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要小心谨慎在生产中使用这之前。
Web 动画 API
's
EffectTiming
dictionary's
iterationStart
property specifies the repetition number which repetition the animation begins at and its progress through it.
Element.animate()
,
KeyframeEffectReadOnly.KeyframeEffectReadOnly()
，和
KeyframeEffect.KeyframeEffect()
all accept an object of timing properties including
iterationStart.
值
iterationStart
corresponds directly to
AnimationEffectTimingReadOnly.iterationStart
in
timing
objects returned by
AnimationEffectReadOnly
,
KeyframeEffectReadOnly
，和
KeyframeEffect
.
var timingProperties = {
iterationStart = iterationNumber
};
timingProperties.iterationStart = iterationNumber;
A floating-point value whose value is at least 0 and is not
+Infinity
, indicating the offset into the number of iterations the animation sequence is to run at which to start animating.
iterationStart
represents the iteration index at which the animation effect begins as well as its progress through that iteration.
Usually you'll use a value between 0.0 and 1.0 to indicate an offset into the first run of the animation at which to begin the animation performance, but any positive, non-infinite value is allowed. Since all animations' iteration indexes start at 0, a value of 0.5 would start the animation halfway through its first iteration or loop. Meanwhile, a value of 1.2 means the animation will begin playback 20% of the way through its second iteration, and so forth.
It's currently undefined what happens if you specify a value of
iterationStart
which is greater than the value of
AnimationEffectTimingProperties.iterations
。见
issue 170 in the Web Animations API specification's issue tracker
for details and status of any changes to the specification in this regard.
| 规范 | 状态 | 注释 |
|---|---|---|
|
Web 动画
The definition of 'iterationStart' in that specification. |
工作草案 | 编者草案。 |
| 桌面 | 移动 | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
iterationStart
|
Chrome 52 | Edge ≤79 | Firefox 63 | IE No | Opera Yes | Safari No | WebView Android 52 | Chrome Android 52 | Firefox Android 63 | Opera Android No | Safari iOS No | Samsung Internet Android Yes |
完整支持
不支持
实验。期望将来行为有所改变。
Element.animate()
,
KeyframeEffectReadOnly()
，和
KeyframeEffect()
all accept an object of timing properties including this one.
AnimationEffectReadOnly.timing
,
KeyframeEffectReadOnly.timing
，和
KeyframeEffect.timing
).