property

Property object

app.project.item(index).layer(index).propertySpec

Description

The Property object contains value, keyframe, and expression information about a particular AE property of a layer. An AE property is a value, often animatable, of an effect, mask, or transform within an individual layer. For examples of how to access properties, see PropertyBase object and PropertyGroup.property().

Property is a subclass of PropertyBase. All methods and attributes of PropertyBase, in addition to those listed below, are available when working with Property.

Note

JavaScript objects commonly referred to as “properties” are called “attributes” in this guide, to avoid confusion with the After Effects definition of property.

Examples

Get and set the value of opacity:

var myProperty = myLayer.opacity;
// opacity has propertyValueType of OneD, and is stored as a float
myProperty.setValue(50); //set opacity to 50%
// Variable my Opacity is a float value
var myOpacity = myProperty.value;

Get and set the value of a position:

var myProperty = myLayer.position;
// position has propertyValueType of ThreeD_SPATIAL, and is stored as an array of 3 floats
myProperty.setValue([10.0, 30.0, 0.0]);
// Variable my Position is an array of 3 floats
var myPosition = myProperty.value;

Change the value of a mask shape to be open instead of closed:

var myMask = mylayer.mask(1);
var myProperty = myMask.maskPath;
myShape = myProperty.value;
myShape.closed = false;
myProperty.setValue(myShape);

Get the value of a color at a particular time. A color is stored as an array of four floats, [r, g, b, opacity]. This sets the value of the red component of a light’s color at time 4 to be half of that at time 2:

var myProperty = myLight.color;
var colorValue = myProperty.valueAtTime(2, true);
colorValue[0] = 0.5 * colorValue[0];
myProperty.setValueAtTime(4, colorValue);

Check that a scale calculated by an expression at time 3.5 is the expected value of [10,50]:

var myProperty = myLayer.scale;
// false value of preExpression means evaluate the expression
var scaleValue = myProperty.valueAtTime(3.5, false);

if (scaleValue[0] === 10 && scaleValue[1] === 50) {
    alert("hurray");
} else {
    alert("oops");
}

Keyframe a rotation from 0 to 90 and back again. The animation is 10 seconds, and the middle keyframe is at the 5 second mark. Rotation properties are stored as a OneD value:

var myProperty = myLayer.rotation;
myProperty.setValueAtTime(0, 0);
myProperty.setValueAtTime(5, 90);
myProperty.setValueAtTime(10, 0);

Change the key frame values for the first three keyframes of some sourcetext:

var myProperty = myTextLayer.sourceText;
if (myProperty.numKeys < 3) {
    alert("error, I thought there were 3 keyframes");
} else {
    myProperty.setValueAtKey(1, newTextDocument("keynumber1"));
    myProperty.setValueAtKey(2, newTextDocument("keynumber2"));
    myProperty.setValueAtKey(3, newTextDocument("keynumber3"));
}

Set values using the convenience syntax for position, scale, color, or source text:

// These two are equivalent. The second fills in a default of 0.
myLayer.position.setValue([20, 30, 0]);
myLayer.position.setValue([20, 30]);
// These two are equivalent. The second fills in a defaultof 100.
myLayer.scale.setValue([50, 50, 100]);
myLayer.scale.setValue([50, 50]);
// These two are equivalent. The second fills in a defaultof 1.0
myLight.color.setValue([0.8, 0.3, 0.1, 1.0]);
myLight.color.setValue([0.8, 0.3, 0.1]);
// These two are equivalent. The second creates a TextDocument
myTextLayer.sourceText.setValue(newTextDocument("foo"));
myTextLayer.sourceText.setValue("foo");

---

Attributes

Property.alternateSource

app.project.item(index).layer(index).propertySpec.alternateSource

Note

This functionality was added in After Effects 18.0 (2021)

Description

The value is null when:

• The alternate source is not set for the associated layer.
• The property cannot be used to set an alternate source.

Use Property.canSetAlternateSource to determine if the property is a Media Replacement Essential Property.

All Media Replacement Layers have an alternate source item that can be set.

A layer is “marked” for media replacement when the layer is added to the Essential Graphics Panel (see AVLayer.addToMotionGraphicsTemplate() or AVLayer.addToMotionGraphicsTemplateAs()).

• If present, the render workflow will pick up the alternate source while rendering the layer.
• If the alternate source for the layer is not set, then the source layer of the Media Replacement control is used for rendering (this is the normal workflow).

Use Property.setAlternateSource() to change the value.

Type

AVItem object; read-only.

---

Property.canSetAlternateSource

app.project.item(index).layer(index).propertySpec.canSetAlternateSource

Note

This functionality was added in After Effects 18.0 (2021)

Description

Test whether the property is an Essential Property that supports Media Replacement.

Returns true if the property allows Media Replacement, otherwise false.

Type

Boolean; read-only.

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Property.canSetExpression

app.project.item(index).layer(index).propertySpec.canSetExpression

Description

When true, the named property is of a type whose expression can be set by a script. See also Property expression attribute.

Type

Boolean; read-only.

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Property.canVaryOverTime

app.project.item(index).layer(index).propertySpec.canVaryOverTime

Description

When true, the named property can vary over time—that is, keyframe values or expressions can be written to this property.

Type

Boolean; read-only.

---

Property.dimensionsSeparated

app.project.item(index).layer(index).propertySpec.dimensionsSeparated

Description

When true, the property’s dimensions are represented as separate properties. For example, if the layer’s position is represented as X Position and Y Position properties in the Timeline panel, the Position property has this attribute set to true.

Tip

This attribute applies only when the isSeparationLeader attribute is true.

Type

Boolean; read/write.

---

Property.essentialPropertySource

app.project.item(index).layer(index).essentialProperty.property(index).essentialPropertySource

Note

This functionality was added in After Effects 22.0 (2022)

Description

Instance property on an Essential Property object which returns the original source Property which was used to create the Essential Property.

Type

Can be either:

• A read/write Property object, in the case that the source object used to create the Essential Property was a Property
• A read/write AVLayer object, in the case that the source object used to create the Essential Property was a Media Replacement Footage item
• null if called on a non-Essential Property

Example

var firstComp = app.project.item(1);
var opacityProp = firstComp.layer(1).property("Transform").property("Opacity");

opacityProp.addToMotionGraphicsTemplate(firstComp);

var secondComp = app.project.item(2);
secondComp.layers.add(firstComp);

var essentialOpacity = secondComp.layer(1).essentialProperty.property(1);
if (essentialOpacity.essentialPropertySource == opacityProp) {
    alert("You can get the source Property from an Essential Property!");
}

---

Property.expression

app.project.item(index).layer(index).propertySpec.expression

Description

The expression for the named property. Writeable only when canSetExpression for the named property is true. When you specify a value for this attribute, the string is evaluated.

• If the string contains a valid expression, expressionEnabled becomes true.
• If the string does not contain a valid expression, an error is generated, and expressionEnabled becomes false.
• If you set the attribute to the empty string, expressionEnabled becomes false, but no error is generated.

Type

String; read/write if canSetExpression for the named property is true.

---

Property.expressionEnabled

app.project.item(index).layer(index).propertySpec.expressionEnabled

Description

When true, the named property uses its associated expression to generate a value. When false, the keyframe information or static value of the property is used. This attribute can be set to true only if canSetExpression for the named property is true and expression contains a valid expression string.

Type

Boolean; read/write.

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Property.expressionError

app.project.item(index).layer(index).propertySpec.expressionError

Description

Contains the error, if any, generated by evaluation of the string most recently set in expression. If no expression string has been specified, or if the last expression string evaluated without error, contains the empty string ("").

Type

String; read-only.

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Property.hasMax

app.project.item(index).layer(index).propertySpec.hasMax

Description

When true, there is a maximum permitted value for the named property; otherwise false.

Type

Boolean; read-only.

---

Property.hasMin

app.project.item(index).layer(index).propertySpec.hasMin

Description

When true, there is a minimum permitted value for the named property; otherwise false.

Type

Boolean; read-only.

---

Property.isDropdownEffect

app.project.item(index).layer(index).propertySpec.isDropdownEffect

Note

This functionality was added in After Effects 17.0.1 (2020)

Description

When true, the property is the Menu property of a Dropdown Menu Control effect and can have its items updated with setPropertyParameters.

Examples

appliedEffect.property("Menu").isDropdownEffect;    // true
appliedEffect.property("Color").isDropdownEffect;   // false
appliedEffect.property("Feather").isDropdownEffect; // false

Type

Boolean; read-only.

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Property.isSeparationFollower

app.project.item(index).layer(index).propertySpec.isSeparationFollower

Description

When true, the property represents one of the separated dimensions for a multidimensional property. For example, the X Position property has this attribute set to true.

Tip

The original, consolidated, multidimensional property is the “separation leader” and the new, separated, single-dimensional properties are its “separation followers”.

Type

Boolean; read-only.

---

Property.isSeparationLeader

app.project.item(index).layer(index).propertySpec.isSeparationLeader

Description

When true, the property is multidimensional and can be separated. For example, the Position property has this attribute set to true.

Tip

The original, consolidated, multidimensional property is the “separation leader” and the new, separated, single-dimensional properties are its “separation followers”.

Type

Boolean; read-only.

---

Property.isSpatial

app.project.item(index).layer(index).propertySpec.isSpatial

Description

When true, the named property defines a spatial value. Examples are position and effect point controls.

Type

Boolean; read-only.

---

Property.isTimeVarying

app.project.item(index).layer(index).propertySpec.isTimeVarying

Description

When true, the named property is time varying — that is, it has keyframes or an enabled expression. When this attribute is true, the attribute canVaryOverTime must also be true.

Type

Boolean; read-only.

---

Property.maxValue

app.project.item(index).layer(index).propertySpec.maxValue

Description

The maximum permitted value of the named property. If the hasMax attribute is false, an exception occurs, and an error is generated.

Type

Floating-point value; read-only.

---

Property.minValue

app.project.item(index).layer(index).propertySpec.minValue

Description

The minimum permitted value of the named property. If the hasMin attribute is false, an exception occurs, and an error is generated.

Type

Floating-point value; read-only.

---

Property.numKeys

app.project.item(index).layer(index).propertySpec.numKeys

Description

The number of keyframes in the named property. If the value is 0, the property is not being keyframed.

Type

Integer; read-only.

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Property.propertyIndex

app.project.item(index).layer(index).propertySpec.propertyIndex

Description

The position index of the named property. The first property is at index position 1.

Type

Integer; read-only.

---

Property.propertyValueType

app.project.item(index).layer(index).propertySpec.propertyValueType

Description

The type of value stored in the named property. The PropertyValueType enumeration has one value for each type of data that can be stored in or retrieved from a property. Each type of data is stored and retrieved in a different kind of structure. All property objects store data according to one of these categories. For example, a 3D spatial property (such as a layer’s position) is stored as an array of three floating-point values. When setting a value for position, pass in such an array, as follows: mylayer.property("position").setValue([10, 20, 0]);

In contrast, a shape property (such as a layer’s mask shape) is stored as a Shape object. When setting a value for a shape, pass a Shape object, as follows:

var myShape = new Shape();
myShape.vertices = [[0,0], [0,100], [100,100], [100,0]];
var myMask = mylayer.property("ADBE Mask Parade").property(1);
myMask.property("ADBE Mask Shape").setValue(myShape);

Type

A PropertyValueType enumerated value; read/write. One of:

• PropertyValueType.NO_VALUE: Stores no data.
• PropertyValueType.ThreeD_SPATIAL: Array of three floating-point positional values. For example, an Anchor Point value might be [10.0, 20.2, 0.0]
• PropertyValueType.ThreeD: Array of three floating-point quantitative values. For example, a Scale value might be [100.0, 20.2, 0.0]
• PropertyValueType.TwoD_SPATIAL: Array of 2 floating-point positional values. For example, an Anchor Point value might be [5.1, 10.0]
• PropertyValueType.TwoD: Array of 2 floating-point quantitative values. For example, a Scale value might be [5.1, 100.0]
• PropertyValueType.OneD: A floating-point value.
• PropertyValueType.COLOR:Array of 4 floating-point values in the range [0.0..1.0]. For example, [0.8, 0.3, 0.1, 1.0]
• PropertyValueType.CUSTOM_VALUE : Custom property value, such as the Histogram property for the Levels effect.
• PropertyValueType.MARKER: MarkerValue object
• PropertyValueType.LAYER_INDEX: Integer; a value of 0 means no layer.
• PropertyValueType.MASK_INDEX: Integer; a value of 0 means no mask.
• PropertyValueType.SHAPE: Shape object
• PropertyValueType.TEXT_DOCUMENT: TextDocument object

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Property.selectedKeys

app.project.item(index).layer(index).propertySpec.selectedKeys

Description

The indices of all the selected keyframes in the named property. If no keyframes are selected, or if the property has no keyframes, returns an empty array.

Type

Array of integers; read-only.

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Property.separationDimension

app.project.item(index).layer(index).propertySpec.separationDimension

Description

For a separated follower, the dimension number it represents in the multidimensional leader. The first dimension starts at 0. For example, the Y Position property has a separationDimension value of 1; X Position has a value of 0.

Type

Integer; read-only.

---

Property.separationLeader

app.project.item(index).layer(index).propertySpec.separationLeader

Description

The original multidimensional property for this separated follower. For example, if the current property is Y Position, this attribute’s value points to the Position property.

Tip

The original, consolidated, multidimensional property is the “separation leader” and the new, separated, single-dimensional properties are its “separation followers”.

Type

Property object; read-only.

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Property.unitsText

app.project.item(index).layer(index).propertySpec.unitsText

Description

The text description of the units in which the value is expressed.

Type

String; read-only.

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Property.value

app.project.item(index).layer(index).propertySpec.value

Description

The value of the named property at the current time.

• If expressionEnabled is true, returns the evaluated expression value.
• If there are keyframes, returns the keyframed value at the current time.
• Otherwise, returns the static value.

The type of value returned depends on the property value type. See examples for Property object.

Type

A value appropriate for the type of the property (see Property.propertyValueType); read-only.

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Methods

Property.addKey()

app.project.item(index).layer(index).propertySpec.addKey(time)

Description

Adds a new keyframe or marker to the named property at the specified time and returns the index of the new keyframe.

Parameters

Parameter	Type	Description
time	Floating-point value	The time, in seconds, at which to add the keyframe. The beginning of the composition is 0.

Returns

Integer; the index of the new keyframe or marker.

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Property.addToMotionGraphicsTemplate()

app.project.item(index).layer(index).propertySpec.addToMotionGraphicsTemplate(comp)

Note

This functionality was added in After Effects 15.0 (CC 2018)

Description

Adds the property to the Essential Graphics panel for the specified composition.

Returns true if the property is successfully added, otherwise false.

If the property is not added, it is either because it is not one of the supported property types or the property has already been added to the EGP for that composition. After Effects will present a warning dialog if the property cannot be added to the EGP.

Use the Property.canAddToMotionGraphicsTemplate() method to test whether the property can be added to a Motion Graphics template.

Parameters

Parameter	Type	Description
comp	CompItem	The composition that you wish to add the property to.

Returns

Boolean.

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Property.addToMotionGraphicsTemplateAs()

app.project.item(index).layer(index).propertySpec.addToMotionGraphicsTemplateAs(comp, name)

Note

This functionality was added in After Effects 16.1 (CC 2019)

Description

Adds the property to the Essential Graphics panel for the specified composition, but with an additional option to give the EGP property a custom name.

Returns true if the property is successfully added, otherwise false.

If the property is not added, it is either because it is not one of the supported property types or the property has already been added to the EGP for that composition. After Effects will present a warning dialog if the property cannot be added to the EGP.

Use the Property.canAddToMotionGraphicsTemplate() method to test whether the property can be added to a Motion Graphics template.

Parameters

Parameter	Type	Description
comp	CompItem	The composition that you wish to add the property to.
name	String	The new name.

Returns

Boolean.

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Property.canAddToMotionGraphicsTemplate()

app.project.item(index).layer(index).propertySpec.canAddToMotionGraphicsTemplate(comp)

Note

This functionality was added in After Effects 15.0 (CC 2018)

Description

Test whether or not the property can be added to the Essential Graphics panel for the specified composition.

Returns true if the property can be added, otherwise false.

If the property can not be added, it is either because it is not one of the supported property types or the property has already been added to the EGP for that composition. After Effects will present a warning dialog if the property cannot be added to the EGP.

Supported property types are:

• Checkbox
• Color
• Numerical Slider (i.e., a single-value numerical property, such as Transform > Opacity or the Slider Control expression control effect)
• Source Text

Parameters

Parameter	Type	Description
comp	CompItem	The composition that you wish to add the property to.

Returns

Boolean.

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Property.getSeparationFollower()

app.project.item(index).layer(index).propertySpec.getSeparationFollower(dim)

Description

For a separated, multidimensional property, retrieves a specific follower property. For example, you can use this method on the Position property to access the separated X Position and Y Position properties

Tip

This attribute applies only when the isSeparationLeader attribute is true.

Parameters

Parameter	Type	Description
dim	Integer	The dimension number (starting at 0).

Returns

Property object, or an error if the property is not multidimensional or does not have the specified dimension.

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Property.isInterpolationTypeValid()

app.project.item(index).layer(index).propertySpec.isInterpolationTypeValid(type)

Description

Returns true if the named property can be interpolated using the specified keyframe interpolation type.

Parameters

Type

A KeyframeInterpolationType enumerated value; one of:

• KeyframeInterpolationType.LINEAR
• KeyframeInterpolationType.BEZIER
• KeyframeInterpolationType.HOLD

Returns

Boolean.

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Property.keyInInterpolationType()

app.project.item(index).layer(index).propertySpec.keyInInterpolationType(keyIndex)

Description

Returns the ‘in’ interpolation type for the specified keyframe.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.

Returns

A KeyframeInterpolationType enumerated value; one of:

• KeyframeInterpolationType.LINEAR
• KeyframeInterpolationType.BEZIER
• KeyframeInterpolationType.HOLD

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Property.keyInSpatialTangent()

app.project.item(index).layer(index).propertySpec.keyInSpatialTangent(keyIndex)

Description

Returns the incoming spatial tangent for the specified keyframe, if the named property is spatial (that is, the value type is TwoD_SPATIALorThreeD_SPATIAL).

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.

Returns

Array of floating-point values:

• If the property value type is PropertyValueType.TwoD_SPATIAL, the array contains 2 floating-point values.
• If the property value type is PropertyValueType.ThreeD_SPATIAL, the array contains 3 floating-point values.
• If the property value type is neither of these types, an exception is generated.

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Property.keyInTemporalEase()

app.project.item(index).layer(index).propertySpec.keyInTemporalEase(keyIndex)

Description

Returns the incoming temporal ease for the specified keyframe.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.

Returns

Array of KeyframeEase objects:

• If the property value type is PropertyValueType.TwoD, the array contains 2 objects.
• If the property value type is PropertyValueType.ThreeD, the array contains 3 objects.
• For any other value type, the array contains 1 object.

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Property.keyLabel()

app.project.item(index).layer(index).propertySpec.keyLabel(keyIndex)

Note

This functionality was added in After Effects 22.6.

Description

The label color for the keyframe. Colors are represented by their number (0 for None, or 1 to 16 for one of the preset colors in the Labels preferences).

Read only. Keyframe color labels can be set by setLabelAtKey.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.

Returns

Integer (0 to 16); read only.

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Property.keyOutInterpolationType()

app.project.item(index).layer(index).propertySpec.keyOutInterpolationType(keyIndex)

Description

Returns the outgoing interpolation type for the specified keyframe.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.

Returns

A KeyframeInterpolationType enumerated value; one of:

• KeyframeInterpolationType.LINEAR
• KeyframeInterpolationType.BEZIER
• KeyframeInterpolationType.HOLD

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Property.keyOutSpatialTangent()

app.project.item(index).layer(index).propertySpec.keyOutSpatialTangent(keyIndex)

Description

Returns the outgoing spatial tangent for the specified keyframe.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.

Returns

Array of floating-point values:

• If the property value type is PropertyValueType.TwoD_SPATIAL, the array contains 2 floating-point values.
• If the property value type is PropertyValueType.ThreeD_SPATIAL, the array contains 3 floating-point values.
• If the property value type is neither of these types, an exception is generated.

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Property.keyOutTemporalEase()

app.project.item(index).layer(index).propertySpec.keyOutTemporalEase(keyIndex)

Description

Returns the outgoing temporal ease for the specified keyframe.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.

Returns

Array of KeyframeEase objects:

• If the property value type is PropertyValueType.TwoD, the array contains 2 objects.
• If the property value type is PropertyValueType.ThreeD, the array contains 3 objects.
• For any other value type, the array contains 1 object.

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Property.keyRoving()

app.project.item(index).layer(index).propertySpec.keyRoving(keyIndex)

Description

Returns true if the specified keyframe is roving. The first and last keyframe in a property cannot rove; if you try to set roving for one of these, the operation is ignored, and keyRoving() continues to return false. If the property value type is neither TwoD_SPATIAL nor ThreeD_SPATIAL, an exception is generated.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.

Returns

Boolean.

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Property.keySelected()

app.project.item(index).layer(index).propertySpec.keySelected(keyIndex)

Description

Returns true if the specified keyframe is selected.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.

Returns

Boolean.

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Property.keySpatialAutoBezier()

app.project.item(index).layer(index).propertySpec.keySpatialAutoBezier(keyIndex)

Description

Returns true if the specified keyframe has spatial auto-Bezier interpolation. (This type of interpolation affects this keyframe only if keySpatialContinuous(keyIndex) is also true.) If the property value type is neither TwoD_SPATIAL nor ThreeD_SPATIAL, an exception is generated.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.

Returns

Boolean.

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Property.keySpatialContinuous()

app.project.item(index).layer(index).propertySpec.keySpatialContinuous(keyIndex)

Description

Returns true if the specified keyframe has spatial continuity. If the property value type is neither TwoD_SPATIAL nor ThreeD_SPATIAL, an exception is generated.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.

Returns

Boolean.

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Property.keyTemporalAutoBezier()

app.project.item(index).layer(index).propertySpec.keyTemporalAutoBezier(keyIndex)

Description

Returns true if the specified keyframe has temporal auto-Bezier interpolation. Temporal auto-Bezier interpolation affects this keyframe only if the keyframe interpolation type is KeyframeInterpolationType.BEZIER for both keyInInterpolationType(keyIndex) and keyOutInterpolationType(keyIndex).

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.

Returns

Boolean.

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Property.keyTemporalContinuous()

app.project.item(index).layer(index).propertySpec.keyTemporalContinuous(keyIndex)

Description

Returns true if the specified keyframe has temporal continuity. Temporal continuity affects this keyframe only if keyframe interpolation type is KeyframeInterpolationType.BEZIER for both keyInInterpolationType(keyIndex) and keyOutInterpolationType(keyIndex).

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.

Returns

Boolean.

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Property.keyTime()

app.project.item(index).layer(index).propertySpec.keyTime(keyIndex) app.project.item(index).layer(index).propertySpec.keyTime(markerComment)

Description

Finds the specified keyframe or marker and returns the time at which it occurs. If no keyframe or marker can be found that matches the argument, this method generates an exception, and an error is displayed.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.
markerComment	String	The comment attached to a marker (see MarkerValue.comment attribute).

Returns

Floating-point value.

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Property.keyValue()

app.project.item(index).layer(index).propertySpec.keyValue(keyIndex)

app.project.item(index).layer(index).propertySpec.keyValue(markerComment)

Description

Finds the specified keyframe or marker and returns its current value. If no keyframe or marker can be found that matches the argument, this method generates an exception, and an error is displayed.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.
markerComment	String	The comment attached to a marker (see MarkerValue.comment attribute).

Returns

Returns the value of the type corresponding to the PropertyValueType.

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Property.nearestKeyIndex()

app.project.item(index).layer(index).propertySpec.nearestKeyIndex(time)

Description

Returns the index of the keyframe nearest to the specified time.

Parameters

Parameter	Type	Description
time	Floating-point value	The time, in seconds. The beginning of the composition is 0.

Returns

Integer.

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Property.removeKey()

app.project.item(index).layer(index).propertySpec.removeKey(keyIndex)

Description

Removes the specified keyframe from the named property. If no keyframe with the specified index exists, generates an exception and displays an error. When a keyframe is removed, the remaining index numbers change. To remove more than one keyframe, you must start with the highest index number and work down to the lowest to ensure that the remaining indices reference the same keyframe after each removal.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.

Returns

Nothing.

---

Property.setAlternateSource()

app.project.item(index).layer(index).propertySpec.setAlternateSource(newSource)

Note

This functionality was added in After Effects 18.0 (2021)

Description

Set the alternate source for this property.

The Property object and the input parameters for the AVItem that is being called needs to be Media Replacement compatible for the action to go through.

• Use the AVItem.isMediaReplacementCompatible method to test whether the AVItem can be used as an alternate source for Media Replacement.
• Use Property.canSetAlternateSource to test if the property allows Media Replacement.

Parameters

Parameter	Type	Description
newSource	AVItem object	The new source AVItem.

Returns

Nothing.

---

Property.setInterpolationTypeAtKey()

app.project.item(index).layer(index).propertySpec.setInterpolationTypeAtKey(keyIndex, inType[, outType])

Description

Sets the in and out interpolation types for the specified keyframe.

Parameters

Parameter	Type	Description
keyIndex	Integer	The index for the keyframe, in the range [1..numKeys], as returned by the addKey or nearestKeyIndex.
inType	KeyframeInterpolationType enum.	The incoming interpolation type. One of:
		- KeyframeInterpolationType.LINEAR
		- KeyframeInterpolationType.BEZIER
		- KeyframeInterpolationType.HOLD
outType	KeyframeInterpolationType enum.	Optional. The outgoing interpolation type. If not supplied, the ‘out’ type is set to the inType value. One of:
		- KeyframeInterpolationType.LINEAR
		- KeyframeInterpolationType.BEZIER
		- KeyframeInterpolationType.HOLD

Returns

Nothing.

---

Property.setLabelAtKey()

app.project.item(index).layer(index).propertySpec.setLabelAtKey(keyIndex, labelIndex)

Note

This functionality was added in After Effects 22.6 (2022)

Description

Set the label color for the keyframe. Colors are represented by their number (0 for None, or 1 to 16 for one of the preset colors in the Labels preferences).

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.
labelIndex	Integer, in the range [0..16]	The index for the new label value.

Returns

Nothing.

---

Property.setPropertyParameters()

app.project.item(index).layer(index).propertySpec.setPropertyParameters(items)

Note

This functionality was added in After Effects 17.0.1 (2020)

Description

Sets parameters for a Dropdown Menu Control’s Menu Property. This method will overwrite the existing set of Menu items with the provided array of strings.

• The Dropdown Menu Control effect’s Menu property is the only property that allows parameters to be set.
• To check if a property allows parameters to be set, check with isDropdownEffect before calling this method.
• An exception is raised whenever this method fails.

Parameters

Parameter	Type	Description
items	Array of strings	Values which will replace the existing menu entries in a Dropdown Menu Control.
		- Only strings are allowed.
		- Empty item strings are not allowed.
		- Duplicate item strings are not allowed.
		- The character "\" is not allowed in the item strings.
		- The string "(-" can be specified as of the item strings, to create a separator line in the dropdown menu. The separator lines will claim an index for each of themselves.

Tip

For example: Specifying the item strings in Japanese while running the script on an English system will create a dropdown effect with illegible characters in the item strings.

Example

var dropdownItems = [
    "First Item",
    "Second Item",
    "(-",
    "Another Item",
    "Last Item"
];

var dropdownEffect = layer.property("ADBE Effect Parade").addProperty("ADBE Dropdown Control");
dropdownEffect.property(1).setPropertyParameters(dropdownItems);

Returns

Property object, the updated Dropdown Menu Control’s Menu property.

---

Property.setRovingAtKey()

app.project.item(index).layer(index).propertySpec.setRovingAtKey(keyIndex, newVal)

Description

Turns roving on or off for the specified keyframe. The first and last keyframe in a property cannot rove; if you try to set roving for one of these, the operation is ignored, and keyRoving() continues to return false. If the property value type is neither TwoD_SPATIAL nor ThreeD_SPATIAL, an exception is generated.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.
newVal	Boolean	true to turn roving on, false to turn roving off.

Returns

Nothing.

---

Property.setSelectedAtKey()

app.project.item(index).layer(index).propertySpec.setSelectedAtKey(keyIndex, onOff)

Description

Selects or deselects the specified keyframe.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.
onOff	Boolean	true to select the keyframe, false to deselect it.

Returns

Nothing.

---

Property.setSpatialAutoBezierAtKey()

app.project.item(index).layer(index).propertySpec.setSpatialAutoBezierAtKey(keyIndex, newVal)

Description

Turns spatial auto-Bezier interpolation on or off for the specified keyframe. If the property value type is neither TwoD_SPATIAL nor ThreeD_SPATIAL, an exception is generated.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.
newVal	Boolean	true to turn spatial auto-Bezier on, false to turn it off.

Returns

Nothing.

---

Property.setSpatialContinuousAtKey()

app.project.item(index).layer(index).propertySpec.setSpatialContinuousAtKey(keyIndex, newVal)

Description

Turns spatial continuity on or off for the specified keyframe. If the property value type is neither TwoD_SPATIAL nor ThreeD_SPATIAL, an exception is generated.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.
newVal	Boolean	true to turn spatial auto-Bezier on, false to turn it off.

Returns

Nothing.

---

Property.setSpatialTangentsAtKey()

app.project.item(index).layer(index).propertySpec.setSpatialTangentsAtKey(keyIndex, inTangent[, outTangent])

Description

Sets the incoming and outgoing tangent vectors for the specified keyframe. If the property value type is neither TwoD_SPATIAL nor ThreeD_SPATIAL, an exception is generated.

Parameters

Parameter	Type	Description
keyIndex	Integer	The index for the keyframe, in the range [1..numKeys], as returned by the addKey or nearestKeyIndex.
inTangent	An array of 2 or 3 floating-point values.	The incoming tangent vector.
		- If the property value type is PropertyValueType.TwoD_SPATIAL, the array contains 2 values.
		- If the property value type is PropertyValueType.ThreeD_SPATIAL, the array contains 3 values.
outTangent	An array of 2 or 3 floating-point values.	Optional. The outgoing tangent vector. If not supplied, the out tangent is set to the inTangent value.
		- If the property value type is PropertyValueType.TwoD_SPATIAL, the array contains 2 values.
		- If the property value type is PropertyValueType.ThreeD_SPATIAL, the array contains 3 values.

Returns

Nothing.

---

Property.setTemporalAutoBezierAtKey()

app.project.item(index).layer(index).propertySpec.setTemporalAutoBezierAtKey(keyIndex, newVal)

Description

Turns temporal auto-Bezier interpolation on or off for the specified keyframe. When this is turned on, it affects this keyframe only if keySpatialContinuous(keyIndex) is also true.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.
newVal	Boolean	true to turn temporal auto-Bezier on, false to turn it off.

Returns

Nothing.

---

Property.setTemporalContinuousAtKey()

app.project.item(index).layer(index).propertySpec.setTemporalContinuousAtKey(keyIndex, newVal)

Description

Turns temporal continuity on or off for the specified keyframe. When temporal continuity is turned on, it affects this keyframe only if the keyframe interpolation type is KeyframeInterpolationType.BEZIER for both keyInInterpolationType(keyIndex) and keyOutInterpolationType(keyIndex).

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.
newVal	Boolean	true to turn temporal auto-Bezier on, false to turn it off.

Returns

Nothing.

---

Property.setTemporalEaseAtKey()

app.project.item(index).layer(index).propertySpec.setTemporalEaseAtKey(keyIndex, inTemporalEase[, outTemporalEase])

Description

Sets the incoming and outgoing temporal ease for the specified keyframe. See KeyframeEase object.

Parameters

Parameter	Type	Description
keyIndex	Integer	The index for the keyframe, in the range [1..numKeys], as returned by the addKey or nearestKeyIndex.
inTemporalEase	An array of 1, 2, or 3 KeyframeEase objects	The incoming temporal ease.
		- If the property value type is PropertyValueType.TwoD, the array contains 2 objects.
		- If the property value type is PropertyValueType.ThreeD, the array contains 3 objects.
		- For all other value types, the array contains 1 object.
outTemporalEase	An array of 1, 2, or 3 KeyframeEase objects	Optional. The outgoing temporal ease. If not supplied, the outgoing ease is set to the inTemporalEase value.
		- If the property value type is PropertyValueType.TwoD, the array contains 2 objects.
		- If the property value type is PropertyValueType.ThreeD, the array contains 3 objects.
		- For all other value types, the array contains 1 object.

Returns

Nothing.

---

Property.setValue()

app.project.item(index).layer(index).propertySpec.setValue(newValue)

Description

Sets the static value of a property that has no keyframes. If the named property has keyframes, this method generates an exception and displays an error. To set the value of a property with keyframes, use Property.setValueAtTime() or Property.setValueAtKey().

Parameters

Parameter	Type	Description
newValue	Value	A value appropriate for the type of property being set; see Property.propertyValueType.

Returns

Nothing.

---

Property.setValueAtKey()

app.project.item(index).layer(index).propertySpec.setValueAtKey(keyIndex, newValue)

Description

Finds the specified keyframe and sets its value. If the named property has no keyframes, or no keyframe with the specified index, this method generates an exception and displays an error.

Parameters

Parameter	Type	Description
keyIndex	Integer, in the range [1..numKeys]	The index for the keyframe, as returned by the addKey or nearestKeyIndex.
newValue	Value	A value appropriate for the type of property being set; see Property.propertyValueType.

Returns

Nothing.

---

Property.setValueAtTime()

app.project.item(index).layer(index).propertySpec.setValueAtTime(time, newValue)

Description

Sets the value of a keyframe at the specified time. Creates a new keyframe for the named property, if one does not currently exist for the specified time, and sets its value.

Parameters

Parameter	Type	Description
time	Floating-point value	The time, in seconds, at which to set the value. The beginning of the composition is 0.
newValue	Value	A value appropriate for the type of property being set; see Property.propertyValueType.

Returns

Nothing.

---

Property.setValuesAtTimes()

app.project.item(index).layer(index).propertySpec.setValuesAtTimes(times, newValues)

Description

Sets values for a set of keyframes at specified times. Creates a new keyframe for the named property, if one does not currently exist for a specified time, and sets its value. Times and values are expressed as arrays; the arrays must be of the same length.

Parameters

Parameter	Type	Description
times	Array of floating-point values	An array of times, in seconds. The beginning of the composition is 0.
newValues	Array of values	A array of values appropriate for the type of property being set; see Property.propertyValueType.

Returns

Nothing.

---

Property.valueAtTime()

app.project.item(index).layer(index).propertySpec.valueAtTime(time, preExpression)

Description

The value of the named property as evaluated at the specified time. Note that the type of value returned is not made explicit; it will be of a different type, depending on the property evaluated.

Tip

As After Effects 13.6, this method now waits for time-intensive expressions, like sampleImage, to finish evaluating before it returns the result.

Parameters

Parameter	Type	Description
time	Floating-point value	The time, in seconds, at which to set the value. The beginning of the composition is 0.
preExpression	Boolean	If the property has an expression and this is true, return the value for the specified time without applying the expression to it. When false, return the result of evaluating the expression for the specified time. Ignored if the property does not have an associated expression.

Returns

A value appropriate for the type of the property (see “Property propertyValueType attribute” on page 138).