code: private void setUpView() {
  
          mBlurRadiusSeekbar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
              @Override
              public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                  mBlurRadiusTextView.setText(mBlurPrefix + progress);
              }
  
              @Override
              public void onStartTrackingTouch(SeekBar seekBar) {
  
              }
  
              @Override
              public void onStopTrackingTouch(SeekBar seekBar) {
  
              }
          });
  
          mDownScaleFactorSeekbar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
              @Override
              public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                  mDownScaleFactorTextView.setText(mDownScalePrefix + progress);
              }
  
              @Override
              public void onStartTrackingTouch(SeekBar seekBar) {
  
              }
  
              @Override
              public void onStopTrackingTouch(SeekBar seekBar) {
  
              }
          });
  
          mBlurPrefix = getString(R.string.activity_sample_blur_radius);
          mDownScalePrefix = getString(R.string.activity_sample_down_scale_factor);
  
          //set default blur radius to 8.
          mBlurRadiusSeekbar.setProgress(8);
          mDownScaleFactorSeekbar.setProgress(4);
      }
docs: Set up widgets.