Programmatic screencapture on mobile device

Question

I would like to implement some sort of remote assistance tool (like vnc) for Android. Is there the possibility to capture a screen programmatically on the device?

score 17 · Answer 1 · answered Aug 27 '10 at 09:12

17

Something like that might work for you:

View v = view.getRootView();
v.setDrawingCacheEnabled(true);
Bitmap b = v.getDrawingCache();

answered Aug 27 '10 at 09:12

DonGru

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2

Thanks, this is just what I needed! I had a similar problem but I only wanted a Bitmap of my app, not the OS UI etc – Waleed Amjad Aug 08 '11 at 16:31

score 12 · Answer 2 · answered Aug 27 '10 at 11:58

12

There is a long discussion of this on android-developers, but the short answer is: You can't programatically take a screenshot of an android device's screen at the moment, unless

You have root access on that phone, or
Your application is a system application

The Android Manifest permission READ_FRAME_BUFFER exists (see the api docs here), but can presently only be used by system applications. There are various reasons for this, one being that it is a security risk. If an background can take a screenshot of the phone's screen at any time, then people could use OCR techniques to sniff user's passwords as they were typed in, among other private information.

So no, a VNC application is not possible at the moment without root. To take a screenshot from your computer (while the phone is plugged in via usb) you can use DDMS.

answered Aug 27 '10 at 11:58

aaronsnoswell

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Based on what you said here, it sounds like that a system application could be installed via non-stock recovery and not necessarily need to the ROM itself be rooted. I haven't heard of any VNC system applications, even 1.75 years after you posted this answer. There are a lot of custom ROM users out there and it seems that there is quite a void there waiting for someone to come along with a good VNC app. – Emmaly May 21 '12 at 06:33
2

Regarding point 2: you have to be more than just a system application (i.e. in the system folder), you have to be signed by OS key, which is much more restrictive. This is the difference between a permission being "signatureOrSystem" and "signature". – Rupert Rawnsley Jun 01 '12 at 12:19

score 7 · Answer 3 · answered Sep 07 '10 at 13:57

7

You can try the following library: http://code.google.com/p/android-screenshot-library/ Android Screenshot Library (ASL) enables to programmatically capture screenshots from Android devices without requirement of having root access privileges. Instead, ASL utilizes a native service running in the background, started via the Android Debug Bridge (ADB) once per device boot.

answered Sep 07 '10 at 13:57

Kuba

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Your answer is very useful to me but when i use this library it keep showing me a toast saying "Native service not found". Have you encountered such a problem if so please do help me. Thanks – Ravi K. Sharma Apr 23 '13 at 08:15

score 3 · Answer 4 · edited May 23 '17 at 11:55

3

I think its possible in kitkat using the adb command for screen capture. You can use this command to record screen as a video

adb shell screenrecord /sdcard/demo.mp4

You can find more details here

you can execute the adb command from your app. Check the answer here

edited May 23 '17 at 11:55

Community

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answered Jan 14 '14 at 11:41

Sagar V.

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Nope. After executing: 'screenrecord --verbose --time-limit 5 /sdcard/recvid.mp4' on the getRuntime().exec() method... The process does run, however I get the error: "Permission Denial: broadcast asks to run as user -1 but is calling from user 0; this requires android.permission.INTERACt_ACROSS_USERS_FULL.." However I've been able to run 'screenrecord --help' just fine! – giannileuani Oct 17 '14 at 02:28

score 1 · Answer 5 · edited Oct 14 '14 at 07:18

put it in onClick ..

Bitmap bitmap = takeScreenshot();
saveBitmap(bitmap);

and write funtcion..

public Bitmap takeScreenshot() {
   View rootView = findViewById(android.R.id.content).getRootView();
   rootView.setDrawingCacheEnabled(true);
   return rootView.getDrawingCache();
}

public void saveBitmap(Bitmap bitmap) {
    File imagePath = new File(Environment.getExternalStorageDirectory() + "/screenshot.png");
    FileOutputStream fos;
    try {
        fos = new FileOutputStream(imagePath);
        bitmap.compress(CompressFormat.PNG, 100, fos);
        fos.flush();
        fos.close();
    } catch (FileNotFoundException e) {
        Log.e("GREC", e.getMessage(), e);
    } catch (IOException e) {
        Log.e("GREC", e.getMessage(), e);
    }
}

score 0 · Answer 6 · answered Feb 28 '14 at 15:27

The VNC-type remote tol does exist for "SOME" android devices (mainly Samsung):
TeamViewer QuickSupport
https://play.google.com/store/apps/details?id=com.teamviewer.quicksupport.market
Dos anyone knows how that tool gets screen capturing, and why it supports only limited set of devices?

Programmatic screencapture on mobile device

6 Answers6

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