Screencast Streaming

Overview

StraaS Streaming SDK provides screencast feature to stream your screen contents into StraaS!

Getting Started

This shows you how to start a screencast streaming step by step. You should read Streaming first for the basic knowledge of StraaS Streaming SDK or javadoc for more detail about the code this page mentions below.

Include

Add dependency on jCenter using Gradle.

X.X.X is your preferred version, the screencast feature is bundled with StraaS Streaming SDK starting from version 0.8.0 and only support for Android Lollipop 5.0 devices above.

compile 'io.straas.android.sdk:straas-streaming:X.X.X'

Permission

• Before using screencast streaming, you have to get the permission of microphone, screen capture and system overlay(only for Android M above).

• Get the permission of screen capture

@TargetApi(Build.VERSION_CODES.LOLLIPOP)
public void startScreenCapture(View view) {
    startActivityForResult(mMediaProjectionManager.createScreenCaptureIntent(), REQUEST_MEDIA_PROJECTION);
}

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == REQUEST_MEDIA_PROJECTION && resultCode == Activity.RESULT_OK) {
        // resultCode and data are used to generate media projection
        mResultCode = resultCode;
        mResultData = data;
        ...
    }
}

• Get the permission of system overlay

@TargetApi(Build.VERSION_CODES.M)
private void requestOverlayPermission() {
    Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION,
            Uri.parse("package:" + getPackageName()));
    startActivityForResult(intent, REQUEST_OVERLAY_PERMISSION);
}

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {    
    } else if (requestCode == REQUEST_OVERLAY_PERMISSION && resultCode == Activity.RESULT_OK) {
        // overlay permission granted, can check with Settings.canDrawOverlays
        ...
    }
}

Credential

See Credential

Validate

• To get a StreamManager, you should call StreamManager.initialize(...) with identity and screencast config bundle. This method will check if developer has passed StraaS SDK-Credential and then start our ScreencastService to connect to your declared class implements ScreencastSession interface.

private void startScreenStreaming() {
    ...
    Bundle bundle = new Bundle();
    ...
    // bundle extras will redirect to your declared class implements ScreencastSession
    bundle.putString(EXTRA_LIVE_EVENT_TITLE, mEditTitle.getText().toString());
    bundle.putInt(EXTRA_LIVE_VIDEO_QUALITY, mVideoQuality);
    StreamManager.initialize(MemberIdentity.ME, bundle);
}

• You will get a StreamManager from the onStreamManagerInitComplete callback inside your class implements the ScreencastSession interface if validation succeeds.

@Override
public void onStreamManagerInitComplete(@NonNull Task<StreamManager> task) {
    if (!task.isSuccessful()) {
        ...
    }

    // Valid StreamManager from onStreamManagerInitComplete callback
    mStreamManager = task.getResult();
    ...
}

ScreencastSession

StraaS Streaming SDK has a foreground screencast service, which coordinates all the overlay's interactions. Your app must implement the ScreencastSession interface to supply Notification needed to initialize the foreground service and receive Context and StreamManager from callback later. ScreencastSession is lazily initialized when the onSessionCreate is called and then ready to manage overlay UI. And the valid StreamManager inside ScreencastSession is ready when the onStreamManagerInitComplete callback is invoked and it's used to perform various streaming operations.

The figure below shows the interaction between your streaming app and screencast streaming:

And the code below shows the override functions for ScreencastSession interfaces:

class MyScreencastSession implements ScreencastSession {
    @Override
    public void onSessionCreate(Context context, SessionListener listener, Bundle bundle) {
        // context for this session and bundle for screencast stream config
    }
    @Override
    public void onStreamManagerInitComplete(@NonNull Task<StreamManager> task) {
        if (!task.isSuccessful()) {
            ...
        }

        // Valid StreamManager from onStreamManagerInitComplete callback
        mStreamManager = task.getResult();
        showOverlay();
        prepare();
    }
    @Override
    public NotificationChannel getNotificationChannel() {
        if (!Utils.isAndroidOreoOrAbove()) {
            return null;
        }

        NotificationChannel channel = new NotificationChannel(
                mContext.getString(R.string.screencast_notification_channel_id),
                mContext.getString(R.string.screencast_notification_channel_name),
                IMPORTANCE_LOW);
        channel.setDescription(mContext.getString(R.string.screencast_notification_channel_description));
        return channel;
    }
    @Override
    public Notification getNotification() {
        String title = mContext.getString(R.string.screencast_service_title);
        String subtitle = mContext.getString(R.string.screencast_service_subtitle);

        Notification.Builder builder = new Notification.Builder(mContext)
                .setSmallIcon(R.drawable.straas_icon_white_24px)
                .setContentTitle(title)
                .setContentText(subtitle)
                .setAutoCancel(true);
        if (Utils.isAndroidOreoOrAbove()) {
            builder.setChannelId(mContext.getString(R.string.screencast_notification_channel_id));
        }
        return builder.build();
    }
}

You MUST declare the fully qualified name of the implemented ScreencastSession as a metadata field in AndroidManifest.xml file of your streaming app.

<application>
    ...
    <meta-data
        android:name="io.straas.android.sdk.streaming.SCREENCAST_SESSION_CLASS_NAME"
        android:value="io.straas.android.sdk.streaming.demo.screencast.MyScreencastSession" />
</application>

Prepare

• After getting a StreamManager, you can use prepare(...) to put ScreencastStreamConfig configuration in StreamManager and initialize.
• The parameters of ScreencastStreamConfig can be derived from the bundle extras in onSessionCreate callback.

ScreencastStreamConfig config = new ScreencastStreamConfig.Builder()
        .mediaProjection(mMediaProjection)
        .videoResolution(size.getWidth(), size.getHeight())
        .densityDpi(displayMetrics.densityDpi)
        .build();
			
mStreamManager.prepare(config).addOnSuccessListener(new OnSuccessListener<Void>() {
    @Override
    public void onSuccess(Void void) {
        // Prepare succeeds, ready to use mStreamManager
    }
    }).addOnFailureListener(new OnFailureListener() {
    @Override
    public void onFailure(@NonNull Exception e) {
        //Handle error
    }
});

Start streaming

• See Start streaming

Stop streaming / destroy

• See Stop streaming / destroy

Overlay UI

ControlOverlayLayout and CameraOverlayLayout provides a sample overlay UI for screencast session to interact with user and display camera preview. You can customize your overlay view inside ScreencastSession with the addView and removeView by WindowManager.

private void showOverlay() {
    ...
    mWindowManager.addView(mControlOverlayLayout, mControlOverlayLayout.getParams());        
    mWindowManager.addView(mCameraOverlayLayout, mCameraOverlayLayout.getParams());
}

private void removeOverlay() {
    if (mControlOverlayLayout != null) {
        mWindowManager.removeView(mControlOverlayLayout);
    }
    if (mCameraOverlayLayout != null) {
        mWindowManager.removeView(mCameraOverlayLayout);
    }
    ...
}