frame method Null safety

void frame(
  1. [dynamic frame]
)

Changes focus to another frame on the page. If frame is a: int: select by its zero-based index WebElement: select the frame for a previously found frame or iframe element. String: same as above, but only CSS id is provided. Note that this is not element id or frame id. not provided: selects the first frame on the page or the main document.

Throws NoSuchFrameException if the specified frame can't be found.

Implementation

void frame([/* int | WebElement | String */ frame]) {
  if (frame is int?) {
    _client.send(_handler.frame.buildSwitchByIdRequest(frame),
        _handler.frame.parseSwitchByIdResponse);
  } else if (frame is WebElement) {
    _client.send(_handler.frame.buildSwitchByElementRequest(frame.id),
        _handler.frame.parseSwitchByElementResponse);
  } else if (frame is String) {
    final frameId = _driver.findElement(By.id(frame)).id;
    _client.send(_handler.frame.buildSwitchByElementRequest(frameId),
        _handler.frame.parseSwitchByElementResponse);
  } else {
    throw 'Unsupported frame "$frame" with type ${frame.runtimeType}';
  }
}