Modulate the camera flash on a Lumia 920 Windows Phone 8 device

MainPageXAML.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.Windows;
using Microsoft.Phone.Controls;
using Microsoft.Phone.Shell;
using FlashKontrol.Resources;
using System.Windows.Media;
using Windows.Phone.Media.Capture;
using System.Windows.Threading;
using Windows.System.Threading;

 

namespace FlashKontrol
{   
   
    public partial class MainPage : PhoneApplicationPage
    {
        private AudioVideoCaptureDevice _captureDev;
        private const CameraSensorLocation _sensorLoc = CameraSensorLocation.Back;
        private IReadOnlyList<object> supportedCameraModes;
        private bool torchMode = false;
       
        private DispatcherTimer dispTimer;
        private ThreadPoolTimer periodicTimer;
        private bool flashFlag = false;

        // Constructor
        public MainPage()
        {
            InitializeComponent();
            InitializeCaptureDevice();
            SelectCaptureDevice();

            flashOff.IsEnabled = false;
            tspan.Text = "500";

            // Sample code to localize the ApplicationBar
            //BuildLocalizedApplicationBar();
        }

        private async void InitializeCaptureDevice()
        {
            _captureDev = await GetCaptureDevice();
        }

        private async Task<AudioVideoCaptureDevice> GetCaptureDevice()
        {
            AudioVideoCaptureDevice captureDevice = await AudioVideoCaptureDevice.OpenAsync(_sensorLoc, AudioVideoCaptureDevice.GetAvailableCaptureResolutions(_sensorLoc).First());
            return captureDevice;
        }

        private void SelectCaptureDevice()
        {           
            try
            {
                supportedCameraModes = AudioVideoCaptureDevice.GetSupportedPropertyValues(_sensorLoc, KnownCameraAudioVideoProperties.VideoTorchMode);
                torchMode = supportedCameraModes.ToList().Contains((UInt32)VideoTorchMode.On);
                if (torchMode)
                {
                    _captureDev.SetProperty(KnownCameraAudioVideoProperties.VideoTorchPower, AudioVideoCaptureDevice.GetSupportedPropertyRange(_sensorLoc, KnownCameraAudioVideoProperties.VideoTorchPower).Max);
                }

            }
            catch (Exception ex)
            {

            }
        }

        private void BitOn()
        {
            _captureDev.SetProperty(KnownCameraAudioVideoProperties.VideoTorchMode, VideoTorchMode.On);
        }

        private void BitOff()
        {
            _captureDev.SetProperty(KnownCameraAudioVideoProperties.VideoTorchMode, VideoTorchMode.Off);
        }


        private void Button_Click(object sender, RoutedEventArgs e)
        {
            if (torchMode)
            {
                BitOn();
                flashOn.IsEnabled = false;
                flashOff.IsEnabled = true;
            }
        }

        private void Button_Click_1(object sender, RoutedEventArgs e)
        {
            if (torchMode)
            {
                if (this.dispTimer != null)
                {
                    this.dispTimer.Stop();
                    timerOn.IsEnabled = true;
                    BitOff();

                    flashOn.IsEnabled = true;
                    flashOff.IsEnabled = false;
                    poolTime.IsEnabled = true;
                }
                else
                {
                    BitOff();
                    flashOn.IsEnabled = true;
                    flashOff.IsEnabled = false;
                }

                if (periodicTimer != null)
                {
                    periodicTimer.Cancel();
                    flashOn.IsEnabled = true;
                    flashOff.IsEnabled = false;
                    poolTime.IsEnabled = true;
                }

                _captureDev.Dispose();
            }
        }

        private void timerOn_Click(object sender, RoutedEventArgs e)
        {

            if (this.dispTimer == null)
            {
                this.dispTimer = new DispatcherTimer();
                this.dispTimer.Interval = TimeSpan.FromMilliseconds(Convert.ToDouble(tspan.Text));
               
                this.dispTimer.Tick += new EventHandler(dispTimerEventHandler);
            }

            flashOn.IsEnabled = false;
            flashOff.IsEnabled = true;
            timerOn.IsEnabled = false;
            poolTime.IsEnabled = false;
                       
            this.dispTimer.Start();

        }

        private void dispTimerEventHandler(object sender, EventArgs e)
        {
            if (flashFlag == false)
            {
                if (torchMode)
                {
                    BitOn();
                    flashFlag = true;
                }
            }
            else
            {
                if (torchMode)
                {
                    BitOff();
                    flashFlag = false;
                }
            }

        }

        private void poolTime_Click(object sender, RoutedEventArgs e)
        {
            if (periodicTimer == null)
            {
                flashOn.IsEnabled = false;
                flashOff.IsEnabled = true;
                timerOn.IsEnabled = false;
                poolTime.IsEnabled = false;

                periodicTimer = ThreadPoolTimer.CreatePeriodicTimer(PoolTimerHandler, TimeSpan.FromMilliseconds(Convert.ToDouble(tspan.Text)), DestroyPoolTmrHandler);
               
            }
        }

        private void PoolTimerHandler(ThreadPoolTimer timer)
        {
            if (flashFlag == false)
            {
                if (torchMode)
                {
                    BitOn();
                    flashFlag = true;
                }
            }
            else
            {
                if (torchMode)
                {
                    BitOff();
                    flashFlag = false;
                }
            }

        }

        private void DestroyPoolTmrHandler(ThreadPoolTimer dTimer)
        {
            dTimer.Cancel();
           
        }


        // Sample code for building a localized ApplicationBar
        //private void BuildLocalizedApplicationBar()
        //{
        //    // Set the page's ApplicationBar to a new instance of ApplicationBar.
        //    ApplicationBar = new ApplicationBar();

        //    // Create a new button and set the text value to the localized string from AppResources.
        //    ApplicationBarIconButton appBarButton = new ApplicationBarIconButton(new Uri("/Assets/AppBar/appbar.add.rest.png", UriKind.Relative));
        //    appBarButton.Text = AppResources.AppBarButtonText;
        //    ApplicationBar.Buttons.Add(appBarButton);

        //    // Create a new menu item with the localized string from AppResources.
        //    ApplicationBarMenuItem appBarMenuItem = new ApplicationBarMenuItem(AppResources.AppBarMenuItemText);
        //    ApplicationBar.MenuItems.Add(appBarMenuItem);
        //}
    }
}