I'm working on a project where I collect 4 categories of sensor data via bluetooth low energy and display this data within a tabbed swipe view in individual fragments. Currently I have the BLE functionality fully working, and am receiving values as expected. However, after implementing a Fragment class, a FragmentPagerAdapter class, and the MainActivity, my graphs are not updating with the incoming data.
Right now I'm having trouble determining if I'm not referencing the fragment correctly or if I implemented the GraphView functionality incorrectly. I've tried referencing the GraphView documentation to no avail. Additionally, a TextView within the fragment is updating as expected, it's just that the GraphView never draws any data.
DemoFragment class:
public class DemoFragment extends Fragment {
private TextView textView;
private LineGraphSeries<DataPoint> series;
private GraphView graph;
private int position;
//UpdateSessionData updateIt;
/*public DemoFragment() {
// Required empty public constructor
}*/
public static DemoFragment newInstance(int pos){
Bundle args = new Bundle();
args.putInt("position", pos);
DemoFragment fragment = new DemoFragment();
fragment.setArguments(args);
return fragment;
}
@Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
position = getArguments().getInt("position");
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_demo, container, false);
return view;
}
@Override
public void onViewCreated(View view, Bundle savedInstanceState){
super.onViewCreated(view, savedInstanceState);
graph = (GraphView) view.findViewById(R.id.graph);
textView = view.findViewById(R.id.classification_txt);
graph.getViewport().setScalable(true);
graph.getViewport().setScalableY(true);
graph.getViewport().setScrollable(true);
graph.getViewport().setScrollableY(true);
graph.getViewport().setYAxisBoundsManual(true);
graph.getViewport().setMaxY(4095);
graph.getViewport().setMinY(0);
graph.getViewport().setXAxisBoundsManual(true);
graph.getViewport().setMaxX(100);
graph.getViewport().setMinX(0);
series = new LineGraphSeries<DataPoint>();
graph.addSeries(series);
textView.setText("Classification: " + position);
}
public void addDataPoint(DataPoint point){
series.appendData(point, true, 10000);
graph.refreshDrawableState();
}
/*interface UpdateSessionData{
void updateFragment(int x, int y);
}*/
}
ViewPagerAdapter class:
public class ViewPagerAdapter extends FragmentPagerAdapter {
private String tabTitles[] = new String[] { "O2", "GSR", "HR", "EMG"};
public ViewPagerAdapter(FragmentManager fm){
super(fm);
}
@Override
public Fragment getItem(int position){
return DemoFragment.newInstance(position + 1);
}
@Override
public int getCount(){
return 4;
}
@Nullable
@Override
public CharSequence getPageTitle(int position){
return tabTitles[position];
}
}
Relevant MainActivity code:
@Override
protected void onCreate(Bundle savedInstanceState) {
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
o2frag = DemoFragment.newInstance(0);
ft.add(R.id.pager, o2frag, "o2");
gsrFrag = DemoFragment.newInstance(1);
ft.add(R.id.pager, gsrFrag, "gsr");
hrFrag = DemoFragment.newInstance(2);
ft.add(R.id.pager, hrFrag, "hr");
emgFrag = DemoFragment.newInstance(3);
ft.add(R.id.pager, emgFrag, "emg");
ft.show(emgFrag);
ft.commit();
viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
@Override
public void onPageSelected(int position) {
displayFragment(position);
}
@Override
public void onPageScrollStateChanged(int state) {
}
});
protected void displayFragment(int fragPosition){
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
DemoFragment fragment = (DemoFragment) adapter.getItem(fragPosition);
ft.show(fragment);
ft.commit();
}
@Override
public void onCharacteristicWriteRequest(BluetoothDevice device,
int requestId,
BluetoothGattCharacteristic characteristic,
boolean preparedWrite,
boolean responseNeeded,
int offset,
final byte[] value) {
super.onCharacteristicWriteRequest(device, requestId, characteristic, preparedWrite, responseNeeded, offset, value);
Log.i(TAG, "onCharacteristicWriteRequest "+characteristic.getUuid().toString());
if (UARTProfile.RX_WRITE_CHAR.equals(characteristic.getUuid())) {
//IMP: Copy the received value to storage
storage = value;
if (responseNeeded) {
mGattServer.sendResponse(device,
requestId,
BluetoothGatt.GATT_SUCCESS,
0,
value);
Log.d(TAG, "Received data on "+characteristic.getUuid().toString());
Log.d(TAG, "Received data "+ bytesToHex(value));
}
//IMP: Respond
sendOurResponse();
mHandler.post(new Runnable() {
@Override
public void run() {
//Toast.makeText(LoginActivity.this, "We received data", Toast.LENGTH_SHORT).show();
//Toast.makeText(SessionActivity.this, "We received data: " + bytesToHex(value), Toast.LENGTH_SHORT).show();
short [] dataArray = byteArrayToShortArray(value);
Toast.makeText(SwipeDataActivity.this, "We received data: " + Arrays.toString(dataArray), Toast.LENGTH_SHORT).show();
currentTime = SystemClock.elapsedRealtime();
long elapsedTime = currentTime - startTime;
DataPoint [] points = new DataPoint[4];
for(int i = 0; i < dataArray.length; i++){
points[i] = new DataPoint(currentTime, (long) dataArray[i]);
}
o2frag.addDataPoint(points[0]);
gsrFrag.addDataPoint(points[1]);
hrFrag.addDataPoint(points[2]);
emgFrag.addDataPoint(points[3]);
}
});
}
}
Any help in understanding why the GraphView isn't updating would be greatly appreciated! Thank you in advance for your time, I'm sorry for the large blocks of code but I wanted to make sure the relevant information was available.
