Delphi/Firemonkey Change iOS Screen Rotation at Runtime

Delphi/Firemonkey Change iOS screen rotation at runtime

Ok this rotation had me digging deep into the iOS API to figure out how iOS manages orientation.

Because you can not fake a rotation or force a device certain device orientation in iOS in iOS you have quite a few orientations to consider

• Device Orientation
• Statusbar orientation
• UIViewcontroller orientation

The device orientation can not be forced or altered this will always show the orientation your device is in now.

The statusbar orientation however has always had the setStatusBarOrientation procedure you could call and spesify the orientation you wanted, but this was marked as deprecated, and thus was not working, but I didn't get a external exception when I called the function, which ment that it was still there, it just wasn't working.

then I read this :

The setStatusBarOrientation:animated: method is not deprecated outright. It now works only if the supportedInterfaceOrientations method of the top-most full-screen view controller returns 0

I then decided to try this

Application.FormFactor.Orientations := []; //the supportedInterfaceOrientations returns 0
App := TUIApplication.Wrap(TUIApplication.OCClass.sharedApplication);
win := TUIWindow.Wrap(App.windows.objectAtIndex(0));
App.setStatusBarOrientation(UIInterfaceOrientationLandscapeLeft);

And it works the statusbar orientation changes, but like mentioned above, this protocol is deprecated so at some stage it can/will fall away and this will no longer work.

but this only changed the rotation of the statusbar and all alertviews etc, but the actual content within the rootviewcontroller is still in the Portrait in my case of wanting to change to landscape.

I then tought if I would in Delphi would go to Application->Orientation-> Enable custom rotation and say landscape only then the App will only display in landscape, and it does perfectly because when the form is created and then rootViewcontroller is made the supportedInterface orientations that is returned is only landscape and the Viewcontroller goes to Landscape.

Because when your device changes device orientation the orientation is evaluated against the Viewcontroller's supportedinterfaceorientations, if the orientation is not supported it is simply not rotated.

But when a new rootviewcontroller is assigned the GUI has to be updated to display in that Viewcontrollers supported orientations, with that in mind, here is my fix/hack to change the orientation of your App to a orientation you want.

TL;DR

Uses: iOSapi.UIKit; 

procedure ChangeiOSorientation(toOrientation: UIInterfaceOrientation;
possibleOrientations: TScreenOrientations);
var
    win : UIWindow;
    App : UIApplication;
    viewController : UIViewController;
    oucon: UIViewController;
begin
    Application.FormFactor.Orientations := []; //Change supported orientations
    App := TUIApplication.Wrap(TUIApplication.OCClass.sharedApplication);
    win := TUIWindow.Wrap(App.windows.objectAtIndex(0)); //The first Windows is always the main Window

    App.setStatusBarOrientation(toOrientation);
    {After you have changed your statusbar orientation set the
    Supported orientation/orientations to whatever you need}
    Application.FormFactor.Orientations := possibleOrientations;
    viewController := TUIViewController.Wrap(TUIViewController.alloc.init);//dummy ViewController
    oucon := TUIViewController.Wrap(TUIViewController.alloc.init);
    {Now we are creating a new Viewcontroller now when it is created
     it will have to check what is the supported orientations}
    oucon := win.rootViewController;//we store all our current content to the new ViewController
    Win.setRootViewController(viewController);
    Win.makeKeyAndVisible;// We display the Dummy viewcontroller

    win.setRootViewController(oucon);
    win.makeKeyAndVisible; 
    {And now we Display our original Content in a new Viewcontroller 
     with our new Supported orientations} 
end;

All you have to do now is Call ChangeiOSorientation(toOrientation,possibleOrientations)

If you want it to go to Portrait but have landscape as a option

 ChangeiOSorientation(UIInterfaceOrientationPortrait,[TScreenOrientation.Portrait,TScreenOrientation.Landscape,TScreenOrientation.InvertedLandscape]);    

This is working on

• Delphi 10 Seattle
• iPhone 5 running iOS 9.0
• PA Server 17.0
• Xcode 7.1
• iPhoneOS 9.1 SDK

Screen orientation on iOS

This line:

if (TPlatformServices::Current->SupportsPlatformService(__uuidof(IFMXScreenService), Intf))

should be this instead:

if (TPlatformServices::Current->SupportsPlatformService(__uuidof(IFMXScreenService), &Intf))

Note the addition of the & operator in the last parameter. This is even stated in the documentation:

Note: Please consider that you need to add & before Intf, as you can see in the code sample above.

Also, Intf really should be declared to match the interface you are requesting, eg:

void __fastcall TForm1::Button1Click(TObject *Sender)
{
    _di_IFMXScreenService ScreenService;
    if (TPlatformServices::Current->SupportsPlatformService(__uuidof(IFMXScreenService), &ScreenService))
    {
        TScreenOrientations Orientation;
        Orientation << TScreenOrientation::Landscape;
        ScreenService->SetScreenOrientation(Orientation);
    }
}

How to prevent screen rotation with android development in delphi xe5 Firemonkey

Add FMX.Platform to your uses clause, and get rid of the redundant call to GetPlatformService():

uses
  ..., FMX.Platform;

procedure TLogin.FormCreate(Sender: TObject);
var
  ScreenService: IFMXScreenService;
  OrientSet: TScreenOrientations;
begin
  if TPlatformServices.Current.SupportsPlatformService(IFMXScreenService, IInterface(ScreenService)) then
  begin
    OrientSet := [TScreenOrientation.soLandscape];
    ScreenService.SetScreenOrientation(OrientSet);
  end;
end;

Firemonkey Listview & mobile screen orientation in Delphi 11

The Accessory, Detail and Text items have an Align property that can take values Center, Leading or Trailing. They are recalculated and adjust their position with changes in the screen orientation.

Additionally some items have a separate property, TextAlign, which sets the position for a text within the space of the Align result.

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