dart - flutter- 如何知道设备的 DeviceOrientation 是向上还是向下？

Question

当我旋转屏幕时，它会随着屏幕一起旋转相机，所以我得到倒置相机屏幕。

return new AspectRatio(
    aspectRatio: controller.value.aspectRatio,
    child: new CameraPreview(controller),
  );

Answer 1

您可以使用 OrientationBuilder 构建响应式应用

OrientationBuilder(
  builder: (context, orientation) {
    return GridView.count(
      // Create a grid with 2 columns in portrait mode, or 3 columns in landscape mode.
      crossAxisCount: orientation == Orientation.portrait ? 2 : 3,
    );
  },
);

或

Orientation currentOrientation = MediaQuery.of(context).orientation;
if(currentOrientation == Orientation.portrait){
    /* ... */
}

要强制执行特定方向，请参阅此 https://stackoverflow.com/a/50322184/9664127

其他有用的链接:

https://flutter.io/cookbook/design/orientation/

https://docs.flutter.io/flutter/services/DeviceOrientation-class.html

https://medium.com/@kr1uz/how-to-restrict-device-orientation-in-flutter-65431cd35113

已更新

Flutter 目前不支持 'orientation sides'，但是这个插件可能在这方面有帮助 https://pub.dartlang.org/packages/native_device_orientation