How to Close activity ( Still_Image_Camera intent ) in Xamarin.Forms

Question

I'm developing a app, it works "when i take 2 photos with continously, camera will close"

so i launch the camera with "MediaStore.IntentActionStillImageCamera" and it can take photo continuously.

and with Fileobserver, i can count How much photo was took.

The last is i have to close camera automatically with no action when condition is true. but, i tried process.kill, activity.finishactivity.... all failed..

How can I close camera app automatically? in Android 9.0

--code modified ----

all code is in Xamarin.Forms in Application.Android

// MainActivity.cs ( common code is removed )
public class MainActivity : global::Xamarin.Forms.Platform.Android.FormsAppCompatActivity
{
    internal static MainActivity Instance { get; private set; }
    protected override void OnCreate(Bundle savedInstanceState)
    {
        Instance = this;
        global::Xamarin.Forms.Forms.Init(this, savedInstanceState);
        LoadApplication(new App());
    }
}

//OtherClass.cs ( i launch camera app with intent )
public void TakePictureAsync()
{
    Intent intent = new Intent(MediaStore.IntentActionStillImageCamera);
    MainActivity.Instance.StartActivityForResult(intent, 0);
}
//OtherClass.cs ( close activity )

public void ExitActivity()
{
    MainActivity.Instance.FinishActivity(0);
}

Leo Zhu · Accepted Answer · 2019-09-03T01:29:08.697

1

activity.FinishActivity(0);

try to change it to :

MainActivity.Instance.FinishActivity(0);

I simulated your scene with a delay, and it worked:

in page.xaml.cs:

public partial class MainPage: ContentPage
{
    public MainPage()
    {
        InitializeComponent ();

    }

    private void Button_Clicked(object sender, EventArgs e)
    {
        DependencyService.Get<IStartAndCloseCamera>().Open();
    }
}

interface IStartAndCloseCamera.cs :

public interface IStartAndCloseCamera
{
    void Open();
}

in Android poject AndroidStartAndCloseCamera.cs:

[assembly: Dependency(typeof(AndroidStartAndCloseCamera))]
namespace App18.Droid
{
  private int sec = 20;
  System.Threading.Timer _dispatcherTimer;
  class AndroidStartAndCloseCamera : IStartAndCloseCamera
    {
      public void Open()
       {
        TimerCallback timerDelegate = new TimerCallback(Tick);
        Intent intent1 = new Intent(MediaStore.IntentActionStillImageCamera);
        MainActivity.Instance.StartActivityForResult(intent1, 0);
        _dispatcherTimer = new System.Threading.Timer(timerDelegate, null, 0, 1000);
        return true;
       }

    private void Tick(object state)
    {          
       MainActivity.Instance.RunOnUiThread(() =>
        {
            if (sec > 0)
            {
                sec--;
            }
            else
            {
                _dispatcherTimer.Dispose();
                MainActivity.Instance.FinishActivity(0);

            }
        });

    }
   }
}

edited Sep 03 '19 at 01:29

answered Sep 02 '19 at 07:38

Leo Zhu

15,726
1
7
23

@이정원 are all the codes you show above in your MainActivity ? – Leo Zhu Sep 02 '19 at 08:42
@이정원 let's talk [here](https://chat.stackoverflow.com/rooms/198813/talk) – Leo Zhu Sep 02 '19 at 08:57
i'm less than 20 reputation, so i can't talk :( – 이정원 Sep 02 '19 at 09:09
@이정원 ok,where do you call ExitActivity method ?in your OtherClass.cs ? – Leo Zhu Sep 02 '19 at 09:10
ExitActivity called from MainPage.xaml.cs in button, entire progress is 1. start MainPage.Xaml 2. when i clicked button, StartActivity(Still_IMAGE_CAMERA), 3. when i take a photo, count photo with fileobserver 4. when condition is true in fileobserver, Call ExitActivity – 이정원 Sep 02 '19 at 09:16
@이정원 so you use DependencyService in your MainPage.xam.cs ? – Leo Zhu Sep 02 '19 at 09:20
yes, i used dependencyservice, and it is otherClass.cs – 이정원 Sep 02 '19 at 09:24
@이정원 Is the count normal? Successful entry into the ExitActivity method? – Leo Zhu Sep 02 '19 at 09:25
when i call "Console.WriteLine("Something")",if condition true ( take a photo count > 1 ), it works well. – 이정원 Sep 02 '19 at 09:33
@이정원 it's strange,it works well for me when i do with delay,i post the code,and you could hava a look. – Leo Zhu Sep 02 '19 at 09:52
it still not working, could you bring me all code? i guess i'm testing app in samsung m20 and the samsung camera app is problem. – 이정원 Sep 03 '19 at 01:48
not working with dispatchertimer and trying RunOnUiThread now – 이정원 Sep 03 '19 at 01:49
RunOnUiThread is not working, i'm trying to test with other device – 이정원 Sep 03 '19 at 01:56
@이정원 ok,when you use timer with a delay,it still not work ? – Leo Zhu Sep 03 '19 at 01:58
in Samsung m20, i use other camera app instead samsung native camera app, and it works well. the camera app was problem! thank you – 이정원 Sep 03 '19 at 02:01
@이정원 i feel Samsung customizations often have unspeakable problems – Leo Zhu Sep 03 '19 at 02:03

score 0 · Answer 2 · edited Sep 02 '19 at 08:11

0

Try to use 2 alternatives way:

Set finish(); with use of current context
Set setResult(Activity.RESULT.CANCELLED);

edited Sep 02 '19 at 08:11

Hasta Dhana

4,699
7
17
26

answered Sep 02 '19 at 03:35

MIC

111
5

i tried it, Main app is finished, but camera is still working. so when i close the camera, mainapp is initalized – 이정원 Sep 02 '19 at 08:20

How to Close activity ( Still_Image_Camera intent ) in Xamarin.Forms

2 Answers2