iSharkFly-Docs
/
angular-docs-cn
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

docs(animations): update copy (#2379) 

* docs(animations): update copy
This commit is contained in:
Kapunahele Wong 2016-09-20 17:31:48 -04:00 committed by Kathy Walrath
parent 55bf126489
commit 7252bd1553
1 changed files with 107 additions and 115 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

222
public/docs/ts/latest/guide/animations.jade
View File

@ -1,138 +1,132 @@
include ../_util-fns
:marked
Motion is an important aspect in the design of modern web applications. We want our
user interfaces to have smooth transitions between states, and engaging animations
Motion is an important aspect in the design of modern web applications. Good
user interfaces transition smoothly between states with engaging animations
that call attention where it's needed. Well-designed animations can make a UI not only
more fun but also easier to use.
Angular's animation system gives us what we need to make the kinds of animations we want.
We can build animations that run with the same kind of native performance that we're used
to with pure CSS animations. But we can also have our animation logic tightly integrated
with the rest of our application code, where they can be easily triggered and controlled.
Angular's animation system lets you build animations that run with the same kind of native
performance found in pure CSS animations. You can also tightly integrate your
animation logic with the rest of your application code, for ease of control.
.alert.is-helpful
:marked
Angular animations are built on top of the standard [Web Animations API](https://w3c.github.io/web-animations/)
and they run natively on [browsers that support it](http://caniuse.com/#feat=web-animation).
and run natively on [browsers that support it](http://caniuse.com/#feat=web-animation).
For other browsers, a polyfill is required. Grab
[`web-animations.min.js` from here](https://github.com/web-animations/web-animations-js) and
[`web-animations.min.js` from GitHub](https://github.com/web-animations/web-animations-js) and
add it to your page.
A more lightweight polyfill maintained by the Angular team is coming soon.
:marked
# Table of Contents
# Contents
* [Quickstart Example: Transitioning Between Two States](#example-transitioning-between-states)
* [States and Transitions](#states-and-transitions)
* [Example: Entering and Leaving](#example-entering-and-leaving)
* [Example: Entering and Leaving from Different States](#example-entering-and-leaving-from-different-states)
* [Animatable Properties and Units](#animatable-properties-and-units)
* [Automatic Property Calculation](#automatic-property-calculation)
* [Animation Timing](#animation-timing)
* [Multi-Step Animations with Keyframes](#multi-step-animations-with-keyframes)
* [Parallel Animation Groups](#parallel-animation-groups)
* [Animation callbacks](#animation-callbacks)
* [Example: Transitioning between two states](#example-transitioning-between-states).
* [States and transitions](#states-and-transitions).
* [Example: Entering and leaving](#example-entering-and-leaving).
* [Example: Entering and leaving from different states](#example-entering-and-leaving-from-different-states).
* [Animatable properties and units](#animatable-properties-and-units).
* [Automatic property calculation](#automatic-property-calculation).
* [Animation timing](#animation-timing).
* [Multi-step animations with keyframes](#multi-step-animations-with-keyframes).
* [Parallel animation groups](#parallel-animation-groups).
* [Animation callbacks](#animation-callbacks).
.l-sub-section
:marked
The examples referenced in this chapter are available as a <live-example></live-example>.
The examples in this page are available as a <live-example></live-example>.
a(id="example-transitioning-between-states")
.l-main-section
:marked
## Quickstart Example: Transitioning Between Two States
## Quickstart example: Transitioning between two states
figure
img(src="/resources/images/devguide/animations/animation_basic_click.gif" alt="A simple transition animation" align="right" style="width:220px;margin-left:20px" )
:marked
Let's build a simple animation that transitions an element between two states
You can build a simple animation that transitions an element between two states
driven by a model attribute.
Animations are defined inside `@Component` metadata. Before we can add some, we need
Animations are defined inside `@Component` metadata. Before you can add animations, you need
to import a few animation-specific functions:
+makeExample('animations/ts/app/hero-list-basic.component.ts', 'imports')(format=".")
:marked
With these we can now define an *animation trigger* called `heroState` in the component
metadata. It has animated transitions between two states: `active` and `inactive`. When a
hero is active, we display the element in a slightly larger size and lighter color.
With these, you can define an *animation trigger* called `heroState` in the component
metadata. It uses animations to transition between two states: `active` and `inactive`. When a
hero is active, the element appears in a slightly larger size and lighter color.
+makeExample('animations/ts/app/hero-list-basic.component.ts', 'animationdef')(format=".")
.alert.is-helpful
:marked
In this example we are defining animation styles (color and transform) inline in the
animation metadata. In an upcoming release of Angular, support will be added for pulling
the styles in from the component CSS stylesheet instead.
In this example, you are defining animation styles (color and transform) inline in the
animation metadata.
:marked
We now have an animation defined but it is not yet used anywhere. We can change that by
attaching it to one or more elements in the component's template using the "`[@triggerName]`"
syntax:
Now, using the `[@triggerName]` syntax, attach the animation that you just defined to
one or more elements in the component's template.
+makeExample('animations/ts/app/hero-list-basic.component.ts', 'template')(format=".")
:marked
Here we've applied the animation trigger to every element repeated by an `ngFor`. Each of
the repeated elements will animate independently. We're binding the value of the
attribute to the expression `hero.state`. We expect it to always be either `inactive`
or `active`, since that's what we have defined animation states for.
Here, the animation trigger applies to every element repeated by an `ngFor`. Each of
the repeated elements animates independently. The value of the
attribute is bound to the expression `hero.state` and is always either `active` or `inactive`.
With this setup, an animated transition is shown whenever a hero object changes state!
With this setup, an animated transition appears whenever a hero object changes state.
Here's the full component implementation:
+makeExample('animations/ts/app/hero-list-basic.component.ts')
:marked
## States and Transitions
## States and transitions
Angular animations are defined in terms of logical **states** and **transitions**
Angular animations are defined as logical **states** and **transitions**
between states.
An animation state is a string value that we define in our application code. In the example
above we used the states `'active'` and `'inactive'` based on the logical state of
hero objects. The source of the state can be a simple object attribute as it was in this case,
or it can be a value computed in a method. The important thing is that we can read it into the
An animation state is a string value that you define in your application code. In the example
above, the states `'active'` and `'inactive'` are based on the logical state of
hero objects. The source of the state can be a simple object attribute, as it was in this case,
or it can be a value computed in a method. The important thing is that you can read it into the
component's template.
We can define *styles* for each animation state:
You can define *styles* for each animation state:
+makeExample('animations/ts/app/hero-list-basic.component.ts', 'states')(format=".")
:marked
These `state` definitions specify the *end styles* of each state.
They are applied to the element once it has transitioned to that state, and will stay
*as long as it remains in that state*. In that sense, we are defining more than just
animations here. We're actually defining what styles the element has in different states.
They are applied to the element once it has transitioned to that state, and stay
*as long as it remains in that state*. In effect, you're defining what styles the element has in different states.
Once we have states, we can define *transitions* between the states. Each transition
After you define states, you can define *transitions* between the states. Each transition
controls the timing of switching between one set of styles and the next:
+makeExample('animations/ts/app/hero-list-basic.component.ts', 'transitions')(format=".")
figure.image-display
img(src="/resources/images/devguide/animations/ng_animate_transitions_inactive_active.png" alt="In Angular animations we defines states and transitions between states" width="400")
img(src="/resources/images/devguide/animations/ng_animate_transitions_inactive_active.png" alt="In Angular animations you define states and transitions between states" width="400")
:marked
If we have the same timing configuration for several transitions, we can combine
If several transitions have the same timing configuration, you can combine
them into the same `transition` definition:
+makeExample('animations/ts/app/hero-list-combined-transitions.component.ts', 'transitions')(format=".")
:marked
When we have the same timing for both directions of a transition, as we do in the previous
example, we can use the `<=>` shorthand syntax:
When both directions of a transition have the same timing, as in the previous
example, you can use the shorthand syntax `<=>`:
+makeExample('animations/ts/app/hero-list-twoway.component.ts', 'transitions')(format=".")
:marked
Sometimes we have styles that we want to apply during an animation but not keep around
after it finishes. We can define such styles inline in the `transition`. In this example,
You can also apply a style during an animation but not keep it around
after the animation finishes. You can define such styles inline, in the `transition`. In this example,
the element receives one set of styles immediately and is then animated to the next.
When the transition finishes, none of these styles will be kept because they're not
When the transition finishes, none of these styles are kept because they're not
defined in a `state`.
+makeExample('animations/ts/app/hero-list-inline-styles.component.ts', 'transitions')(format=".")
@ -141,7 +135,7 @@ figure.image-display
### The wildcard state `*`
The `*` ("wildcard") state matches *any* animation state. This is useful for defining styles and
transitions that should apply regardless of which state the animation is in. For example:
transitions that apply regardless of which state the animation is in. For example:
* The `active => *` transition applies when the element's state changes from `active` to anything else.
* The `* => *` transition applies when *any* change between two states takes place.
@ -153,10 +147,10 @@ figure.image-display
:marked
### The `void` state
There's one special state called `void` that may apply to any animation. It applies
when the element is *not* attached to a view. This may be because it has not yet been
added or because it has been removed. The `void` state is useful for defining "enter" and
"leave" animations.
The special state called `void` can apply to any animation. It applies
when the element is *not* attached to a view, perhaps because it has not yet been
added or because it has been removed. The `void` state is useful for defining enter and
leave animations.
For example the `* => void` transition applies when the element leaves the view,
regardless of what state it was in before it left.
@ -167,11 +161,11 @@ figure.image-display
:marked
The wildcard state `*` also matches `void`.
## Example: Entering and Leaving
## Example: Entering and leaving
figure
img(src="/resources/images/devguide/animations/animation_enter_leave.gif" alt="Enter and leave animations" align="right" style="width:250px;" )
:marked
Using the `void` and `*` states we can define transitions that animate the
Using the `void` and `*` states you can define transitions that animate the
entering and leaving of elements:
* Enter: `void => *`
@ -180,17 +174,17 @@ figure
+makeExample('animations/ts/app/hero-list-enter-leave.component.ts', 'animationdef')(format=".")
:marked
Note that in this case we have the styles applied to the void state directly in the
transition definitions, and not in a separate `state(void)` definition. We do this because
we want the transforms to be different on enter and leave: The element enters from the left
Note that in this case the styles are applied to the void state directly in the
transition definitions, and not in a separate `state(void)` definition. Thus, the transforms
are different on enter and leave: the element enters from the left
and leaves to the right.
## Example: Entering and Leaving from Different States
## Example: Entering and leaving from different states
figure
img(src="/resources/images/devguide/animations/animation_enter_leave_states.gif" alt="Enter and leave animations combined with state animations" align="right" style="width:200px" )
:marked
We can also combine this animation with the earlier state transition animation by
using the hero state as the animation state. What this will let us do is configure
You can also combine this animation with the earlier state transition animation by
using the hero state as the animation state. This lets you configure
different transitions for entering and leaving based on what the state of the hero
is:
@ -199,7 +193,7 @@ figure
* Inactive hero leave: `inactive => void`
* Active hero leave: `active => void`
We now have fine-grained control over each transition:
This gives you fine-grained control over each transition:
figure.image-display
img(src="/resources/images/devguide/animations/ng_animate_transitions_inactive_active_void.png" alt="This example transitions between active, inactive, and void states" width="400")
@ -208,54 +202,53 @@ figure.image-display
+makeExample('animations/ts/app/hero-list-enter-leave-states.component.ts', 'animationdef')(format=".")
:marked
## Animatable Properties and Units
## Animatable properties and units
Since Angular's animation support builds on top of Web Animations, we can animate any property
Since Angular's animation support builds on top of Web Animations, you can animate any property
that the browser considers *animatable*. This includes positions, sizes, transforms, colors,
borders and many others. The W3C maintains
[a list of animatable properties](https://www.w3.org/TR/css3-transitions/#animatable-properties).
borders, and many others. The W3C maintains
[a list of animatable properties](https://www.w3.org/TR/css3-transitions/#animatable-properties)
on its [CSS Transitions page](https://www.w3.org/TR/css3-transitions).
For positional properties that have a numeric value, we can define a unit by providing
For positional properties that have a numeric value, you can define a unit by providing
the value as a string with the appropriate suffix:
* `'50px'`
* `'3em'`
* `'100%'`
For most dimensional properties we can also just define a number which is then assumed to be
in pixels:
If you don't provide a unit when specifying dimension, Angular assumes the default of `px`:
* `50` is the same as saying `'50px'`
## Automatic Property Calculation
## Automatic property calculation
figure
img(src="/resources/images/devguide/animations/animation_auto.gif" alt="Animation with automated height calculation" align="right" style="width:220px;margin-left:20px" )
:marked
Sometimes the value of a dimensional style property that we want to
animate is not known until at runtime. For example, it is quite common for elements
to have widths and heights that depend on their content and the screen size. These
properties are often tricky to animate with CSS.
Sometimes you don't know the value of a dimensional style property until runtime.
For example, elements often have widths and heights that
depend on their content and the screen size. These properties are often tricky
to animate with CSS.
With Angular we can use a special `*` property value in these cases. What it means
is that the value of this property will be computed at runtime and then plugged into
the animation.
In these cases, you can use a special `*` property value so that the value of the
property is computed at runtime and then plugged into the animation.
The "leave" animation in this example takes whatever height the element has before it
In this example, the leave animation takes whatever height the element has before it
leaves and animates from that height to zero:
+makeExample('animations/ts/app/hero-list-auto.component.ts', 'animationdef')(format=".")
:marked
## Animation Timing
## Animation timing
There are three timing properties we can tune for every animated transition:
The duration, the delay, and the easing function. They are all combined into
There are three timing properties you can tune for every animated transition:
the duration, the delay, and the easing function. They are all combined into
a single transition *timing string*.
### Duration
The duration controls how long the animation takes to run from start to finish.
We can define a duration in three ways:
You can define a duration in three ways:
* As a plain number, in milliseconds: `100`
* In a string, as milliseconds: `'100ms'`
@ -263,8 +256,8 @@ figure
### Delay
The delay controls how long to wait after an animation triggers before the
transition actually begins. We can define one by adding it in the same string
The delay controls the length of time between the animation trigger and the beginning
of the transition. You can define one by adding it to the same string
following the duration. It also has the same format options as the duration:
* Wait for 100ms and then run for 200ms: `'0.2s 100ms'`
@ -272,8 +265,8 @@ figure
### Easing
The [easing function](http://easings.net/) controls how the animation accelerates
and decelerates during its runtime. For example, using an `ease-in` function means
the animation begins relatively slowly but then picks up speed as it progresses. We
and decelerates during its runtime. For example, an `ease-in` function causes
the animation to begin relatively slowly but pick up speed as it progresses. You
can control the easing by adding it as a *third* value in the string after the duration
and the delay (or as the *second* value when there is no delay):
@ -285,67 +278,66 @@ figure
:marked
### Example
Here are a couple of custom timings in action. Both "enter" and "leave" last for
Here are a couple of custom timings in action. Both enter and leave last for
200 milliseconds but they have different easings. The leave begins after a
slight delay:
+makeExample('animations/ts/app/hero-list-timings.component.ts', 'animationdef')(format=".")
:marked
## Multi-Step Animations with Keyframes
## Multi-step animations with keyframes
figure
img(src="/resources/images/devguide/animations/animation_multistep.gif" alt="Animations with some bounce implemented with keyframes" align="right" style="width:220px;margin-left:20px" )
:marked
With animation *keyframes* we can go beyond a simple transition between two
sets of styles to a more intricate animation that goes through one or more
intermediate styles in between.
Animation *keyframes* go beyond a simple transition to a more intricate animation
that goes through one or more intermediate styles when transitioning between two sets of styles.
For each keyframe, we can specify an *offset* that defines at which point
For each keyframe, you specify an *offset* that defines at which point
in the animation that keyframe applies. The offset is a number between zero,
which marks the beginning of the animation, and one, which marks the end.
In this example we add some "bounce" to our enter and leave animations with
This example adds some "bounce" to the enter and leave animations with
keyframes:
+makeExample('animations/ts/app/hero-list-multistep.component.ts', 'animationdef')(format=".")
:marked
Note that the offsets are *not* defined in terms of absolute time. They are relative
measures from 0 to 1. The final timeline of the animation will based on the combination
measures from zero to one. The final timeline of the animation is based on the combination
of keyframe offsets, duration, delay, and easing.
Defining offsets for keyframes is optional. If we omit them, offsets with even
Defining offsets for keyframes is optional. If you omit them, offsets with even
spacing are automatically assigned. For example, three keyframes without predefined
offsets will receive offsets `0`, `0.5`, and `1`.
offsets receive offsets `0`, `0.5`, and `1`.
:marked
## Parallel Animation Groups
## Parallel animation groups
figure
img(src="/resources/images/devguide/animations/animation_groups.gif" alt="Parallel animations with different timings, implemented with groups" align="right" style="width:220px;margin-left:20px" )
:marked
We've already seen how we can animate multiple style properties at the same time:
Just put all of them into the same `style()` definition!
You've seen how to animate multiple style properties at the same time:
just put all of them into the same `style()` definition.
But we may also want to configure different *timings* for animations that happen
in parallel. For example, we may want to animate two CSS properties but use a
But you may also want to configure different *timings* for animations that happen
in parallel. For example, you may want to animate two CSS properties but use a
different easing function for each one.
For this we can use animation *groups*. In this example we use groups both on
enter and leave so that we can use two different timing configurations. Both
are applied to the same element in parallel, but run independent of each other:
For this you can use animation *groups*. In this example, using groups both on
enter and leave allows for two different timing configurations. Both
are applied to the same element in parallel, but run independently of each other:
+makeExample('animations/ts/app/hero-list-groups.component.ts', 'animationdef')(format=".")
:marked
One group animates the element transform and width. The other animates the opacity.
One group animates the element transform and width; the other group animates the opacity.
:marked
## Animation callbacks
A callback is fired when an animation is started and also when it is done.
In the keyframes example, we have a `trigger` called `@flyInOut`. There we can hook
those callbacks like:
In the keyframes example, you have a `trigger` called `@flyInOut`. There you can hook
those callbacks like this:
+makeExample('animations/ts/app/hero-list-multistep.component.ts', 'template')(format=".")