Replace single questions dropdown by plugin

Description

When viewing in both Single and Single grid dropdown layout. There are 3 problems because using the default select dropdown tag:
• Some characters on keyboard decode/encode problem. Such as: Ampersand ( & ), single quotation  ( ' ), double quotation marks ( " ), is more than ( > ), is less than ( < ).
• Same problem with characters not on keyboard. For example: ÷, ×, ±, ≠, ≡, ≤, ≥, …, ‘, °C and maybe more than that.
• Problem with display HTML format in dropdown list when using it to design UI.

Expectation

These decode/encode problems will be fix and display normally like other question type and layout.

Example

Before:

After: File:After-replace.PNG

Solution

Replace select dropdown default by using plugin 'select2'.
URL: https://select2.org/

Code

Add this code to Javascript editor in single or single grid dropdown layout.

Question.bind('afterShowQuestion', function(ev, question, $el) {
	$.when(
		$.fn.select2 || $.ajax({
			type: 'GET',
			dataType: 'script',
			cache: true,
			url: 'https://cdn.catglobe.com/select2-4.1.0/js/select2.min.js'
		}),
		$.fn.select2 || $('<link/>', {rel: 'stylesheet', href: 'https://cdn.catglobe.com/select2-4.1.0/css/select2.min.css'}).appendTo('head')
	).done(function() {
		$('select', $el).select2({
			minimumResultsForSearch: Infinity,
			width: '100%',
			templateResult: function(state) {
				//custom option template in dropdown
				if (!$(state.element).instance()) return null;
				return $('<div/>').html(state.text).css({'text-align': 'left'});
			},
			templateSelection: function(state) {
				//custom selected value
				if (!$(state.element).instance()) return question.selectText;
				return $('<div/>').html(state.text).css({'text-align': 'left'});
			}
		});
		$('.select2-selection', $el).css({height: 'auto', 'min-height': '28px'});
	});
});