This sample app guides you how you design and implement your app to support portrait mode. For more information, see Portrait Mode.

​By default, your app’s orientation will remain in landscape mode even if the TV device is rotated, which means a user will see 90 degrees rotated display. To make your app to support portrait mode, insert the supportPortraitMode property and set the property to true in the appinfo.json file of your app. You can also set the background color and the fit mode of the splash image. For more information about the splash image, see the splashColor property and the splashFitModeOnPortrait property in the appinfo.json.

The layout rotation might not be applied to your app if the screenOrientationChange event is raised before the event handler is added. To prevent this problem, you should check the TV screen's rotation using the webOSSystem.screenOrientation property during your app launch.

var orientation = webOSSystem.screenOrientation;
if (orientation === 'landscape' || orientation === 'reversed_landscape') {
  // Load horizontal layout
} else if (orientation === 'portrait' || orientation === 'reversed_portrait') {
  // Load vertical layout
} else {
  // Load default layout
}

The scenario for changing your app layout between the landscape and portrait modes is as follows:

1. When the TV screen is rotated, the app receives orientation information using the screenOrientationChange event handler.
2. The app asks the web engine to change the app’s window orientation by calling the webOSSystem.setWindowOrientation API.
3. The web engine rotates the window and raises the window resize event. When the app receives the window resize event, the app changes its layout.

// Step 1. Handling the screenOrientationChange event
document.addEventListener('screenOrientationChange', function (event) {
  console.log('handleScreenOrientationChange', event.screenOrientation);
  // Step 2. Calling the webOSSystem.setWindowOrientation API
  webOSSystem.setWindowOrientation(event.screenOrientation);
});

// Step 3. Handling the window resize event
document.addEventListener("resize", function () {
  // Change app layout
});

• landscape
  
• portrait