Android video app setup background thread

Nigel January 16, 2016 7:28 am

The android video app setup background thread tutorial describes how to create an android handler and thread for that handler.

It is important to setup a background handler to remove time consuming tasks from the main UI thread.

Many of the api’s provided by android camera2 provide support for a background thread handler. So it’s recommended to provide a background thread handler if supported.

This android tutorial will be describing how to create a background thread handler.

Get Code

The code to start this tutorial is on github here

https://github.com/mobapptuts/android_camera2_api_video_app.git Tag camera2-video-back-thread

or you can run this command

git clone https://github.com/mobapptuts/android_camera2_api_video_app.git –branch camera2-video-back-thread

Steps

Setup the background handler

Create two activity members, one for the handler and one for the thread

private HandlerThread mBackgroundHandlerThread;
private Handler mBackgroundHandler;

Create start & stop background thread methods

  private void startBackgroundThread() {
        mBackgroundHandlerThread = new HandlerThread("Camera2VideoImage");
        mBackgroundHandlerThread.start();
        mBackgroundHandler = new Handler(mBackgroundHandlerThread.getLooper());
    }

    private void stopBackgroundThread() {
        mBackgroundHandlerThread.quitSafely();
        try {
            mBackgroundHandlerThread.join();
            mBackgroundHandlerThread = null;
            mBackgroundHandler = null;
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

Add the start & stop background thread methods to the android activity onResume & onPause methods

 @Override
    protected void onResume() {
        super.onResume();

        startBackgroundThread();

        if(mTextureView.isAvailable()) {
            setupCamera(mTextureView.getWidth(), mTextureView.getHeight());
        } else {
            mTextureView.setSurfaceTextureListener(mSurfaceTextureListener);
        }
    }

    @Override
    protected void onPause() {
        closeCamera();

        stopBackgroundThread();

        super.onPause();
    }