KeyframeEffect.setKeyframes()

The setKeyframes() method of the KeyframeEffect interface replaces the keyframes that make up the affected KeyframeEffect with a new set of keyframes.

Syntax

existingKeyframeEffect.setKeyframes(keyframes);

Parameters

keyframes

A keyframe object or null. If set to null, the keyframes are replaced with a sequence of empty keyframes.

There are two different ways to format keyframes:

1. An object containing key-value pairs consisting of the property to animate and an array of values to iterate over.

   element.animate({
     opacity: [ 0, 1 ],          // [ from, to ]
     color:   [ "#fff", "#000" ] // [ from, to ]
   }, 2000);
   

2. An array of objects (keyframes) consisting of properties and values to iterate over. This is the canonical format returned by the getKeyframes() method.

   element.animate([ 
     { // from
       opacity: 0,
       color: "#fff"
     }, 
     { // to
       opacity: 1,
    ​   color: "#000"
     }
   ], 2000);

   With this latter form it is also possible to specify offsets for each keyframe by providing an offset value.

   element.animate([ { opacity: 1 },
                     { opacity: 0.1, offset: 0.7 },
                     { opacity: 0 } ],
                   2000);
   

   Note: offset values, if provided, must be between 0.0 and 1.0 and arranged in ascending order.

   Furthermore, using this form it is also possible to specify easing to apply between keyframes by providing an easing value as illustrated below.

   element.animate([ { opacity: 1, easing: 'ease-out' },
                     { opacity: 0.1, easing: 'ease-in' },
                     { opacity: 0 } ],
                   2000);
   

   In this example, the specified easing only applies from the keyframe where it is specified until the next keyframe. Any easing value specified on the options argument, however, applies across a single iteration of the animation — for the entire duration.

 

Attributes

You can specify as many property value pairs as are contained in each keyframe of the animation. Each property value pairs support the standard CSS properties, but also the following additional attributes:

offset

The offset of the keyframe specified as a number between 0.0 and 1.0 inclusive or null. This is equivalent to specifying start and end states in percentages in CSS stylesheets using @keyframes. This will be null if the keyframe is automatically spaced using KeyframeEffect.spacing.

computedOffset

The computed offset for this keyframe, calculated when the list of computed keyframes was produced according to KeyframeEffect.spacing. Unlike offset, above, the computedOffset is never null.

easing

The timing function used from this keyframe until the next keyframe in the series.

composite

The KeyframeEffectReadOnly.composite operation used to combine the values specified in this keyframe with the underlying value. This will be absent if the composite operation specified on the effect is being used.

 

 

Return value

Void.

Exceptions

Examples

// passing an array of keyframe objects
existingKeyframeEffect.setKeyframes(
[
  { color: 'blue' },
    { color: 'green', left: '10px' }
  ]
);

// passing an object with arrays for values
existingKeyframeEffect.setKeyframes(
  {
    color: ['blue', 'green'],
    left: [ '0', '10px']
  }
);

// passing a single-member object
existingKeyframeEffect.setKeyframes(
  {
    color: 'blue'
  }
);

Specifications

Browser compatibility

See also

• KeyframeEffect Interface
• Web Animations API