FakeCaptureSession class

A CaptureSession that never touches a microphone.

This fake drives the same state as a real session: the recording flag, the frame stream, the rolling scope and the drop counters. As a result, a widget test can exercise the visualizer of a host. Frames arrive when a test calls emit or emitTone, and not when an audio thread produces them. This makes the timing exact instead of merely likely.

dispose leaves the same values readable as the real session. produced, dropped, pcmDropped and truncated answer after dispose and do not throw. As a result, a UI that reads a counter during teardown behaves the same here as it does against a microphone. The real session freezes its counters at dispose to manage this, because the C struct that supplied them is gone by then.

Implemented types

Constructors

FakeCaptureSession({CaptureConfig config = const CaptureConfig()})

Properties

config → CaptureConfig
final
dropped → int
Hops that the consumer was too slow to collect.
no setteroverride
emitted → List<CaptureFrame>
Every frame emitted since construction.
final
frames → Stream<CaptureFrame>
Reduced frames, in order.
no setteroverride
hashCode → int
The hash code for this object.
no setterinherited
isPaused → bool
Whether the device is stopped but the take is intact.
no setteroverride
isRecording → bool
no setteroverride
nextStartError ↔ Object?
If a test sets this field, start throws it.
getter/setter pair
pcmDropped → int
Samples that the audio ring dropped because the file writer was too slow.
no setteroverride
produced → int
Hops that the audio thread produced.
no setteroverride
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
scope → CaptureScope
A rolling window of recent frames, for a painter to draw.
final
startCount ↔ int
getter/setter pair
stopCount ↔ int
getter/setter pair
stopResult ↔ WaveformPeaks?
What stop returns. The default is peaks from the frames that this fake emitted.
getter/setter pair
truncated → bool
Whether the history is more than CaptureConfig.maxDuration.
no setteroverride

Methods

dispose() → Future<void>
override
dropFrames(int count) → void
Simulates a consumer that falls behind.
emit(CaptureFrame frame) → void
Publishes one frame, exactly as a drain does.
emitTone(int count, {double amplitude = 0.5}) → void
Publishes count frames at a steady amplitude from 0 to 1.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
pause() → Future<void>
Stops the device and keeps the take.
override
resume() → Future<void>
override
start() → Future<void>
override
stop() → Future<WaveformPeaks>
Stops the device and returns peaks for all the audio that it captured.
override
toString() → String
A string representation of this object.
inherited

Operators

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