Component Methods

• this.$element('id').animate(Object, Object)

After a component is assigned the id attribute, you can use the ID to obtain the component objects and call functions.

this.$element('id').animate(Object, Object)

You can use the animate(keyframes, options) method to obtain an animation object. This object supports properties, methods, and events of the animation component. If animate is called for multiple times and the replace policy is used, parameters passed to the last call will take effect.

• keyframes

  Parameter	Type	Description
  frames	Array<Style>	Array of objects used to set animation style attributes. For details about style attributes, see Style attributes.

  Table 1 Style attributes

  Parameter	Type	Default Value	Description
  width	number	-	Width set for the component during playback of the animation.
  height	number	-	Height set for the component during playback of the animation.
  backgroundColor	<color>	none	Background color set for the component during playback of the animation.
  opacity	number	1	Opacity set for the component. The value ranges from 0 to 1.
  backgroundPosition	string	-	The value format is x y, in percentage or pixels. The first value indicates the horizontal position, and the second value indicates the vertical position. If only one value is specified, the other value is 50% by default.
  transformOrigin	string	'center center'	Origin position of the transformed element. The first value indicates the x-axis position. The value can be left, center, right, a length, or a percentage. The second value indicates the y-axis position. The value can be top, center, bottom, a length, or a percentage.
  transform	Transform	-	Transformation type set for a transformed element.
  offset	number	-	The value of offset must be within (0.0,1.0] and sorted in ascending order if it is provided. If there are only two frames, offset can be left empty. If there are more than two frames, offset is mandatory.

• options attributes

  Parameter	Type	Default Value	Description
  duration	number	0	Duration for playing the animation, in milliseconds.
  easing	string	linear	Time curve of the animation. For details about the supported types, see Available values of the easing attribute.
  delay	number	0	Delay for the animation start. The default value indicates no delay.
  iterations	number | string	1	Number of times the animation will be played. number indicates a fixed number of playback operations, and Infinity indicates an unlimited number of playback operations.
  fill	string	none	Start and end styles of the animation none: No style is applied to the target before or after the animation is executed. forwards: The target keeps the state at the end of the animation (defined in the last key frame) after the animation is executed.

  Table 2 Available values of the easing attribute

  Type	Description
  linear	The animation speed keeps unchanged.
  ease-in	The animation starts at a low speed. cubic-bezier(0.42, 0.0, 1.0, 1.0).
  ease-out	The animation ends at a low speed. cubic-bezier(0.0, 0.0, 0.58, 1.0).
  ease-in-out	The animation starts and ends at a low speed. cubic-bezier(0.42, 0.0, 0.58, 1.0).
  friction	Damping curve, cubic-bezier(0.2, 0.0, 0.2, 1.0).
  extreme-deceleration	Extreme deceleration curve, cubic-bezier(0.0, 0.0, 0.0, 1.0).
  sharp	Sharp curve, cubic-bezier(0.33, 0.0, 0.67, 1.0).
  rhythm	Rhythm curve, cubic-bezier(0.7, 0.0, 0.2, 1.0).
  smooth	Smooth curve, cubic-bezier(0.4, 0.0, 0.4, 1.0).
  cubic-bezier(x1, y1, x2, y2)	You can customize an animation speed curve in the cubic-bezier() function. The x and y values of each input parameter must be between 0 and 1.
  steps(number, step-position)	Step curve. The number must be set and only an integer is supported. step-position is optional. It can be set to start or end. The default value is end.

• Return value

  Attributes supported by the animation object

  Attribute	Type	Description
  finished	boolean	Read-only attribute, which indicates whether the animation playback is complete.
  pending	boolean	Read-only attribute, which indicates whether the animation is waiting for the completion of other asynchronous operations (for example, start an animation with a delay).
  playState	string	Read-write attribute, which indicates the playback status of the animation: idle: The animation is not running (playback ended or not started). running: The animation is running. paused: The animation is paused. finished: Animation playback ends.
  startTime	number	Read-write attribute, which indicates the animation start time. This attribute is similar to delay in the options attribute.

  Methods supported by the animation object

  Method	Parameter	Description
  play	-	Plays the animation.
  finish	-	Ends the animation.
  pause	-	Pauses the animation.
  cancel	-	Cancels the animation.
  reverse	-	Plays the animation in reverse.

  Events supported by the animation object

  Event	Description
  cancel	The animation is forcibly canceled.
  finish	The animation playback is complete.
  repeat	The animation repeats.

• Example code:

  // xxx.js
  import prompt from '@system.prompt';
  export default {
    data : {
      animation:'',
    },
    onInit() {
    },
    onShow() {
      var options = {
        duration: 1500,
        easing: 'friction',
        delay: 500,
        fill: 'forwards',
        iterations: 2,
      };
      var frames = [
        {transform: {translate: '-120px -0px'}, opacity: 0.1, offset: 0.0},
        {transform: {translate: '120px 0px'}, opacity: 1.0, offset: 1.0}
      ];
      this.animation = this.$element('idName').animate(frames, options);
      // handle finish event
      this.animation.onfinish = function() {
        prompt.showToast({
          message: "The animation is finished."
        });
      };
      // handle cancel event
      this.animation.oncancel = function() {
        prompt.showToast({
          message: "The animation is canceled."
        });
      };
      // handle repeat event
      this.animation.onrepeat = function() {
        prompt.showToast({
          message: "The animation is repeated."
        });
      };
    },
    start() {
      this.animation.play();
    },
    cancel() {
      this.animation.cancel();
    }
  }