新双方德尔福Android开发。我如何检测屏幕的方向发生了变化？即，从纵向到横向，反之亦然？而且我怎么火过code当出现这种情况？比如我有一个图像大小在比方说在纵向模式下安全工程师，但当器件切换为横向，我希望它来调整，并采取了整个屏幕宽度。

New to both Delphi Android development. How do I detect that the screen orientation has changed? i.e. from Portrait to Landscape and vice versa? And how do I fire off code when this happens? For example I have an image sized at let's say 300x200 in portrait mode but when the device switches to landscape I want it to adjust and take up full screen width.

推荐答案

在您的形式实现的方法

procedure DoOrientationChanged(const Sender: TObject; const M: TMessage);

在这里你处理当前的方向。认购FORMCREATE这样的方向变化。

where you handle the current orientation. Subscribe for orientation changes in FormCreate like this

TMessageManager.DefaultManager.SubscribeToMessage(TOrientationChangedMessage, DoOrientationChanged);

和在FormDestroy退订这样的：

and unsubscribe in FormDestroy like this:

TMessageManager.DefaultManager.Unsubscribe(TOrientationChangedMessage, DoOrientationChanged);

要找出当前的屏幕方向只问IFMXScreenService：

To find out the current screen orientation just ask IFMXScreenService:

var
  screenService: IFMXScreenService;
begin
  if TPlatformServices.Current.SupportsPlatformService(IFMXScreenService, screenService) then begin
    case screenService.GetScreenOrientation of
      TScreenOrientation.Portrait: ;
      TScreenOrientation.Landscape: ;
      TScreenOrientation.InvertedPortrait: ;
      TScreenOrientation.InvertedLandscape: ;
    end;
  end;
end;