ImageStream class

A handle to an image resource.

ImageStream represents a handle to a dart:ui.Image object and its scale (together represented by an ImageInfo object). The underlying image object might change over time, either because the image is animating or because the underlying image resource was mutated.

ImageStream objects can also represent an image that hasn't finished loading.

ImageStream objects are backed by ImageStreamCompleter objects.

The ImageCache will consider an image to be live until the listener count drops to zero after adding at least one listener. The ImageStreamCompleter.addOnLastListenerRemovedCallback method is used for tracking this information.

See also:

Mixed in types


Create an initially unbound image stream.


completer ImageStreamCompleter?
The completer that has been assigned to this image stream.
no setter
hashCode int
The hash code for this object.
no setterinherited
key Object
Returns an object which can be used with == to determine if this ImageStream shares the same listeners list as another ImageStream.
no setter
runtimeType Type
A representation of the runtime type of the object.
no setterinherited


addListener(ImageStreamListener listener) → void
Adds a listener callback that is called whenever a new concrete ImageInfo object is available. If a concrete image is already available, this object will call the listener synchronously.
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
removeListener(ImageStreamListener listener) → void
Stops listening for events from this stream's ImageStreamCompleter.
setCompleter(ImageStreamCompleter value) → void
Assigns a particular ImageStreamCompleter to this ImageStream.
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
toString({DiagnosticLevel minLevel =}) String
A string representation of this object.
toStringShort() String
A brief description of this object, usually just the runtimeType and the hashCode.


operator ==(Object other) bool
The equality operator.