/**
* An autosuggest textbox control.
* @class
* @scope public
*/
function AutoSuggestControl(name,oTextbox /*:HTMLInputElement*/,field /*array or text*/) {
/* a name for the get parameter used in ajax request */
this.name=name;
/* the database field to fetch on th server side */
this.field=field;
/**
* The currently selected suggestions.
* @scope private
*/
this.cur /*:int*/ = -1;
/**
* The dropdown list layer.
* @scope private
*/
this.layer = null;
/**
* The textbox to capture.
* @scope private
*/
oTextbox.setAttribute("autocomplete","off");
this.textbox /*:HTMLInputElement*/ = oTextbox;
/**
* Timeout ID for fast typers.
* @scope private
*/
this.timeoutId /*:int*/ = null;
/**
* The text that the user typed.
* @scope private
*/
this.userText /*:String*/ = oTextbox.value;
this.http = zXmlHttp.createRequest();
//initialize the control
this.init();
}
/**
* Autosuggests one or more suggestions for what the user has typed.
* If no suggestions are passed in, then no autosuggest occurs.
* @scope private
* @param aSuggestions An array of suggestion strings.
* @param bTypeAhead If the control should provide a type ahead suggestion.
*/
AutoSuggestControl.prototype.autosuggest = function (aSuggestions /*:Array*/,
bTypeAhead /*:boolean*/,
searchText /*:String*/) {
//re-initialize pointer to current suggestion
this.cur = -1;
//make sure there's at least one suggestion
if (aSuggestions.length > 0 && searchText==this.textbox.value) {
if (bTypeAhead) {
this.typeAhead(aSuggestions[0]);
}
this.showSuggestions(aSuggestions);
} else {
this.hideSuggestions();
}
};
/**
* Creates the dropdown layer to display multiple suggestions.
* @scope private
*/
AutoSuggestControl.prototype.createDropDown = function () {
//FOR IE6 create iframe to place beneath the div layer
this.iframe=document.createElement("iframe");
this.iframe.style.width=(this.textbox.offsetWidth-2)+'px'; // 2 for the border
this.iframe.style.position='absolute';
this.iframe.style.display = "none";
this.iframe.setAttribute("frameBorder","0");
//this.iframe.style.filter='progid:DXImageTransform.Microsoft.Alpha(style=0,opacity=0)';
//create the layer and assign styles
this.layer = document.createElement("div");
this.layer.style.border="1px solid #AAA";
this.layer.style.position='absolute';
this.layer.style.color='#666';
this.layer.style.backgroundColor = "#FFF";
this.layer.style.visibility = "hidden";
this.layer.style.width = (this.textbox.offsetWidth-2)+'px'; // 2 for the border
this.layer.style.overflow = 'hidden';
document.body.appendChild(this.iframe);
document.body.appendChild(this.layer);
//when the user clicks on the a suggestion, get the text (innerHTML)
//and place it into a textbox
var oThis = this;
this.layer.onmousedown =
this.layer.onmouseup =
this.layer.onmouseover = function (oEvent) {
oEvent = oEvent || window.event;
oTarget = oEvent.target || oEvent.srcElement;
if (oEvent.type == "mousedown")
{
oThis.hideSuggestions();
oThis.textbox.value = oTarget.firstChild.nodeValue!=null? oTarget.firstChild.nodeValue: oThis.lastSuggestionHighlighted;
oThis.suggestionClicked=true;
} else if (oEvent.type == "mouseover") {
oThis.highlightSuggestion(oTarget);
} else {
oThis.textbox.focus();
}
};
};
/**
* Gets the left coordinate of the textbox.
* @scope private
* @return The left coordinate of the textbox in pixels.
*/
AutoSuggestControl.prototype.getLeft = function () /*:int*/ {
var oNode = this.textbox;
var iLeft = 0;
while(oNode.tagName != "BODY") {
iLeft += oNode.offsetLeft;
oNode = oNode.offsetParent;
}
return iLeft;
};
/**
* Gets the top coordinate of the textbox.
* @scope private
* @return The top coordinate of the textbox in pixels.
*/
AutoSuggestControl.prototype.getTop = function () /*:int*/ {
var oNode = this.textbox;
var iTop = 0;
while(oNode.tagName != "BODY") {
iTop += oNode.offsetTop;
oNode = oNode.offsetParent;
}
return iTop;
};
/**
* Highlights the next or previous suggestion in the dropdown and
* places the suggestion into the textbox.
* @param iDiff Either a positive or negative number indicating whether
* to select the next or previous sugggestion, respectively.
* @scope private
*/
AutoSuggestControl.prototype.goToSuggestion = function (iDiff /*:int*/) {
var cSuggestionNodes = this.layer.childNodes;
if (cSuggestionNodes.length > 0) {
var oNode = null;
if (iDiff > 0) {
if (this.cur < cSuggestionNodes.length-1) {
oNode = cSuggestionNodes[++this.cur];
}
} else {
if (this.cur > 0) {
oNode = cSuggestionNodes[--this.cur];
//alert(oNode.firstChild.nodeValue.length);
}
}
if (oNode) {
this.highlightSuggestion(oNode);
this.textbox.value = oNode.firstChild.nodeValue;
}
}
};
/**
* Handles three keydown events.
* @scope private
* @param oEvent The event object for the keydown event.
*/
AutoSuggestControl.prototype.handleKeyDown = function (oEvent /*:Event*/) {
switch(oEvent.keyCode) {
case 38: //up arrow
this.goToSuggestion(-1);
return false;
break;
case 40: //down arrow
this.goToSuggestion(1);
break;
case 27: //esc
this.textbox.value = this.userText;
//this.selectRange(this.userText.length,this.userText.length);
/* falls through */
case 13: //enter
if (this.dropDownOpen)
{
this.hideSuggestions();
oEvent.returnValue = false;
if (oEvent.preventDefault) {
oEvent.preventDefault();
}
}
break;
}
};
/**
* Handles keyup events.
* @scope private
* @param oEvent The event object for the keyup event.
*/
AutoSuggestControl.prototype.handleKeyUp = function (oEvent /*:Event*/) {
var iKeyCode = oEvent.keyCode;
var oThis = this;
//get the currently entered text
this.userText = this.textbox.value;
//for backspace (8) and delete (46), shows suggestions without typeahead
if (iKeyCode == 8 || iKeyCode == 46) {
clearTimeout(this.timeoutId);
this.timeoutId = setTimeout( function () {
oThis.requestSuggestions(oThis.userText,false);
}, 250);
//make sure not to interfere with non-character keys
} else if (iKeyCode < 32 || (iKeyCode >= 33 && iKeyCode < 46) || (iKeyCode >= 112 && iKeyCode <= 123)) {
//ignore
} else {
clearTimeout(this.timeoutId);
//request suggestions from the suggestion provider with typeahead
this.timeoutId = setTimeout( function () {
oThis.requestSuggestions(oThis.userText,true);
}, 250);
}
};
/**
* Hides the suggestion dropdown.
* @scope private
*/
AutoSuggestControl.prototype.hideSuggestions = function () {
this.dropDownOpen=false;
this.layer.style.visibility = "hidden";
this.iframe.style.display = "none";
};
/**
* Highlights the given node in the suggestions dropdown.
* @scope private
* @param oSuggestionNode The node representing a suggestion in the dropdown.
*/
AutoSuggestControl.prototype.highlightSuggestion = function (oSuggestionNode)
{
for (var i=0; i < this.layer.childNodes.length; i++)
{
var oNode = this.layer.childNodes[i];
if (oNode == oSuggestionNode)
{
oNode.style.backgroundColor = '#2F2BC8';
oNode.style.color='white';
this.lastSuggestionHighlighted=oNode.firstChild.nodeValue;
this.cur=i;
}
else
{
oNode.style.backgroundColor = '#FFF';
oNode.style.color='#666';
}
}
};
/**
* Initializes the textbox with event handlers for
* auto suggest functionality.
* @scope private
*/
AutoSuggestControl.prototype.init = function () {
//save a reference to this object
var oThis = this;
//assign the onkeyup event handler
this.textbox.onkeyup = function (oEvent) {
//check for the proper location of the event object
if (!oEvent) {
oEvent = window.event;
}
//call the handleKeyUp() method with the event object
oThis.handleKeyUp(oEvent);
};
//assign onkeydown event handler
this.textbox.onkeydown = function (oEvent) {
//check for the proper location of the event object
if (!oEvent) {
oEvent = window.event;
}
//call the handleKeyDown() method with the event object
return oThis.handleKeyDown(oEvent);
};
//assign onblur event handler (hides suggestions)
this.textbox.onblur = function ()
{
oThis.hideSuggestions();
setTimeout(
function()
{
if (oThis.suggestionClicked==false) {oThis.textbox.value=oThis.userText;}
}
,50
);
};
//create the suggestions dropdown
this.createDropDown();
};
/**
* Selects a range of text in the textbox.
* @scope public
* @param iStart The start index (base 0) of the selection.
* @param iEnd The end index of the selection.
*/
AutoSuggestControl.prototype.selectRange = function (iStart /*:int*/, iEnd /*:int*/) {
//use text ranges for Internet Explorer
if (this.textbox.createTextRange) {
var oRange = this.textbox.createTextRange();
oRange.moveStart("character", iStart);
oRange.moveEnd("character", iEnd - this.textbox.value.length);
oRange.select();
//use setSelectionRange() for Mozilla
} else if (this.textbox.setSelectionRange) {
this.textbox.setSelectionRange(iStart, iEnd);
}
//set focus back to the textbox
this.textbox.focus();
};
/**
* Builds the suggestion layer contents, moves it into position,
* and displays the layer.
* @scope private
* @param aSuggestions An array of suggestions for the control.
*/
AutoSuggestControl.prototype.showSuggestions = function (aSuggestions /*:Array*/) {
var oDiv = null;
this.layer.innerHTML = ""; //clear contents of the layer
this.lastSuggestionHighlighted=this.userText; //for IE6 - set the last selected suggestion as empty
this.suggestionClicked=false; //indicate if the onblur is caused by a clicking of a suggestion or not
this.dropDownOpen=true;
for (var i=0; i < aSuggestions.length; i++) {
oDiv = document.createElement("div");
//oDiv.appendChild(document.createTextNode(aSuggestions[i]));
oDiv.innerHTML=aSuggestions[i];
oDiv.style.paddingLeft='4px';
oDiv.style.paddingRight='4px';
oDiv.style.paddingTop='2px';
oDiv.style.paddingBottom='2px';
oDiv.style.cursor= "default";
this.layer.appendChild(oDiv);
}
this.layer.style.left = this.getLeft() + "px";
this.layer.style.top = (this.getTop()+this.textbox.offsetHeight) + "px";
this.layer.style.visibility = "visible";
this.iframe.style.left = this.getLeft() + "px";
this.iframe.style.top = (this.getTop()+this.textbox.offsetHeight) + "px";
this.iframe.style.display = "block";
this.iframe.style.height = this.layer.offsetHeight + "px";
};
/**
* Inserts a suggestion into the textbox, highlighting the
* suggested part of the text.
* @scope private
* @param sSuggestion The suggestion for the textbox.
*/
AutoSuggestControl.prototype.typeAhead = function (sSuggestion /*:String*/) {
//check for support of typeahead functionality
if (this.textbox.createTextRange || this.textbox.setSelectionRange)
{
var iLen = this.textbox.value.length;
this.textbox.value = sSuggestion.replace(/&/g,'&').replace(/>/g,'>').replace(/</g,'<');
this.selectRange(iLen, sSuggestion.length);
}
};
/**
* Request suggestions for the given autosuggest control.
* @scope protected
* @param oAutoSuggestControl The autosuggest control to provide suggestions for.
*/
AutoSuggestControl.prototype.requestSuggestions = function (searchText,bTypeAhead /*:boolean*/) {
if (searchText=='')
{
this.hideSuggestions();
return false;
}
var oHttp = this.http;
var oThis=this;
//cancel any active requests
if (oHttp.readyState != 0) {
oHttp.abort();
}
href=location.href.indexOf('#')==-1?location.href:location.href.substr(0,location.href.indexOf('#'));
href=href.indexOf('?')==-1?href+'?':href;
href=href+'&'+this.name+'_suggestText='+escape(searchText);
if (typeof(this.field)=='object')
for (i=0;i<this.field.length;i++)
href=href+'&'+this.name+'_suggestField[]='+this.field[i];
else
href=href+'&'+this.name+'_suggestField[]='+this.field;
//alert(href);
oHttp.open("get", href, true);
oHttp.onreadystatechange = function ()
{
if (oHttp.readyState == 4)
{
//if (oHttp.status == 200)
//{
//evaluate the returned text JavaScript (an array)
var aSuggestions = oHttp.responseText!=''?oHttp.responseText.split("-###-"):Array();
//provide suggestions to the control
oThis.autosuggest(aSuggestions,bTypeAhead,searchText);
//}
//else oThis.requestSuggestions(searchText,bTypeAhead);
}
};
//send the request
oHttp.send(null);
};
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