Keeping screen turned on for certain pages

Question

I am using a portable project so do not have direct access to native code.

I have an interface in my project that allows me to access native objects in the Android/iOS projects. We use this primarily for playing audio.

Android, for example, has things like

Window w = new Window();
w.SetFlags(WindowManagerFlags.Fullscreen, WindowManagerFlags.KeepScreenOn);

However the main issue would be accessing a Window object. I could pass a Xamarin.Forms.Page object to the native code, but there would be no way (I don't think) to cast it to a native Android Window object to access the flags.

Is there a way to do this with a portable project?

Answer: https://stackoverflow.com/a/53534562/7149454 – Nick Kovalsky Feb 11 '19 at 06:52 — Nick Kovalsky, Feb 11 '19 at 06:52

Tim Klingeleers · Accepted Answer · 2017-05-01T13:49:14.297

18

You can't do this without platform specific services or renderers. A portable project will have to call platform specific code in order to achieve this.

From that platform specific code, either as a DependencyService or Renderer, you can access the Window object through the Forms.Context. The Forms.Context is your Android Activity, through which you can reach the Window object.

On Android it works like this:

Android.Views.Window window = (Forms.Context as Activity).Window;
window.SetFlags(WindowManagerFlags.KeepScreenOn);

On iOS you can try this (Apple docs):

UIApplication.SharedApplication.IdleTimerDisabled = true;

edited May 01 '17 at 13:49

answered Apr 29 '17 at 09:42

Tim Klingeleers

2,834
14
20

Great, that seems to work perfectly! I suppose I should have asked about both... Any idea how this is done on iOS? Just a note, `window.SetFlags(WindowManagerFlags.Fullscreen, WindowManagerFlags.KeepScreenOn);` didn't seem to work, but `window.AddFlags(WindowManagerFlags.KeepScreenOn);` does work well – sosil May 01 '17 at 13:44
Oh, you are right, didn't notice that. I've updated the answer for iOS and fixed the Android version. – Tim Klingeleers May 01 '17 at 13:49
Ah ok, I was just giving that a shot right now, I'll let you know if it works – sosil May 01 '17 at 14:08
1

In Android now I get 'Forms.Context' is obsolete: 'Context is obsolete as of version 2.5. Please use a local context instead.' How do I have to do this without Forms.Context – Kees Dapperens May 10 '18 at 22:32
@KeesDapperens: You could use [this solution](https://stackoverflow.com/a/56523482/426227) for `DependencyService`. In a `Renderer` there is a `Context` parameter in the constructor. I used the `DependencyService` because with the `Renderer` changing back to the defaults (screen lock is on again) never happened. – testing Dec 14 '21 at 17:41

Emil · Answer 2 · 2021-12-16T13:33:12.053

Now there is a plugin doing exactly what Tim wrote

https://learn.microsoft.com/en-us/xamarin/essentials/screen-lock

simple source code is here

https://github.com/xamarin/Essentials/blob/main/Samples/Samples/ViewModel/KeepScreenOnViewModel.cs

using System.Windows.Input; using Xamarin.Essentials; using Xamarin.Forms;

namespace Samples.ViewModel
{
    public class KeepScreenOnViewModel : BaseViewModel
    {
        public KeepScreenOnViewModel()
        {
            RequestActiveCommand = new Command(OnRequestActive);
            RequestReleaseCommand = new Command(OnRequestRelease);
        }

        public bool IsActive => DeviceDisplay.KeepScreenOn;

        public ICommand RequestActiveCommand { get; }

        public ICommand RequestReleaseCommand { get; }

        void OnRequestActive()
        {
            DeviceDisplay.KeepScreenOn = true;

            OnPropertyChanged(nameof(IsActive));
        }

        void OnRequestRelease()
        {
            DeviceDisplay.KeepScreenOn = false;

            OnPropertyChanged(nameof(IsActive));
        }
    }
}

@testing github links can change often. Obviously was working at the time 3 years a go. I have updated the answer. — Emil, Dec 16 '21 at 13:34

score 0 · Answer 3 · answered Feb 11 '19 at 04:47

0

For Xamarin Forms Android. Renders file I included below code

Window window = (Forms.Context as Activity).Window;
window.AddFlags(WindowManagerFlags.KeepScreenOn);

answered Feb 11 '19 at 04:47

Kairat Koibagarov

1,385
15
9

Keeping screen turned on for certain pages

3 Answers3