Angular 2 Datalist Option click event in Angular 2 [duplicate] - html

Question

I'm using a <datalist>
<datalist id="items"></datalist>
And using AJAX to populate the list
function callServer (input) {
xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function(){
if (xmlhttp.readyState == 4 && xmlhttp.status == 200){
//return the JSON object
console.log(xmlhttp.responseText);
var arr = JSON.parse(xmlhttp.responseText);
var parentDiv = document.getElementById('items');
parentDiv.innerHTML = "";
//fill the options in the document
for(var x = 0; x < arr.length; x++) {
var option = document.createElement('option');
option.value = arr[x][0];
option.innerHTML = arr[x][1];
//add each autocomplete option to the 'list'
option.addEventListener("click", function() {
console.log("Test");
});
parentDiv.appendChild(option);
};
}
}
xmlhttp.open("GET", "incl/search.php?value="+input.value, true);
xmlhttp.send();
}
However I can't get it to perform an action when I click on a selection in the datalist, for example if I type in "Ref F" and the item "Ref flowers" comes up, if I click on it I need to execute an event.
How can I do this?
option.addEventListener("click", function() {
option.addEventListener("onclick", function() {
option.addEventListener("change", function() {

Answer 1

Sorry for digging up this question, but I've had a similar problem and have a solution, that should work for you, too.
function onInput() {
var val = document.getElementById("input").value;
var opts = document.getElementById('dlist').childNodes;
for (var i = 0; i < opts.length; i++) {
if (opts[i].value === val) {
// An item was selected from the list!
// yourCallbackHere()
alert(opts[i].value);
break;
}
}
}
<input type='text' oninput='onInput()' id='input' list='dlist' />
<datalist id='dlist'>
<option value='Value1'>Text1</option>
<option value='Value2'>Text2</option>
</datalist>
This solution is derived from Stephan Mullers solution. It should work with a dynamically populated datalist as well.
Unfortunaltely there is no way to tell whether the user clicked on an item from the datalist or selected it by pressing the tab-key or typed the whole string by hand.

Answer 2

Due to the lack of events available for <datalist> elements, there is no way to a selection from the suggestions other than watching the input's events (change, input, etc). Also see my answer here: Determine if an element was selected from HTML 5 datalist by pressing enter key
To check if a selection was picked from the list, you should compare each change to the available options. This means the event will also fire when a user enters an exact value manually, there is no way to stop this.
document.querySelector('input[list="items"]').addEventListener('input', onInput);
function onInput(e) {
var input = e.target,
val = input.value;
list = input.getAttribute('list'),
options = document.getElementById(list).childNodes;
for(var i = 0; i < options.length; i++) {
if(options[i].innerText === val) {
// An item was selected from the list!
// yourCallbackHere()
alert('item selected: ' + val);
break;
}
}
}
<input list="items" type="text" />
<datalist id="items">
<option>item 1</option>
<option>item 2</option>
</datalist>

Answer 3

Use keydown
Contrary to the other answers, it is possible to detect whether an option was typed or selected from the list.
Both typing and <datalist> clicks trigger the input's keydown listener, but only keyboard events have a key property. So if a keydown is triggered having no key property, you know it was a click from the list
Demo:
const opts = document.getElementById('dlist').childNodes;
const dinput = document.getElementById('dinput');
let eventSource = null;
let value = '';
dinput.addEventListener('keydown', (e) => {
eventSource = e.key ? 'input' : 'list';
});
dinput.addEventListener('input', (e) => {
value = e.target.value;
if (eventSource === 'list') {
alert('CLICKED! ' + value);
}
});
<input type="text" id="dinput" list="dlist" />
<datalist id="dlist">
<option value="Value1">Text1</option>
<option value="Value2">Text2</option>
</datalist>
Notice it doesn't alert if the value being clicked is already in the box, but that's probably desirable. (This could also be added by using an extra tracking variable that will be toggled in the keydown listener.)

Answer 4

Datalist actually don't have an event (not all browsers), but you can detect if a datalist option is selected in this way:
<input type="text" list="datalist" />
<datalist id="datalist">
<option value="item 1" />
<option value="item 2" />
</datalist>
window.addEventListener('input', function (e) {
let event = e.inputType ? 'input' : 'option selected'
console.log(event);
}, false);
demo

Answer 5

Shob's answer is the only one which can detect when an option gets clicked as well as not trigger if an intermediary written text matches an option (e.g.: if someone types "Text1" to see the options "Text11", "Text12", etc. it would not trigger even if "Text1" is inside the datalist).
The original answer however did not seem to work on newer versions of Firefox as the keydown event does not trigger on clicks so I adapted it.
let keypress = false;
document.getElementById("dinput").addEventListener("keydown", (e) => {
if(e.key) {
keypress = true;
}
});
document.getElementById("dinput").addEventListener('input', (e) => {
let value = e.target.value;
if (keypress === false) {
// Clicked on option!
console.debug("Value: " + value);
}
keypress = false;
});
<input type="text" id="dinput" list="dlist" />
<datalist id="dlist">
<option value="Value1">Text1</option>
<option value="Value2">Text2</option>
</datalist>

Answer 6

Datalist don't support click listener and OnInput is very costly, checking everytime all the list if anything change.
What I did was using:
document.querySelector('#inputName').addEventListener("focusout", onInput);
FocusOut will be triggered everytime a client click the input text and than click anywhere else. If they clicked the text, than clicked somewhere else I assume they put the value they wanted.
To check if the value is valid you do the same as the input:
function onInput(e) {
var val = document.querySelector('#inputName').value;
options = document.getElementById('datalist').childNodes;
for(var i = 0; i < options.length; i++) {
if(options[i].innerText === val) {
console.log(val);
break;
}
}
}

Answer 7

<input type="text" id="buscar" list="lalista"/>
<datalist id="lalista">
<option value="valor1">texto1</option>
<option value="valor2">texto2</option>
<option value="valor3">texto3</option>
</datalist>
//0 if event raised from datalist; 1 from keyboard
let idTimeFuekey = 0;
buscar.oninput = function(){
if(buscar.value && idTimeFuekey==0) {
alert('Chévere! vino desde la lista')
}
};
buscar.onkeydown = function(event){
if(event.key){ //<-- for modern & non IE browser, more direct solution
window.clearInterval(idTimeFuekey);
idTimeFuekey = window.setInterval(function(){ //onkeydown --> idTimeFuekey++ (non 0)
window.clearInterval(idTimeFuekey);
idTimeFuekey = 0 //after 500ms onkeydown --> 0 (could work 500, 50, .. 1)
}, 500)
}
}

Answer 8

Well, at least in Firefox the onselect event works on the input tag
<input type="text" id="dinput" list="dlist" onselect="alert(this.value)"/>
<datalist id="dlist">
<option value="Value1">Text1</option>
<option value="Value2">Text2</option>
</datalist>

Answer 9

After having this problem and not finding a suitable solution, I gave it a shot.
What I did was look at the "inputType" of the given input event on top of the event toggle variable from above, like so:
eventSource = false;
const selector = document.getElementById("yourElementID");
selector.addEventListener('input', function(evt) {
if(!eventSource) {
if(evt.inputType === "insertReplacementText") {
console.log(selector.value);
}
}
});
selector.addEventListener('keydown', function(evt) {
eventSource = !evt.key;
});
This works if you want to allow the user to search a field but only hit a specific function/event on selection from the datalist itself. Hope it helps!
Edit: Forgot to mention this was done through Firefox and has not been tested on other browsers.