Dart API

Appearance

dart:html›Classes›Event

Event ​

class Event extends JavaScriptObject

Annotations: @Native.new("Event,InputEvent,SubmitEvent")

Implementers

Constructors ​

Event() factory ​

factory Event(String type, {bool canBubble = true, bool cancelable = true})
Implementation
dart
factory Event(String type, {bool canBubble = true, bool cancelable = true}) {
  return new Event.eventType(
    'Event',
    type,
    canBubble: canBubble,
    cancelable: cancelable,
  );
}

Event.eventType() factory ​

factory Event.eventType(
  String type,
  String name, {
  bool canBubble = true,
  bool cancelable = true,
})

Creates a new Event object of the specified type.

This is analogous to document.createEvent. Normally events should be created via their constructors, if available.

dart
var e = new Event.type('MouseEvent', 'mousedown', true, true);
Implementation
dart
factory Event.eventType(
  String type,
  String name, {
  bool canBubble = true,
  bool cancelable = true,
}) {
  final Event e = document._createEvent(type);
  e._initEvent(name, canBubble, cancelable);
  return e;
}

Properties ​

bubbles no setter ​

bool? get bubbles
Implementation
dart
bool? get bubbles native;

cancelable no setter ​

bool? get cancelable
Implementation
dart
bool? get cancelable native;

composed no setter ​

bool? get composed
Implementation
dart
bool? get composed native;

currentTarget no setter ​

EventTarget? get currentTarget
Implementation
dart
EventTarget? get currentTarget =>
    _convertNativeToDart_EventTarget(this._get_currentTarget);

defaultPrevented no setter ​

bool get defaultPrevented
Implementation
dart
bool get defaultPrevented native;

eventPhase no setter ​

int get eventPhase
Implementation
dart
int get eventPhase native;

hashCode no setter inherited ​

int get hashCode

Inherited from Interceptor.

Implementation
dart
int get hashCode => Primitives.objectHashCode(this);

isTrusted no setter ​

bool? get isTrusted
Implementation
dart
bool? get isTrusted native;

matchingTarget no setter ​

Element get matchingTarget

A pointer to the element whose CSS selector matched within which an event was fired. If this Event was not associated with any Event delegation, accessing this value will throw an UnsupportedError.

Implementation
dart
Element get matchingTarget {
  if (_selector == null) {
    throw new UnsupportedError(
      'Cannot call matchingTarget if this Event did'
      ' not arise as a result of event delegation.',
    );
  }
  Element? currentTarget = this.currentTarget as Element?;
  Element? target = this.target as Element?;
  var matchedTarget;
  do {
    if (target!.matches(_selector!)) return target;
    target = target.parent;
  } while (target != null && target != currentTarget!.parent);
  throw new StateError('No selector matched for populating matchedTarget.');
}

path no setter ​

List<EventTarget> get path
Implementation
dart
List<EventTarget> get path =>
    JS<bool>('bool', '!!#.composedPath', this) ? composedPath() : [];

runtimeType no setter inherited ​

Type get runtimeType

Inherited from Interceptor.

Implementation
dart
Type get runtimeType =>
    getRuntimeTypeOfInterceptorNotArray(getInterceptor(this), this);

target no setter ​

EventTarget? get target
Implementation
dart
EventTarget? get target => _convertNativeToDart_EventTarget(this._get_target);

timeStamp no setter ​

num? get timeStamp
Implementation
dart
num? get timeStamp native;

type no setter ​

String get type
Implementation
dart
String get type native;

Methods ​

composedPath() ​

List<EventTarget> composedPath()
Implementation
dart
List<EventTarget> composedPath() native;

noSuchMethod() inherited ​

dynamic noSuchMethod(Invocation invocation)

Invoked when a nonexistent method or property is accessed.

A dynamic member invocation can attempt to call a member which doesn't exist on the receiving object. Example:

dart
dynamic object = 1;
object.add(42); // Statically allowed, run-time error

This invalid code will invoke the noSuchMethod method of the integer 1 with an Invocation representing the .add(42) call and arguments (which then throws).

Classes can override noSuchMethod to provide custom behavior for such invalid dynamic invocations.

A class with a non-default noSuchMethod invocation can also omit implementations for members of its interface. Example:

dart
class MockList<T> implements List<T> {
  noSuchMethod(Invocation invocation) {
    log(invocation);
    super.noSuchMethod(invocation); // Will throw.
  }
}
void main() {
  MockList().add(42);
}

This code has no compile-time warnings or errors even though the MockList class has no concrete implementation of any of the List interface methods. Calls to List methods are forwarded to noSuchMethod, so this code will log an invocation similar to Invocation.method(#add, [42]) and then throw.

If a value is returned from noSuchMethod, it becomes the result of the original invocation. If the value is not of a type that can be returned by the original invocation, a type error occurs at the invocation.

The default behavior is to throw a NoSuchMethodError.

Inherited from Interceptor.

Implementation
dart
dynamic noSuchMethod(Invocation invocation) {
  throw NoSuchMethodError.withInvocation(this, invocation);
}

preventDefault() ​

void preventDefault()
Implementation
dart
void preventDefault() native;

stopImmediatePropagation() ​

void stopImmediatePropagation()
Implementation
dart
void stopImmediatePropagation() native;

stopPropagation() ​

void stopPropagation()
Implementation
dart
void stopPropagation() native;

toString() inherited ​

String toString()

A string representation of this object.

Some classes have a default textual representation, often paired with a static parse function (like int.parse). These classes will provide the textual representation as their string representation.

Other classes have no meaningful textual representation that a program will care about. Such classes will typically override toString to provide useful information when inspecting the object, mainly for debugging or logging.

Inherited from Interceptor.

Implementation
dart
String toString() => Primitives.objectToHumanReadableString(this);

Operators ​

operator ==() inherited ​

bool operator ==(Object other)

The equality operator.

The default behavior for all Objects is to return true if and only if this object and other are the same object.

Override this method to specify a different equality relation on a class. The overriding method must still be an equivalence relation. That is, it must be:

  • Total: It must return a boolean for all arguments. It should never throw.

  • Reflexive: For all objects o, o == o must be true.

  • Symmetric: For all objects o1 and o2, o1 == o2 and o2 == o1 must either both be true, or both be false.

  • Transitive: For all objects o1, o2, and o3, if o1 == o2 and o2 == o3 are true, then o1 == o3 must be true.

The method should also be consistent over time, so whether two objects are equal should only change if at least one of the objects was modified.

If a subclass overrides the equality operator, it should override the hashCode method as well to maintain consistency.

Inherited from Interceptor.

Implementation
dart
bool operator ==(Object other) => identical(this, other);

Constants ​

AT_TARGET ​

const int AT_TARGET

This event is being handled by the event target.

Other resources ​

Implementation
dart
static const int AT_TARGET = 2;

BUBBLING_PHASE ​

const int BUBBLING_PHASE

This event is bubbling up through the target's ancestors.

Other resources ​

Implementation
dart
static const int BUBBLING_PHASE = 3;

CAPTURING_PHASE ​

const int CAPTURING_PHASE

This event is propagating through the target's ancestors, starting from the document.

Other resources ​

Implementation
dart
static const int CAPTURING_PHASE = 1;