not(.exi)', 3)){
var cls = Ext.fly(target).getAttributeNS('ext', 'cls');
e.stopEvent();
if(cls){
var member = Ext.fly(target).getAttributeNS('ext', 'member');
this.loadClass(target.href, cls, member);
}else if(target.className == 'inner-link'){
this.getActiveTab().scrollToSection(target.href.split('#')[1]);
}else{
window.open(target.href);
}
}else if(target = e.getTarget('.micon', 2)){
e.stopEvent();
var tr = Ext.fly(target.parentNode);
if(tr.hasClass('expandable')){
tr.toggleClass('expanded');
}
}
},

loadClass : function(href, cls, member){
var id = 'docs-' + cls;
var tab = this.getComponent(id);
if(tab){
this.setActiveTab(tab);
if(member){
tab.scrollToMember(member);
}
}else{
var autoLoad = {url: href};
if(member){
autoLoad.callback = function(){
Ext.getCmp(id).scrollToMember(member);
}
}
var p = this.add(new DocPanel({
id: id,
cclass : cls,
autoLoad: autoLoad,
iconCls: Docs.icons[cls]
}));
this.setActiveTab(p);
}
},

initSearch : function(){
// Custom rendering Template for the View
var resultTpl = new Ext.XTemplate(
'<tpl for=".">',
'<div class="search-item">',
'<a class="member" ext:cls="{cls}" ext:member="{member}" href="output/{cls}.html">',
'<img src="../resources/images/default/s.gif" class="item-icon icon-{type}"/>{member}',
'</a> ',
'<a class="cls" ext:cls="{cls}" href="output/{cls}.html">{cls}</a>',
'<p>{doc}</p>',
'</div></tpl>'
);

var p = new Ext.DataView({
applyTo: 'search',
tpl: resultTpl,
loadingText:'Searching...',
store: this.searchStore,
itemSelector: 'div.search-item',
emptyText: '<h3>Use the search field above to search the Ext API for classes, properties, config options, methods and events.</h3>'
});
},

doSearch : function(e){
var k = e.getKey();
if(!e.isSpecialKey()){
var text = e.target.value;
if(!text){
this.searchStore.baseParams.q = '';
this.searchStore.removeAll();
}else{
this.searchStore.baseParams.q = text;
this.searchStore.reload();
}
}
}
});

Ext.onReady(function(){

Ext.QuickTips.init();

var api = new ApiPanel();
var mainPanel = new MainPanel();

api.on('click', function(node, e){
if(node.isLeaf()){
e.stopEvent();
mainPanel.loadClass(node.attributes.href, node.id);
}
});

mainPanel.on('tabchange', function(tp, tab){
api.selectClass(tab.cclass);
});

var viewport = new Ext.Viewport({
layout:'border',
items:[ {
cls: 'docs-header',
height: 44,
region:'north',
xtype:'box',
el:'header',
border:false,
margins: '0 0 5 0'
}, api, mainPanel ]
});

api.expandPath('/root/apidocs');

// allow for link in
var page = window.location.href.split('?')[1];
if(page){
var ps = Ext.urlDecode(page);
var cls = ps['class'];
mainPanel.loadClass('output/' + cls + '.html', cls, ps.member);
}

viewport.doLayout();

setTimeout(function(){
Ext.get('loading').remove();
Ext.get('loading-mask').fadeOut({remove:true});
}, 250);

});

Ext.app.SearchField = Ext.extend(Ext.form.TwinTriggerField, {
initComponent : function(){
if(!this.store.baseParams){
this.store.baseParams = {};
}
Ext.app.SearchField.superclass.initComponent.call(this);
this.on('specialkey', function(f, e){
if(e.getKey() == e.ENTER){
this.onTrigger2Click();
}
}, this);
},

validationEvent:false,
validateOnBlur:false,
trigger1Class:'x-form-clear-trigger',
trigger2Class:'x-form-search-trigger',
hideTrigger1:true,
width:180,
hasSearch : false,
paramName : 'query',

onTrigger1Click : function(){
if(this.hasSearch){
this.store.baseParams[this.paramName] = '';
this.store.removeAll();
this.el.dom.value = '';
this.triggers[0].hide();
this.hasSearch = false;
this.focus();
}
},

onTrigger2Click : function(){
var v = this.getRawValue();
if(v.length < 1){
this.onTrigger1Click();
return;
}
if(v.length < 2){
Ext.Msg.alert('Invalid Search', 'You must enter a minimum of 2 characters to search the API');
return;
}
this.store.baseParams[this.paramName] = v;
var o = {start: 0};
this.store.reload({params:o});
this.hasSearch = true;
this.triggers[0].show();
this.focus();
}
});

/**
* Makes a ComboBox more closely mimic an HTML SELECT.  Supports clicking and dragging
* through the list, with item selection occurring when the mouse button is released.
* When used will automatically set {@link #editable} to false and call {@link Ext.Element#unselectable}
* on inner elements.  Re-enabling editable after calling this will NOT work.
*
* @author Corey Gilmore
* http://extjs.com/forum/showthread.php?t=6392 *
* @history 2007-07-08 jvs
* Slight mods for Ext 2.0
*/
Ext.ux.SelectBox = function(config){
this.searchResetDelay = 1000;
config = config || {};
config = Ext.apply(config || {}, {
editable: false,
forceSelection: true,
rowHeight: false,
lastSearchTerm: false,
triggerAction: 'all',
mode: 'local'
});

Ext.ux.SelectBox.superclass.constructor.apply(this, arguments);

this.lastSelectedIndex = this.selectedIndex || 0;
};

Ext.extend(Ext.ux.SelectBox, Ext.form.ComboBox, {
lazyInit: false,
initEvents : function(){
Ext.ux.SelectBox.superclass.initEvents.apply(this, arguments);
// you need to use keypress to capture upper/lower case and shift+key, but it doesn't work in IE
this.el.on('keydown', this.keySearch, this, true);
this.cshTask = new Ext.util.DelayedTask(this.clearSearchHistory, this);
},

keySearch : function(e, target, options) {
var raw = e.getKey();
var key = String.fromCharCode(raw);
var startIndex = 0;

if( !this.store.getCount() ) {
return;
}

switch(raw) {
case Ext.EventObject.HOME:
e.stopEvent();
this.selectFirst();
return;

case Ext.EventObject.END:
e.stopEvent();
this.selectLast();
return;

case Ext.EventObject.PAGEDOWN:
this.selectNextPage();
e.stopEvent();
return;

case Ext.EventObject.PAGEUP:
this.selectPrevPage();
e.stopEvent();
return;
}

// skip special keys other than the shift key
if( (e.hasModifier() && !e.shiftKey) || e.isNavKeyPress() || e.isSpecialKey() ) {
return;
}
if( this.lastSearchTerm == key ) {
startIndex = this.lastSelectedIndex;
}
this.search(this.displayField, key, startIndex);
this.cshTask.delay(this.searchResetDelay);
},

onRender : function(ct, position) {
this.store.on('load', this.calcRowsPerPage, this);
Ext.ux.SelectBox.superclass.onRender.apply(this, arguments);
if( this.mode == 'local' ) {
this.calcRowsPerPage();
}
},

onSelect : function(record, index, skipCollapse){
if(this.fireEvent('beforeselect', this, record, index) !== false){
this.setValue(record.data[this.valueField || this.displayField]);
if( !skipCollapse ) {
this.collapse();
}
this.lastSelectedIndex = index + 1;
this.fireEvent('select', this, record, index);
}
},

render : function(ct) {
Ext.ux.SelectBox.superclass.render.apply(this, arguments);
if( Ext.isSafari ) {
this.el.swallowEvent('mousedown', true);
}
this.el.unselectable();
this.innerList.unselectable();
this.trigger.unselectable();
this.innerList.on('mouseup', function(e, target, options) {
if( target.id && target.id == this.innerList.id ) {
return;
}
this.onViewClick();
}, this);

this.innerList.on('mouseover', function(e, target, options) {
if( target.id && target.id == this.innerList.id ) {
return;
}
this.lastSelectedIndex = this.view.getSelectedIndexes()[0] + 1;
this.cshTask.delay(this.searchResetDelay);
}, this);

this.trigger.un('click', this.onTriggerClick, this);
this.trigger.on('mousedown', function(e, target, options) {
e.preventDefault();
this.onTriggerClick();
}, this);

this.on('collapse', function(e, target, options) {
Ext.getDoc().un('mouseup', this.collapseIf, this);
}, this, true);

this.on('expand', function(e, target, options) {
Ext.getDoc().on('mouseup', this.collapseIf, this);
}, this, true);
},

clearSearchHistory : function() {
this.lastSelectedIndex = 0;
this.lastSearchTerm = false;
},

selectFirst : function() {
this.focusAndSelect(this.store.data.first());
},

selectLast : function() {
this.focusAndSelect(this.store.data.last());
},

selectPrevPage : function() {
if( !this.rowHeight ) {
return;
}
var index = Math.max(this.selectedIndex-this.rowsPerPage, 0);
this.focusAndSelect(this.store.getAt(index));
},

selectNextPage : function() {
if( !this.rowHeight ) {
return;
}
var index = Math.min(this.selectedIndex+this.rowsPerPage, this.store.getCount() - 1);
this.focusAndSelect(this.store.getAt(index));
},

search : function(field, value, startIndex) {
field = field || this.displayField;
this.lastSearchTerm = value;
var index = this.store.find.apply(this.store, arguments);
if( index !== -1 ) {
this.focusAndSelect(index);
}
},

focusAndSelect : function(record) {
var index = typeof record === 'number' ? record : this.store.indexOf(record);
this.select(index, this.isExpanded());
this.onSelect(this.store.getAt(record), index, this.isExpanded());
},

calcRowsPerPage : function() {
if( this.store.getCount() ) {
this.rowHeight = Ext.fly(this.view.getNode(0)).getHeight();
this.rowsPerPage = this.maxHeight / this.rowHeight;
} else {
this.rowHeight = false;
}
}

});

Ext.Ajax.on('requestcomplete', function(ajax, xhr, o){
if(typeof urchinTracker == 'function' && o && o.url){
urchinTracker(o.url);
}
});