I assume you don't want to root the device to accomplish this. In that case, you have two options,
1. Using the MediaProjection provided in android API 21 (Lollipop).
private MediaProjectionManager mProjectionManager;
private static final int DISPLAY_WIDTH = 480;
private static final int DISPLAY_HEIGHT = 640;
private MediaProjection mMediaProjection;
private VirtualDisplay mVirtualDisplay;
private MediaProjectionCallback mMediaProjectionCallback;
private ToggleButton mToggleButton;
private MediaRecorder mMediaRecorder;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
mScreenDensity = metrics.densityDpi;
mMediaRecorder = new MediaRecorder();
initRecorder();
prepareRecorder();
mProjectionManager = (MediaProjectionManager) getSystemService
(Context.MEDIA_PROJECTION_SERVICE);
mToggleButton = (ToggleButton) findViewById(R.id.toggle);
mToggleButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
onToggleScreenShare(v);
}
});
mMediaProjectionCallback = new MediaProjectionCallback();
}
@Override
public void onDestroy() {
super.onDestroy();
if (mMediaProjection != null) {
mMediaProjection.stop();
mMediaProjection = null;
}
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode != PERMISSION_CODE) {
Log.e(TAG, "Unknown request code: " + requestCode);
return;
}
if (resultCode != RESULT_OK) {
Toast.makeText(this,
"Screen Cast Permission Denied", Toast.LENGTH_SHORT).show();
mToggleButton.setChecked(false);
return;
}
mMediaProjection = mProjectionManager.getMediaProjection(resultCode, data);
mMediaProjection.registerCallback(mMediaProjectionCallback, null);
mVirtualDisplay = createVirtualDisplay();
mMediaRecorder.start();
}
public void onToggleScreenShare(View view) {
if (((ToggleButton) view).isChecked()) {
shareScreen();
} else {
mMediaRecorder.stop();
mMediaRecorder.reset();
Log.v(TAG, "Recording Stopped");
stopScreenSharing();
initRecorder();
prepareRecorder();
}
}
private void shareScreen() {
if (mMediaProjection == null) {
startActivityForResult(mProjectionManager.createScreenCaptureIntent(), PERMISSION_CODE);
return;
}
mVirtualDisplay = createVirtualDisplay();
mMediaRecorder.start();
}
private void stopScreenSharing() {
if (mVirtualDisplay == null) {
return;
}
mVirtualDisplay.release();
//mMediaRecorder.release();
}
private VirtualDisplay createVirtualDisplay() {
return mMediaProjection.createVirtualDisplay("MainActivity",
DISPLAY_WIDTH, DISPLAY_HEIGHT, mScreenDensity,
DisplayManager.VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR,
mMediaRecorder.getSurface(), null /*Callbacks*/, null /*Handler*/);
}
private class MediaProjectionCallback extends MediaProjection.Callback {
@Override
public void onStop() {
if (mToggleButton.isChecked()) {
mToggleButton.setChecked(false);
mMediaRecorder.stop();
mMediaRecorder.reset();
Log.v(TAG, "Recording Stopped");
initRecorder();
prepareRecorder();
}
mMediaProjection = null;
stopScreenSharing();
Log.i(TAG, "MediaProjection Stopped");
}
}
private void prepareRecorder() {
try {
mMediaRecorder.prepare();
} catch (IllegalStateException e) {
e.printStackTrace();
finish();
} catch (IOException e) {
e.printStackTrace();
finish();
}
}
private void initRecorder() {
mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.SURFACE);
mMediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
mMediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.H264);
mMediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
mMediaRecorder.setVideoEncodingBitRate(512 * 1000);
mMediaRecorder.setVideoFrameRate(30);
mMediaRecorder.setVideoSize(DISPLAY_WIDTH, DISPLAY_HEIGHT);
mMediaRecorder.setOutputFile("/sdcard/capture.mp4");
}
2. Capturing screen shots continuously, and combine them all to generate video using FFMPEG or any third party libraries.
if (Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState())) {
File sdCard = Environment.getExternalStorageDirectory();
File directory = new File(sdCard.getAbsolutePath() + "/ScreenShots");
directory.mkdirs();
String filename = "screenshot_" + i + ".png";
File imageFile = new File(directory, filename);
// Supports for better capturing (say Keyboard etc) in case your device is rooted
try {
Process sh = Runtime.getRuntime().exec("su", null, null);
OutputStream os = sh.getOutputStream();
os.write(("/system/bin/screencap -p " + "/sdcard/ScreenShots/" + filename).getBytes("ASCII"));
os.flush();
os.close();
sh.waitFor();
i++;
} catch (Exception e) {
e.printStackTrace();
}
}
Hope this helps!