https://lucknowsmartcity.com/js/autosuggest2.js

1
2
3/**
4 * An autosuggest textbox control.
5 * @class
6 * @scope public
7 */
8function AutoSuggestControl(oTextbox /*:HTMLInputElement*/, 
9                            oProvider /*:SuggestionProvider*/) {
10    
11    /**
12     * The currently selected suggestions.
13     * @scope private
14     */   
15    this.cur /*:int*/ = -1;
16
17    /**
18     * The dropdown list layer.
19     * @scope private
20     */
21    this.layer = null;
22    
23    /**
24     * Suggestion provider for the autosuggest feature.
25     * @scope private.
26     */
27    this.provider /*:SuggestionProvider*/ = oProvider;
28    
29    /**
30     * The textbox to capture.
31     * @scope private
32     */
33    this.textbox /*:HTMLInputElement*/ = oTextbox;
34    
35    //initialize the control
36    this.init();
37    
38}
39
40/**
41 * Autosuggests one or more suggestions for what the user has typed.
42 * If no suggestions are passed in, then no autosuggest occurs.
43 * @scope private
44 * @param aSuggestions An array of suggestion strings.
45 * @param bTypeAhead If the control should provide a type ahead suggestion.
46 */
47AutoSuggestControl.prototype.autosuggest = function (aSuggestions /*:Array*/,
48                                                     bTypeAhead /*:boolean*/) {
49    //make sure there's at least one suggestion
50    if (aSuggestions.length > 0) {
51        if (bTypeAhead) {
52           this.typeAhead(aSuggestions[0]);
53        }
54        
55        this.showSuggestions(aSuggestions);
56    } else {
57        this.hideSuggestions();
58    }
59};
60
61/**
62 * Creates the dropdown layer to display multiple suggestions.
63 * @scope private
64 */
65AutoSuggestControl.prototype.createDropDown = function () {
66    var oThis = this;
67
68    //create the layer and assign styles
69    this.layer = document.createElement("div");
70    this.layer.className = "suggestions";
71    this.layer.style.visibility = "hidden";
72    this.layer.style.width ='300px';
73    
74    //when the user clicks on the a suggestion, get the text (innerHTML)
75    //and place it into a textbox
76    this.layer.onmousedown = 
77    this.layer.onmouseup = 
78    this.layer.onmouseover = function (oEvent) {
79        oEvent = oEvent || window.event;
80        oTarget = oEvent.target || oEvent.srcElement;
81
82        if (oEvent.type == "mousedown") {
83            oThis.textbox.value = oTarget.firstChild.nodeValue;
84            oThis.hideSuggestions();
85        } else if (oEvent.type == "mouseover") {
86            oThis.highlightSuggestion(oTarget);
87        } else {
88            oThis.textbox.focus();
89        }
90    };
91    
92    
93    document.body.appendChild(this.layer);
94};
95
96/**
97 * Gets the left coordinate of the textbox.
98 * @scope private
99 * @return The left coordinate of the textbox in pixels.
100 */
101AutoSuggestControl.prototype.getLeft = function () /*:int*/ {
102
103    var oNode = this.textbox;
104    var iLeft = 0;
105    
106    while(oNode.tagName != "BODY") {
107        iLeft += oNode.offsetLeft;
108        oNode = oNode.offsetParent;        
109    }
110    
111    return iLeft;
112};
113
114/**
115 * Gets the top coordinate of the textbox.
116 * @scope private
117 * @return The top coordinate of the textbox in pixels.
118 */
119AutoSuggestControl.prototype.getTop = function () /*:int*/ {
120    var oNode = this.textbox;
121    var iTop = 0;
122    
123    while(oNode.tagName != "BODY") {
124        iTop += oNode.offsetTop;
125        oNode = oNode.offsetParent;
126    }
127    
128    return iTop;
129};
130
131/**
132 * Handles three keydown events.
133 * @scope private
134 * @param oEvent The event object for the keydown event.
135 */
136AutoSuggestControl.prototype.handleKeyDown = function (oEvent /*:Event*/) {
137    switch(oEvent.keyCode) {
138        case 38: //up arrow
139            this.previousSuggestion();
140            break;
141        case 40: //down arrow 
142            this.nextSuggestion();
143            break;
144        case 13: //enter
145            this.hideSuggestions();
146            break;
147    }
148
149};
150
151/**
152 * Handles keyup events.
153 * @scope private
154 * @param oEvent The event object for the keyup event.
155 */
156AutoSuggestControl.prototype.handleKeyUp = function (oEvent /*:Event*/) {
157    var iKeyCode = oEvent.keyCode;
158
159    //for backspace (8) and delete (46), shows suggestions without typeahead
160   
161	if (iKeyCode == 8 || iKeyCode == 46 ) {
162		
163        this.provider.requestSuggestions(this, false);
164        
165    //make sure not to interfere with non-character keys
166    } else if (iKeyCode < 32 || (iKeyCode >= 33 && iKeyCode < 46) || (iKeyCode >= 112 && iKeyCode <= 123)) {
167		
168        //ignore
169    } else {
170		
171        //request suggestions from the suggestion provider with typeahead
172        this.provider.requestSuggestions(this, true);
173
174    }
175};
176
177/**
178 * Hides the suggestion dropdown.
179 * @scope private
180 */
181AutoSuggestControl.prototype.hideSuggestions = function () {
182    this.layer.style.visibility = "hidden";
183};
184
185/**
186 * Highlights the given node in the suggestions dropdown.
187 * @scope private
188 * @param oSuggestionNode The node representing a suggestion in the dropdown.
189 */
190AutoSuggestControl.prototype.highlightSuggestion = function (oSuggestionNode) {
191    for (var i=0; i < this.layer.childNodes.length; i++) {
192        var oNode = this.layer.childNodes[i];

193        if (oNode == oSuggestionNode) {
194            oNode.className = "current"
195        } else if (oNode.className == "current") {
196            oNode.className = "";
197        }
198    }
199};
200
201/**
202 * Initializes the textbox with event handlers for
203 * auto suggest functionality.
204 * @scope private
205 */
206AutoSuggestControl.prototype.init = function () {
207    //save a reference to this object
208    var oThis = this;
209   
210    //assign the onkeyup event handler
211    this.textbox.onkeyup = function (oEvent) {
212   
213        //check for the proper location of the event object
214        if (!oEvent) {
215			
216            oEvent = window.event;
217        }    
218        
219        //call the handleKeyUp() method with the event object
220		
221        oThis.handleKeyUp(oEvent);
222    };
223    
224    //assign onkeydown event handler
225    this.textbox.onkeydown = function (oEvent) {
226    
227        //check for the proper location of the event object
228        if (!oEvent) {
229            oEvent = window.event;
230        }    
231        
232        //call the handleKeyDown() method with the event object
233        oThis.handleKeyDown(oEvent);
234    };
235    
236    //assign onblur event handler (hides suggestions)    
237    this.textbox.onblur = function () {
238        oThis.hideSuggestions();
239		//checkValid();
240		
241		//getNubApp();
242		
243		//getMaterialId();
244    };    
245    
246    //create the suggestions dropdown
247    this.createDropDown();
248};
249
250/**
251 * Highlights the next suggestion in the dropdown and
252 * places the suggestion into the textbox.
253 * @scope private
254 */
255AutoSuggestControl.prototype.nextSuggestion = function () {
256    var cSuggestionNodes = this.layer.childNodes;
257
258    if (cSuggestionNodes.length > 0 && this.cur < cSuggestionNodes.length-1) {
259        var oNode = cSuggestionNodes[++this.cur];
260        this.highlightSuggestion(oNode);
261        this.textbox.value = oNode.firstChild.nodeValue; 
262    }
263};
264
265/**
266 * Highlights the previous suggestion in the dropdown and
267 * places the suggestion into the textbox.
268 * @scope private
269 */
270AutoSuggestControl.prototype.previousSuggestion = function () {
271    var cSuggestionNodes = this.layer.childNodes;
272
273    if (cSuggestionNodes.length > 0 && this.cur > 0) {
274        var oNode = cSuggestionNodes[--this.cur];
275        this.highlightSuggestion(oNode);
276        this.textbox.value = oNode.firstChild.nodeValue;   
277    }
278};
279
280/**
281 * Selects a range of text in the textbox.
282 * @scope public
283 * @param iStart The start index (base 0) of the selection.
284 * @param iLength The number of characters to select.
285 */
286AutoSuggestControl.prototype.selectRange = function (iStart /*:int*/, iLength /*:int*/) {
287    //use text ranges for Internet Explorer
288    if (this.textbox.createTextRange) {
289        var oRange = this.textbox.createTextRange(); 
290        oRange.moveStart("character", iStart); 
291        oRange.moveEnd("character", iLength - this.textbox.value.length);      
292        oRange.select();
293        
294    //use setSelectionRange() for Mozilla
295    } else if (this.textbox.setSelectionRange) {
296        this.textbox.setSelectionRange(iStart, iLength);
297    }     
298
299    //set focus back to the textbox
300    this.textbox.focus();      
301}; 
302
303/**
304 * Builds the suggestion layer contents, moves it into position,
305 * and displays the layer.
306 * @scope private
307 * @param aSuggestions An array of suggestions for the control.
308 */
309AutoSuggestControl.prototype.showSuggestions = function (aSuggestions /*:Array*/) {
310    var oDiv = null;
311    this.layer.innerHTML = "";  //clear contents of the layer
312    
313    for (var i=0; i < aSuggestions.length; i++) {
314        oDiv = document.createElement("div");
315        oDiv.appendChild(document.createTextNode(aSuggestions[i]));
316        this.layer.appendChild(oDiv);
317    }
318    
319    this.layer.style.left = this.getLeft() + "px";
320	
321    this.layer.style.top = (this.getTop()+this.textbox.offsetHeight) + "px";
322    this.layer.style.visibility = "visible";
323
324};
325
326/**
327 * Inserts a suggestion into the textbox, highlighting the 
328 * suggested part of the text.
329 * @scope private
330 * @param sSuggestion The suggestion for the textbox.
331 */
332AutoSuggestControl.prototype.typeAhead = function (sSuggestion /*:String*/) {
333    //check for support of typeahead functionality
334    if (this.textbox.createTextRange || this.textbox.setSelectionRange){
335        var iLen = this.textbox.value.length; 
336        this.textbox.value = sSuggestion; 
337        this.selectRange(iLen, sSuggestion.length);
338    }
339};