PerformanceObserver extension type
The PerformanceObserver
interface is used to observe performance
measurement events and be notified of new PerformanceEntry as they are
recorded in the browser's performance timeline.
API documentation sourced from MDN Web Docs.
- on
- Implemented types
- Available extensions
Constructors
- PerformanceObserver(PerformanceObserverCallback callback)
-
factory
Properties
- hashCode → int
-
The hash code for this object.
no setterinherited
- isDefinedAndNotNull → bool
-
Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension
no setter - isNull → bool
-
Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension
Whether this value corresponds to JavaScriptnull
.no setter - isTruthy → JSBoolean
-
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of!!
in JavaScript.this
no setter - isUndefined → bool
-
Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension
Whether this value corresponds to JavaScriptundefined
.no setter - isUndefinedOrNull → bool
-
Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension
no setter - not → JSBoolean
-
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of!
in JavaScript.this
no setter - runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
Methods
-
add(
JSAny? any) → JSAny -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
+any
-
and(
JSAny? any) → JSAny? -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
&&any
-
callMethod<
R extends JSAny?> (JSAny method, [JSAny? arg1, JSAny? arg2, JSAny? arg3, JSAny? arg4]) → R -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Callsmethod
on this JSObject with up to four arguments. -
callMethodVarArgs<
R extends JSAny?> (JSAny method, [List< JSAny?> ? arguments]) → R -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Callsmethod
on this JSObject with a variable number ofarguments
. -
dartify(
) → Object? -
Available on JSAny?, provided by the JSAnyUtilityExtension extension
Converts a JavaScript value to the Dart equivalent if possible. -
delete(
JSAny property) → JSBoolean -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Deletes the property with keyproperty
from this JSObject. -
disconnect(
) → void -
The
disconnect()
method of the PerformanceObserver interface is used to stop the performance observer from receiving any PerformanceEntry events. -
divide(
JSAny? any) → JSAny -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
/any
-
equals(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
==any
-
exponentiate(
JSAny? any) → JSAny -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
**any
-
getProperty<
R extends JSAny?> (JSAny property) → R -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
The value of the property keyproperty
of this JSObject. -
greaterThan(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
>any
-
greaterThanOrEqualTo(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
>=any
-
has(
String property) → bool -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Shorthand helper for hasProperty to check whether this JSObject contains the property keyproperty
, but takes and returns a Dart value. -
hasProperty(
JSAny property) → JSBoolean -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Whether or not this JSObject contains the property keyproperty
. -
instanceof(
JSFunction constructor) → bool -
Available on JSAny?, provided by the JSAnyUtilityExtension extension
Whether thisJSAny?
is aninstanceof
constructor
. -
instanceOfString(
String constructorName) → bool -
Available on JSAny?, provided by the JSAnyUtilityExtension extension
Whether thisJSAny?
is aninstanceof
the constructor that is defined byconstructorName
, which is looked up in the globalContext. -
isA<
T extends JSAny?> () → bool -
Available on JSAny?, provided by the JSAnyUtilityExtension extension
Whether thisJSAny?
is an instance of the JavaScript type that is declared byT
. -
lessThan(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
<any
-
lessThanOrEqualTo(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
<=any
-
modulo(
JSAny? any) → JSAny -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
%any
-
multiply(
JSAny? any) → JSAny -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
*any
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a nonexistent method or property is accessed.
inherited
-
notEquals(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
!=any
-
observe(
[PerformanceObserverInit options]) → void -
The
observe()
method of the PerformanceObserver interface is used to specify the set of performance entry types to observe. -
or(
JSAny? any) → JSAny? -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
||any
-
setProperty(
JSAny property, JSAny? value) → void -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Write thevalue
of property keyproperty
of this JSObject. -
strictEquals(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
===any
-
strictNotEquals(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
!==any
-
subtract(
JSAny? any) → JSAny -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
-any
-
takeRecords(
) → PerformanceEntryList -
The
takeRecords()
method of the PerformanceObserver interface returns the current list of PerformanceEntry stored in the performance observer, emptying it out. -
toString(
) → String -
A string representation of this object.
inherited
-
typeofEquals(
String typeString) → bool -
Available on JSAny?, provided by the JSAnyUtilityExtension extension
Whether the result oftypeof
on thisJSAny?
istypeString
. -
unsignedRightShift(
JSAny? any) → JSNumber -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
>>>any
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited
-
operator [](
String property) → JSAny? -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Shorthand helper for getProperty to get the value of the property keyproperty
of this JSObject, but takes and returns a Dart value. -
operator []=(
String property, JSAny? value) → void -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Shorthand helper for setProperty to write thevalue
of the property keyproperty
of this JSObject, but takes a Dart value.
Static Properties
-
supportedEntryTypes
→ JSArray<
JSString> -
The static
supportedEntryTypes
read-only property of the PerformanceObserver interface returns an array of the PerformanceEntry.entryType values supported by the user agent.no setter