rebuild method Null safety

void rebuild()

Cause the widget to update itself. In debug builds, also verify various invariants.

Called by the BuildOwner when BuildOwner.scheduleBuildFor has been called to mark this element dirty, by mount when the element is first built, and by update when the widget has changed.

Implementation

@pragma('vm:prefer-inline')
void rebuild() {
  assert(_lifecycleState != _ElementLifecycle.initial);
  if (_lifecycleState != _ElementLifecycle.active || !_dirty) {
    return;
  }
  assert(() {
    debugOnRebuildDirtyWidget?.call(this, _debugBuiltOnce);
    if (debugPrintRebuildDirtyWidgets) {
      if (!_debugBuiltOnce) {
        debugPrint('Building $this');
        _debugBuiltOnce = true;
      } else {
        debugPrint('Rebuilding $this');
      }
    }
    return true;
  }());
  assert(_lifecycleState == _ElementLifecycle.active);
  assert(owner!._debugStateLocked);
  Element? debugPreviousBuildTarget;
  assert(() {
    debugPreviousBuildTarget = owner!._debugCurrentBuildTarget;
    owner!._debugCurrentBuildTarget = this;
    return true;
  }());
  performRebuild();
  assert(() {
    assert(owner!._debugCurrentBuildTarget == this);
    owner!._debugCurrentBuildTarget = debugPreviousBuildTarget;
    return true;
  }());
  assert(!_dirty);
}