MediaQueryList class
A MediaQueryList object maintains a list of media queries on a document
, and handles sending notifications to listeners when the media queries on the document change.
This makes it possible to observe a document to detect when its media queries change, instead of polling the values periodically, if you need to programmatically detect changes to the values of media queries on a document.
@DocsEditable
@DomName('MediaQueryList')
class MediaQueryList native "MediaQueryList" {
@DomName('MediaQueryList.matches')
@DocsEditable
final bool matches;
@DomName('MediaQueryList.media')
@DocsEditable
final String media;
@DomName('MediaQueryList.addListener')
@DocsEditable
void addListener(MediaQueryListListener listener) native;
@DomName('MediaQueryList.removeListener')
@DocsEditable
void removeListener(MediaQueryListListener listener) native;
}
Extends
Interceptor > MediaQueryList
Properties
final int hashCode #
Get a hash code for this object.
All objects have hash codes. Hash codes are guaranteed to be the
same for objects that are equal when compared using the equality
operator ==. Other than that there are no guarantees about
the hash codes. They will not be consistent between runs and
there are no distribution guarantees.
If a subclass overrides hashCode it should override the
equality operator as well to maintain consistency.
int get hashCode => Primitives.objectHashCode(this);
Operators
bool operator ==(other) #
The equality operator.
The default behavior for all Objects is to return true if and
only if this and
other are the same object.
If a subclass overrides the equality operator it should override
the hashCode method as well to maintain consistency.
bool operator ==(other) => identical(this, other);
Methods
void addListener(MediaQueryListListener listener) #
Adds a new listener to the media query list. If the specified listener is already in the list, this method has no effect.
Parameters
listener- The
MediaQueryListListenerto invoke when the media query's evaluated result changes.
@DomName('MediaQueryList.addListener')
@DocsEditable
void addListener(MediaQueryListListener listener) native;
dynamic noSuchMethod(Invocation invocation) #
noSuchMethod is invoked when users invoke a non-existant method
on an object. The name of the method and the arguments of the
invocation are passed to noSuchMethod in an Invocation.
If noSuchMethod returns a value, that value becomes the result of
the original invocation.
The default behavior of noSuchMethod is to throw a
noSuchMethodError.
dynamic noSuchMethod(Invocation invocation) {
throw new NoSuchMethodError(
this,
_symbolToString(invocation.memberName),
invocation.positionalArguments,
_symbolMapToStringMap(invocation.namedArguments));
}
void removeListener(MediaQueryListListener listener) #
Removes a listener from the media query list. Does nothing if the specified listener isn't already in the list.
Parameters
listener- The
MediaQueryListListenerto stop calling on changes to the media query's evaluated result.
@DomName('MediaQueryList.removeListener')
@DocsEditable
void removeListener(MediaQueryListListener listener) native;
This page includes content from the
Mozilla Foundation that is graciously
licensed under a
Creative Commons: Attribution-Sharealike license.
Mozilla has no other association with Dart or dartlang.org. We
encourage you to improve the web by
contributing to
The Mozilla Developer Network.