setExposureAndFocusPoint method

Future<void> setExposureAndFocusPoint(Offset position, BoxConstraints constraints)

Use the position to set exposure and focus. 通过点击点的 position 设置曝光和对焦。

Implementation

Future<void> setExposureAndFocusPoint(
  Offset position,
  BoxConstraints constraints,
) async {
  isFocusPointDisplays.value = false;
  if (enableScaledPreview) {
    // Ignore point update when the new point is less than 8% and higher than
    // 92% of the screen's height.
    if (position.dy < constraints.maxHeight / 12 ||
        position.dy > constraints.maxHeight / 12 * 11) {
      return;
    }
  }
  realDebugPrint(
    'Setting new exposure point (x: ${position.dx}, y: ${position.dy})',
  );
  lastExposurePoint.value = position;
  restartExposurePointDisplayTimer();
  currentExposureOffset.value = 0;
  currentExposureSliderOffset.value = 0;
  restartExposureFadeOutTimer();
  isFocusPointFadeOut.value = false;
  try {
    await Future.wait(<Future<void>>[
      wrapControllerMethod<void>(
        'setExposureOffset',
        () => controller.setExposureOffset(0),
      ),
      controller.setExposureOffset(0),
      if (controller.value.exposureMode == ExposureMode.locked)
        wrapControllerMethod<void>(
          'setExposureMode',
          () => controller.setExposureMode(ExposureMode.auto),
        ),
    ]);
    final Offset newPoint = lastExposurePoint.value!.scale(
      1 / constraints.maxWidth,
      1 / constraints.maxHeight,
    );
    await Future.wait(<Future<void>>[
      if (controller.value.exposurePointSupported)
        controller.setExposurePoint(newPoint),
      if (controller.value.focusPointSupported)
        controller.setFocusPoint(newPoint),
    ]);
  } catch (e, s) {
    handleErrorWithHandler(e, s, pickerConfig.onError);
  }
}