This example walks you through the basics of creating a Slider from script. Both Sliders in this example link to text input fields that expect numeric input. The first Slider uses the default configuration, spanning values between 0 and 100, and is rendered inline.
The second Slider is configured to orient vertically (along the y axis) and the configuration includes minimum, maximium, and initial values. It is rendered into a </div>
.
The first Slider is set up in a more traditional JavaScript coding style and the second using the shorter, method chaining style.
Horizontal Slider
Vertical Slider
Horizontal Slider with default configuration
Sliders are horizontal by default, with available values ranging from 0 to 100, and an initial value of 0. The rail is 150 pixels long plus a few pixels for the rail's end caps.
var xSlider = new Y.Slider(); // render into the <span> next to the input xSlider.render( ".horiz_slider" );
Linking a Slider with a text input
To keep the Slider's value and input value in sync, you need to subscribe to events on both the input and the Slider. For Slider-to-input, the interesting event is valueChange
.
// Function to update the input value from the Slider value function updateInput( e ) { this.set( "value", e.newVal ); } var xInput = Y.one( "#horiz_value" ); // Subscribe to the Slider's valueChange event, passing the input as the 'this' xSlider.on( "valueChange", updateInput, xInput );
Linking the input with the Slider
To feed input changes back to the Slider we'll listen to its keyup
event. But we'll put the update on a delay to allow for a user to finish typing.
Additionally, we'll make the update function generic, since we have two Sliders in this example. We'll leverage the setData
and getData
methods of Node instances and store a reference to the Slider. Then we can use this object from inside the function to get back to the slider the input is related to.
// Function to pass input value back to the Slider function updateSlider( e ) { var data = this.getData(), slider = data.slider, value = parseInt( this.get( "value" ), 10 ); if ( data.wait ) { data.wait.cancel(); } // Update the Slider on a delay to allow time for typing data.wait = Y.later( 200, slider, function () { data.wait = null; this.set( "value", value ); } ); } xInput.setData( { slider: xSlider } ); xInput.on( "keyup", updateSlider );
Creating the vertical Slider
To create a vertical Slider you just need to set the axis
attribute to "y".
For this Slider, we'll use more extensive method chaining and include value and rail configurations. First we'll change the value range from 0 - 100 to -100 - +100 and set an initial value of +30.
Note that the min
configuration is 100 in this case because the top is associated with the minimum value. Slider has no qualms about min
being greater than max
.
The rail length is then configured to be 201 pixels, so each value has a distinct pixel position on the rail (don't forget 0).
Finally, the valueChange
subscription is included in the configuration as well.
var yInput = Y.one( "#vert_value" ); yInput.setData( "slider", new Y.Slider({ axis: 'y', min : 100, // min is the value at the top max : -100, // max is the value at the bottom value : 30, // initial value length: '201px', // rail extended to afford all values // construction-time event subscription after : { valueChange: Y.bind( updateInput, yInput ) } }).render( ".vert_slider" ) // render returns the Slider ) // set( "data", ... ) returns the Node .on( "keyup", updateSlider ); // chain the keyup subscription
Full Code Listing
HTML
Note: be sure to add the yui3-skin-sam
classname to the
page's <body>
element or to a parent element of the widget in order to apply
the default CSS skin. See Understanding Skinning.
<div id="demo" class="example yui3-skin-sam"> <!-- You need this skin class --> <h4>Horizontal Slider</h4> <p> <label for="horiz_value">Value: </label> <input id="horiz_value" value="0"> <span class="horiz_slider"></span> </p> <h4>Vertical Slider</h4> <p><label for="vert_value">Value: </label><input id="vert_value" value="30"></p> <div class="vert_slider"></div> </div>
JavaScript
// Create a YUI instance and request the slider module and its dependencies YUI().use("slider", function (Y) { var xInput, // input tied to xSlider yInput, // input tied to ySlider xSlider; // horizontal Slider // Function to pass input value back to the Slider function updateSlider( e ) { var data = this.getData(), slider = data.slider, value = parseInt( this.get( "value" ), 10 ); if ( data.wait ) { data.wait.cancel(); } // Update the Slider on a delay to allow time for typing data.wait = Y.later( 200, slider, function () { data.wait = null; this.set( "value", value ); } ); } // Function to update the input value from the Slider value function updateInput( e ) { this.set( "value", e.newVal ); } // Create a horizontal Slider using all defaults xSlider = new Y.Slider(); // Link the input value to the Slider xInput = Y.one( "#horiz_value" ); xInput.setData( { slider: xSlider } ); // Pass the input as the 'this' object inside updateInput xSlider.after( "valueChange", updateInput, xInput ); xInput.on( "keyup", updateSlider ); // Render the Slider next to the input xSlider.render('.horiz_slider') // Create the vertical Slider. yInput = Y.one( "#vert_value" ); yInput.setData( "slider", new Y.Slider({ axis: 'y', min : 100, // min is the value at the top max : -100, // max is the value at the bottom value : 30, // initial value length: '201px', // rail extended to afford all values // construction-time event subscription after : { valueChange: Y.bind( updateInput, yInput ) } }).render( ".vert_slider" ) // render returns the Slider ) // set( "data", ... ) returns the Node .on( "keyup", updateSlider ); // chain the keyup subscription });