friendica/view/theme/frio/templates/theme_settings.tpl

<link rel="stylesheet" href="{{$baseurl}}/view/theme/frio/frameworks/jRange/jquery.range.css" type="text/css" media="screen" />
<script src="{{$baseurl}}/view/theme/quattro/jquery.tools.min.js"></script>
<script src="{{$baseurl}}/view/theme/frio/frameworks/jRange/jquery.range.js"></script>
<script type="text/javascript" src="{{$baseurl}}/view/js/ajaxupload.js" ></script>

{{include file="field_select.tpl" field=$scheme}}

{{if $nav_bg}}{{include file="field_input.tpl" field=$share_string}}{{/if}}
{{if $nav_bg}}{{include file="field_colorinput.tpl" field=$nav_bg}}{{/if}}
{{if $nav_icon_color}}{{include file="field_colorinput.tpl" field=$nav_icon_color}}{{/if}}
{{if $link_color}}{{include file="field_colorinput.tpl" field=$link_color}}{{/if}}

{{if $background_color}}{{include file="field_colorinput.tpl" field=$background_color}}{{/if}}

{{* The slider for the content opacity - We use no template for this since it is only used at this page *}}
{{if $contentbg_transp}}
<div class="form-group field input color">
	<label for="id_{{$contentbg_transp.0}}" id="label_{{$contentbg_transp.0}}">{{$contentbg_transp.1}}</label>
	<input type="hidden" class="form-control color slider-input" name="{{$contentbg_transp.0}}" id="{{$contentbg_transp.0}}" type="text" value="{{$contentbg_transp.2}}" aria-describedby="{{$contentbg_transp.0}}_tip">
	<span id="{{$contentbg_transp.0}}_tip" class="help-block" role="tooltip">{{$contentbg_transp.3}}</span>
	<div id="end_{{$contentbg_transp.0}}" class="field_end"></div>
</div>
{{/if}}

{{if $background_image}}{{include file="field_fileinput.tpl" field=$background_image}}{{/if}}

<div id="frio_bg_image_options" style="display: none;">
	<label>{{$bg_image_options_title}}:</label>
{{foreach $bg_image_options as $options}}
	{{include file="field_radio.tpl" field=$options}}
{{/foreach}}
</div>

{{if $login_bg_image}}{{include file="field_fileinput.tpl" field=$login_bg_image}}{{/if}}
{{if $login_bg_color}}{{include file="field_colorinput.tpl" field=$login_bg_color}}{{/if}}

<script type="text/javascript">
	$(document).ready(function() {

		function GenerateShareString() {
			var theme = {};
			// Parse initial share_string
			if ($("#id_frio_nav_bg").length) {
				theme.nav_bg = $("#id_frio_nav_bg").val();
			}

			if ($("#id_frio_nav_icon_color").length) {
				theme.nav_icon_color = $("#id_frio_nav_icon_color").val();
			}

			if ($("#id_frio_link_color").length) {
				theme.link_color = $("#id_frio_link_color").val();
			}

			if ($("#id_frio_background_color").length) {
				theme.background_color = $("#id_frio_background_color").val();
			}

			if ($("#id_frio_background_image").length) {
				theme.background_image = $("#id_frio_background_image").val();

				if (theme.background_image.length > 0) {
					if ($("#id_frio_bg_image_option_stretch").is(":checked") == true) {
						theme.background_image_option = "stretch";
					}
					if ($("#id_frio_bg_image_option_cover").is(":checked") == true) {
						theme.background_image_option = "cover";
					}
					if ($("#id_frio_bg_image_option_contain").is(":checked") == true) {
						theme.background_image_option = "contain";
					}
					if ($("#id_frio_bg_image_option_repeat").is(":checked") == true) {
						theme.background_image_option = "repeat";
					}
				 }
			}

			if ($("#frio_contentbg_transp").length) {
				theme.contentbg_transp = $("#frio_contentbg_transp").val();
			}

			if ($("#id_frio_login_bg_image").length) {
				theme.login_bg_image = $("#id_frio_login_bg_image").val();
			}

			if ($("#id_frio_login_bg_color").length) {
				theme.login_bg_color = $("#id_frio_login_bg_color").val();
			}
			if (!($("#id_frio_share_string").is(":focus"))){
				var share_string = JSON.stringify(theme);
				$("#id_frio_share_string").val(share_string);
			}
		}

		// interval because jquery.val does not trigger events
		window.setInterval(GenerateShareString, 500);
		GenerateShareString();

		// Take advantage of the effects of previous comment
		$(document).on("keyup", "#id_frio_share_string", function() {
			theme = JSON.parse($("#id_frio_share_string").val());

			if ($("#id_frio_nav_bg").length) {
				$("#id_frio_nav_bg").val(theme.nav_bg);
			}

			if ($("#id_frio_nav_icon_color").length) {
				$("#id_frio_nav_icon_color").val(theme.nav_icon_color);
			}

			if ($("#id_frio_link_color").length) {
				 $("#id_frio_link_color").val(theme.link_color);
			}

			if ($("#id_frio_background_color").length) {
				$("#id_frio_background_color").val(theme.background_color);
			}

			if ($("#id_frio_background_image").length) {
				$("#id_frio_background_image").val(theme.background_image);
				var elText = theme.background_image;
				if(elText.length !== 0) {
					$("#frio_bg_image_options").show();
				} else {
					$("#frio_bg_image_options").hide();
				}

				switch (theme.background_image_option) {
					case 'stretch':
						$("#id_frio_bg_image_option_stretch").prop("checked", true);
						break;
					case 'cover':
						$("#id_frio_bg_image_option_cover").prop("checked", true);
						break;
					case 'contain':
						$("#id_frio_bg_image_option_contain").prop("checked", true);
						break;
					case 'repeat':
						$("#id_frio_bg_image_option_repeat").prop("checked", true);
						break;
				}
			}

			if ($("#frio_contentbg_transp").length) {
				$("#frio_contentbg_transp").val(theme.contentbg_transp);
			}

			if ($("#id_frio_login_bg_image").length) {
				$("#id_frio_login_bg_image").val(theme.login_bg_image);
			}

			if ($("#id_frio_login_bg_color").length) {
				$("#id_frio_login_bg_color").val(theme.login_bg_color);
			}
		});
		// Create colorpickers
		$("#frio_nav_bg, #frio_nav_icon_color, #frio_background_color, #frio_link_color, #frio_login_bg_color").colorpicker({format: 'hex', align: 'left'});

		// show image options when user user starts to type the address of the image
		$("#id_frio_background_image").keyup(function(){
			var elText = $(this).val();
			if(elText.length !== 0) {
				$("#frio_bg_image_options").show();
			} else {
				$("#frio_bg_image_options").hide();
			}
		});

		// show the image options is there is allready an image
		if($("#id_frio_background_image").val().length != 0) {
				$("#frio_bg_image_options").show();
		}

		$('.slider-input').jRange({
			from: 0,
			to: 100,
			step: 1,
			scale: [0,10,20,30,40,50,60,70,80,90,100],
			format: '%s',
			width: '100%',
			showLabels: true,
			theme: 'theme-frio',
		});

		// The position of the slider is wrong calculated on hidden elements.
		// So set an event listener toggle and update the jRange value.
		$(document).on('click', '#custom-settings-title a', function() {
			var bgTransp = $('#frio_contentbg_transp').val();
			$('.slider-input').jRange('setValue', bgTransp);
		});

	});
</script>

<div class="settings-submit-wrapper form-group pull-right">
	<button type="submit" value="{{$submit}}" class="settings-submit btn btn-primary" name="frio-settings-submit">{{$submit}}</button>
</div>
<div class="clearfix"></div>

<script type="text/javascript">
	$(".inputRange").rangeinput();
</script>