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# YUI Library Examples: Slider Control: Dual-thumb Slider with range highlight

# Slider Control: Dual-thumb Slider with range highlight

This example demonstrates a horizontal dual-thumb Slider with custom code to add a highlight to the bounded range. Some characteristics to note include the following:

- The thumbs are set on a slide bar with a 300 pixel range.
- The thumbs are configured with a 12 pixel tick size.
- Clicking on the background will animate the nearest thumb.

View example in new window.

Range offsets: 0 - 300

Status: ok

## Adding a range highlight to a dual thumb Slider

DualSlider does not come prebuilt with support for a range highlight. This example demonstrates how to add this functionality to a DualSlider.

You supply your own markup for the slider. Keep in mind the following points about markup for YUI Dual Thumb Slider Control implementations:

- The thumb elements should be children of the slider background.
- We use `<img>` elements rather than a CSS background for the thumbs to get around a performance bottleneck when animating thumb positions in IE.
- Don't apply a CSS border to the slider background.
- The background element should have an explicit CSS position: `relative` or `absolute`.
- Both thumb elements should have an explicit CSS position: `absolute` and be initially placed at the zero position of the background. Set their initial position in the constructor if desired.

## CSS:

The example will use the css sprites technique to change the color of the highlight based on assigned classes.

#demo_bg { position: relative; background: url(../slider/assets/dual_thumb_bg.gif) 0 5px no-repeat; height: 28px; width: 310px; } #demo_bg div { position: absolute; cursor: default; top: 4px; } /* Here's the highlight element */ #demo_bg span { position: absolute; background: url(../slider/assets/dual_thumb_highlight.gif) 0 0 repeat-x; top: 10px; left: 12px; height: 13px; width: 288px; } #demo_bg .caution { background-position: 0 -13px; } #demo_bg .boom, #demo_bg .danger { background-position: 0 -26px; } /* We'll use the same class names for the status report region */ p .ok { color: #3a3; font-weight: bold; text-transform: uppercase; } p .caution { background: #ff3; color: #770; font-weight: bold; font-style: italic; padding: 0 1ex; text-transform: uppercase; } p .danger { color: #f33; font-weight: bold; text-decoration: blink; text-transform: uppercase; } p .boom { color: #fff; background: #000; padding: 0 1ex; }

## Markup:

Here we add an additional `span` element to use as our highlight.

<div id="demo_bg" title="Range slider"> <span id="demo_highlight"></span> <div id="demo_min_thumb"><img src="assets/l-thumb-round.gif"></div> <div id="demo_max_thumb"><img src="assets/r-thumb-round.gif"></div> </div> <p>Thumb values: <span id="demo_range"></span></p> <p>Status: <span id="demo_value"></span></p>

## Code:

(function () { YAHOO.namespace('example'); var Dom = YAHOO.util.Dom; // Slider has a range of 300 pixels var range = 300; // Set up 12 pixel ticks var tickSize = 12; // Some arbitrary ranges to cue status changes var caution_range = 150, danger_range = 75, boom_range = 13; YAHOO.util.Event.onDOMReady(function () { var reportSpan = Dom.get("demo_range"); var calculatedSpan = Dom.get("demo_value"); // Create the DualSlider var slider = YAHOO.widget.Slider.getHorizDualSlider("demo_bg", "demo_min_thumb", "demo_max_thumb", range, tickSize); // Decorate the DualSlider instance with some new properties and // methods to maintain the highlight element YAHOO.lang.augmentObject(slider, { // The current status _status : 'ok', // The highlight element _highlight : Dom.get("demo_highlight"), // A simple getter method for the status getStatus : function () { return this._status; }, // A method to update the status and update the highlight updateHighlight : function () { var delta = this.maxVal - this.minVal, newStatus = 'ok'; if (delta < boom_range) { newStatus = 'boom'; } else if (delta < danger_range) { newStatus = 'danger'; } else if (delta < caution_range) { newStatus = 'caution'; } if (this._status !== newStatus) { // Update the highlight class if status is changed Dom.replaceClass(this._highlight,this._status,newStatus); this._status = newStatus; } if (this.activeSlider === this.minSlider) { // If the min thumb moved, move the highlight's left edge Dom.setStyle(this._highlight,'left', (this.minVal + 12) + 'px'); } // Adjust the width of the highlight to match inner boundary Dom.setStyle(this._highlight,'width', Math.max(delta - 12,0) + 'px'); } },true); // Attach the highlight method to the slider's change event slider.subscribe('change',slider.updateHighlight,slider,true); // Create an event callback to update some display fields var report = function () { reportSpan.innerHTML = slider.minVal + ' - ' + slider.maxVal; // Call our conversion function calculatedSpan.innerHTML = calculatedSpan.className = slider.getStatus(); }; // Subscribe to the slider's change event to report the status. slider.subscribe('change',report); // Attach the slider to the YAHOO.example namespace for public probing YAHOO.example.slider = slider; }); })();

### YUI Logger Output:

Note: Logging and debugging is currently turned off for this example.

Reload with logging
and debugging enabled.

### Slider Control Examples:

- Basic Vertical Slider
- Horizontal Slider with Tick Marks
- RBG Slider Control
- Bottom to top Vertical Slider
- Horizontal Slider with two thumbs
- Dual-thumb Slider with range highlight
- Slider Button (included with examples for Button Control)
- Complex Application (included with examples for Layout Manager (beta))

### More Slider Control Resources:

- User's Guide (external)
- API Documentation
- Cheat Sheet PDF (external)

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