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How to detect screen orientation change in Xamarin Forms? I need to change the view on orientation change, what should I do to trigger a change on orientation change? Providing a link or sample code would be very helpful.

Thanks in advance

Stefan
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Femil Shajin
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2 Answers2

14

I tried it with dependency injection, but no succes yet. Right now, I solved it like this:

  • Use OnSizeAllocated(double, double) for changing the screen on orientation changes.
  • Use a Singleton for storing the current orientation.

Xamarin.Forms Page

protected override void OnSizeAllocated(double width, double height)
{
    base.OnSizeAllocated(width, height);

    if (DeviceInfo.IsOrientationPortrait() && width > height || !DeviceInfo.IsOrientationPortrait() && width < height)
        {
            // Orientation got changed! Do your changes here
        }
}

Singleton Class

public class DeviceInfo
{
    protected static DeviceInfo _instance;
    double width;
    double height;

    static DeviceInfo()
    {
        _instance = new DeviceInfo();
    }
    protected DeviceInfo()
    {
    }

    public static bool IsOrientationPortrait() 
    {
        return _instance.height > _instance.width;
    }

    public static void SetSize(double width, double height)
    {
        _instance.width = width;
        _instance.height = height;
    }
}
bkardol
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13

Just add this to your Page, or better yet your BasePage:

 static bool IsPortrait(Page p) { return p.Width < p.Height; }
Ian Vink
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    Useful tip for code that will need to cope with different orientations, though that doesn't show how to *trigger* some action when orientation changes - some type of event listener (or "on" method) is needed. – ToolmakerSteve Sep 26 '15 at 12:44