pumpAndSettle method Null safety
- [Duration duration = const Duration(milliseconds: 100)]
Repeatedly calls pump with the given
duration until there are no
longer any frames scheduled. This will call pump at least once, even if
no frames are scheduled when the function is called, to flush any pending
microtasks which may themselves schedule a frame.
This essentially waits for all animations to have completed.
If it takes longer that the given
timeout to settle, then the test will
fail (this method will throw an exception). In particular, this means that
if there is an infinite animation in progress (for example, if there is an
indeterminate progress indicator spinning), this method will throw.
The default timeout is ten minutes, which is longer than most reasonable finite animations would last.
If the function returns, it returns the number of pumps that it performed.
In general, it is better practice to figure out exactly why each frame is needed, and then to pump exactly as many frames as necessary. This will help catch regressions where, for instance, an animation is being started one frame later than it should.
Alternatively, one can check that the return value from this function matches the expected number of pumps.
Future<int> pumpAndSettle([ Duration duration = const Duration(milliseconds: 100), ]);