Stopwatch class Null safety

A stopwatch which measures time while it's running.

A stopwatch is either running or stopped. It measures the elapsed time that passes while the stopwatch is running.

When a stopwatch is initially created, it is stopped and has measured no elapsed time.

The elapsed time can be accessed in various formats using elapsed, elapsedMilliseconds, elapsedMicroseconds or elapsedTicks.

The stopwatch is started by calling start.

Example:

final stopwatch = Stopwatch();
print(stopwatch.elapsedMilliseconds); // 0
print(stopwatch.isRunning); // false
stopwatch.start();
print(stopwatch.isRunning); // true

To stop or pause the stopwatch, use stop. Use start to continue again when only pausing temporarily.

stopwatch.stop();
print(stopwatch.isRunning); // false
Duration elapsed = stopwatch.elapsed;
await Future.delayed(const Duration(seconds: 1));
assert(stopwatch.elapsed == elapsed); // No measured time elapsed.
stopwatch.start(); // Continue measuring.

The reset method sets the elapsed time back to zero. It can be called whether the stopwatch is running or not, and doesn't change whether it's running.

// Do some work.
stopwatch.stop();
print(stopwatch.elapsedMilliseconds); // Likely > 0.
stopwatch.reset();
print(stopwatch.elapsedMilliseconds); // 0

Constructors

Stopwatch()
Creates a Stopwatch in stopped state with a zero elapsed count.

Properties

elapsed Duration
The elapsedTicks counter converted to a Duration.
read-only
elapsedMicroseconds int
The elapsedTicks counter converted to microseconds.
read-only
elapsedMilliseconds int
The elapsedTicks counter converted to milliseconds.
read-only
elapsedTicks int
The elapsed number of clock ticks since calling start while the Stopwatch is running.
read-only
frequency int
Frequency of the elapsed counter in Hz.
read-only
hashCode int
The hash code for this object.
read-only, inherited
isRunning bool
Whether the Stopwatch is currently running.
read-only
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited

Methods

noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed.
inherited
reset() → void
Resets the elapsed count to zero.
start() → void
Starts the Stopwatch.
stop() → void
Stops the Stopwatch.
toString() String
A string representation of this object.
inherited

Operators

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