Class KeyFrame

java.lang.Object

javafx.animation.KeyFrame

public final class KeyFrame extends Object

Defines target values at a specified point in time for a set of variables that are interpolated along a Timeline.

The developer controls the interpolation of a set of variables for the interval between successive key frames by providing a target value and an Interpolator associated with each variable. The variables are interpolated such that they will reach their target value at the specified time. An onFinished function is invoked on each KeyFrame if one is provided. A KeyFrame can optionally have a name, which will result in a cuepoint that is automatically added to the Timeline.

Since:

JavaFX 2.0

See Also:

Constructor Summary

Constructor	Description
`KeyFrame(Duration time, String name, KeyValue... values)`	Constructor of `KeyFrame`
`KeyFrame(Duration time, String name, EventHandler<ActionEvent> onFinished, Collection<KeyValue> values)`	Constructor of `KeyFrame`
`KeyFrame(Duration time, String name, EventHandler<ActionEvent> onFinished, KeyValue... values)`	Constructor of `KeyFrame`
`KeyFrame(Duration time, KeyValue... values)`	Constructor of `KeyFrame`
`KeyFrame(Duration time, EventHandler<ActionEvent> onFinished, KeyValue... values)`	Constructor of `KeyFrame`

Method Summary

Modifier and Type	Method	Description
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`String`	`getName()`	Returns the `name` of this `KeyFrame`.
`EventHandler<ActionEvent>`	`getOnFinished()`	Returns the `onFinished` event handler of this `KeyFrame`.
`Duration`	`getTime()`	Returns the time offset of this `KeyFrame`.
`Set<KeyValue>`	`getValues()`	Returns an immutable `Set` of `KeyValue` instances.
`int`	`hashCode()`	Returns a hash code for this `KeyFrame` object.
`String`	`toString()`	Returns a string representation of this `KeyFrame` object.

Methods declared in class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Details

KeyFrame

public KeyFrame(Duration time, String name, EventHandler<ActionEvent> onFinished, Collection<KeyValue> values)

Constructor of KeyFrame

If a passed in KeyValue is null or a duplicate, it will be ignored.

Parameters:: time - the time; name - the name; onFinished - the onFinished; values - a ObservableList of KeyValue instances
Throws:: NullPointerException - if time is null; IllegalArgumentException - if time is invalid (see time)

KeyFrame

public KeyFrame(Duration time, String name, EventHandler<ActionEvent> onFinished, KeyValue... values)

Constructor of KeyFrame

If a passed in KeyValue is null or a duplicate, it will be ignored.

Parameters:: time - the time; name - the name; onFinished - the onFinished; values - the KeyValue instances
Throws:: NullPointerException - if time is null; IllegalArgumentException - if time is invalid (see time)

KeyFrame

public KeyFrame(Duration time, EventHandler<ActionEvent> onFinished, KeyValue... values)

Constructor of KeyFrame

Parameters:: time - the time; onFinished - the onFinished; values - the KeyValue instances
Throws:: NullPointerException - if time is null; IllegalArgumentException - if time is invalid (see time)

KeyFrame

public KeyFrame(Duration time, String name, KeyValue... values)

Constructor of KeyFrame

Parameters:: time - the time; name - the name; values - the KeyValue instances
Throws:: NullPointerException - if time is null; IllegalArgumentException - if time is invalid (see time)

KeyFrame

public KeyFrame(Duration time, KeyValue... values)

Constructor of KeyFrame

Parameters:: time - the time; values - the KeyValue instances
Throws:: NullPointerException - if time is null; IllegalArgumentException - if time is invalid (see time)

Method Details

getTime

public Duration getTime()

Returns the time offset of this KeyFrame. The returned Duration defines the time offset within a single cycle of a Timeline at which the KeyValues will be set and at which the onFinished function variable will be called.

The time of a KeyFrame has to be greater than or equal to Duration.ZERO and it cannot be Duration.UNKNOWN. Note: While the unit of time is a millisecond, the granularity depends on the underlying operating system and will in general be larger. For example animations on desktop systems usually run with a maximum of 60fps which gives a granularity of ~17 ms.

Returns:: the time offset

getValues

public Set<KeyValue> getValues()

Returns an immutable Set of KeyValue instances. A KeyValue defines a target and the desired value that should be interpolated at the specified time of this KeyFrame.

Returns:: an immutable Set of KeyValue instances

getOnFinished

public EventHandler<ActionEvent> getOnFinished()

Returns the onFinished event handler of this KeyFrame. The onFinished event handler is a function that is called when the elapsed time on a cycle passes the specified time of this KeyFrame. The onFinished function variable will be called if the elapsed time passes the indicated value, even if it never equaled the time value exactly.

Returns:: the onFinished event handler

getName

public String getName()

Returns the name of this KeyFrame. If a named KeyFrame is added to a Timeline, a cuepoint with the name and the time of the KeyFrame will be added automatically. If the KeyFrame is removed, the cuepoint will also be removed.

Returns:: the name

toString

public String toString()

Returns a string representation of this KeyFrame object.

Overrides:: toString in class Object
Returns:: the string representation

hashCode

public int hashCode()

Returns a hash code for this KeyFrame object.

Overrides:: hashCode in class Object
Returns:: the hash code

equals

public boolean equals(Object obj)

Indicates whether some other object is "equal to" this one. Two KeyFrames are considered equal, if their time, onFinished, and values are equal.

Overrides:: equals in class Object
Returns:: true if this is the same as obj, otherwise false

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Documentation extracted from JavaFX API Documentation.
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