My application makes a webservice call using volley, in order to update recyclerView every 10 seconds. Besides memory usage increase in 10 seconds constantly until it hits the max heap size. Then GC starts doing its job, but the memory usage does not come back down like at the beginning.
Using Eclipse MAT or Android Studio analyzer tasks, I could'nt find a single leak in my code.
I want to know that if there are suspects of leaking in my code. Any help will be appreciated.
Below I have 3 classes:
EventService send a message to MainActivity using sendBroadcast() in every 10 seconds.
MainActiviy will get message from EventService using BroadcastReceiver and calls update operation within its Fragment
EventListFragment, which is inside the MainActivity, contains a RecyclerView, that needs to be updated.
Here is my EventService:
public class EventService extends Service {
private volatile boolean isCanceled = false;
public static final String KEY_MESSAGE = "connection";
public EventService() {}
#Override
public int onStartCommand(final Intent intent, int flags, int startId) {
Runnable r = new Runnable() {
#Override
public void run() {
while (!isCanceled) {
try {
Intent i = new Intent("android.intent.action.MAIN");
AppController.getInstance().cancelPendingRequests("json_obj_req");
i.putExtra(KEY_MESSAGE, MESSAGE);
sendBroadcast(i);
Thread.sleep(10000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
};
Thread eventThread = new Thread(r);
eventThread.start();
return Service.START_STICKY;
}
#Override
public void onDestroy() {
isCanceled = true;
}
#Override
public IBinder onBind(Intent intent) {
return null;
}
}
Here is my MainActivity:
public class MainActivity extends AppCompatActivity {
private Intent intent;
private BroadcastReceiver mReceiver;
private EventListFragment eventListFragment;
private IntentFilter intentFilter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
private void setView() {
eventListFragment = (EventListFragment) getSupportFragmentManager().findFragmentById(R.id.frgEventList);
}
#Override
protected void onResume() {
intent = new Intent(this, EventService.class);
mReceiver = new MyReceiver(eventListFragment);
this.registerReceiver(mReceiver, intentFilter);
intent = new Intent(this, EventService.class);
startService(intent);
}
#Override
protected void onPause() {
super.onPause();
stopService(intent);
unregisterReceiver(mReceiver);
}
private static class MyReceiver extends BroadcastReceiver {
private WeakReference<EventListFragment> eventListFragment = null;
public MyReceiver(EventListFragment eventFragment) {
this.eventListFragment = new WeakReference<>(eventFragment);
}
#Override
public void onReceive(Context context, Intent intent) {
String mssg = intent.getStringExtra(KEY_MESSAGE);
EventListFragment eventFragment = eventListFragment.get();
if (mssg.equals(MESSAGE) && eventFragment != null) {
//Update recyclerView
eventFragment.eventToList();
}
}
}
}
And here is my EventListFragment:
public class EventListFragment extends Fragment {
private View view;
private RecyclerView recyclerView;
private LinearLayoutManager mLayoutManager;
private EventAdapter eventAdapter;
private RequestData requestData;
private ArrayList<EventModel> eventList;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
view = inflater.inflate(R.layout.fragment_event_list, container, false);
return view;
}
#Override
public void onResume() {
super.onResume();
setView();
setControl();
}
private void setView() {
recyclerView = (RecyclerView) view.findViewById(R.id.frg_recycler_view);
}
private void setControl() {
if (eventAdapter == null && mLayoutManager == null) {
eventList = new ArrayList<>();
eventAdapter = new EventAdapter(getActivity().getApplicationContext(), eventList);
mLayoutManager = new LinearLayoutManager(getActivity().getApplicationContext());
recyclerView.setLayoutManager(mLayoutManager);
recyclerView.setHasFixedSize(true);
recyclerView.addItemDecoration(new DividerItemDecoration(getActivity(), LinearLayoutManager.VERTICAL));
recyclerView.setAdapter(eventAdapter);
}
recyclerView.addOnItemTouchListener(new RecyclerItemListener(getActivity().getApplicationContext(), recyclerView, new RecyclerItemListener.RecyclerTouchListener() {
#Override
public void onClickItem(View v, int position) {
EventModel model = eventList.get(position);
SQLiteHandler db = SQLiteHandler.getInstance(getActivity().getApplicationContext());
//some instances
}
#Override
public void onLongClickItem(View v, int position) {
}
}));
}
//make service call
public void eventToList() {
if (requestData == null) {
requestData = new RequestData(getActivity());
}
final ArrayList<EventModel> newList = new ArrayList<>(); //are you leaking?
requestData.getEventToday(new RequestData.VolleyCallback() {
#Override
public void onSuccess(JSONObject result) {
for (int i = 0; i < result.length(); i++) {
try {
JSONObject item = result.getJSONObject(Integer.toString(i));
EventModel eventModel = new EventModel();
String title = item.getString("title");
String start = item.getString("start");
String end = item.getString("end");
String date = item.getString("date");
eventModel.setDate(date);
eventModel.setStartTime(start);
eventModel.setEndTime(end);
eventModel.setTitle(title);
newList.add(eventModel);
} catch (JSONException e) {
e.printStackTrace();
}
}
eventAdapter.update(newList);
}
});
}
}
Many thanks!
First of all, a design consideration: is it necessary to call web service every 10 seconds? Do you know when/how often server data changes?
Every time you read data from web server, application have to do a lot of work: you create many object, update the adapter etc. Moreover, think about network traffic, you use network every 10 seconds.
There are somethings you can do:
Increment wait time: in this way, you reduce the number of created object/per seconds.
Reduce local reference for temporary objects (see following code)
Check if recycler view's adapter, before add new values, the old ones was correctly deferred.
Evaluate if it is possible to use technology to push data, you to avoid data polling. You can see GCM.
For consideration #2, i try rewrite eventToList method:
public void eventToList() {
if (requestData == null) {
requestData = new RequestData(getActivity());
}
requestData.getEventToday(new RequestData.VolleyCallback() {
#Override
public void onSuccess(JSONObject result) {
ArrayList<EventModel> newList = new ArrayList<>();
JSONObject item;
EventModel eventModel;
String title;
String start;
String end;
String date;
for (int i = 0; i < result.length(); i++) {
try {
item = result.getJSONObject(Integer.toString(i));
eventModel = new EventModel();
title = item.getString("title");
start = item.getString("start");
end = item.getString("end");
date = item.getString("date");
eventModel.setDate(date);
eventModel.setStartTime(start);
eventModel.setEndTime(end);
eventModel.setTitle(title);
newList.add(eventModel);
} catch (JSONException e) {
e.printStackTrace();
}
}
eventAdapter.update(newList);
}
});
}
Related
I have a problem with my RecyclerView.
I have a ProductDetailActivity which shows the detail of a product and i have a RecyclerView with its adapter in it.
The user can click on the give rating button which navigates to the RatingActivity where you can give a rating to the product.
The problem is that when i submit my rating and automatically go back to my RatingActivity, the RecyclerView does not get the recently added rating. i have to go back to my productlist and reclick on the product to see the recently added rating.
Here is my code:
ProductDetailActivity:
public class ProductDetailActivity extends AppCompatActivity {
public AppDatabase appDatabase;
private static final String DATABASE_NAME = "Database_Shop";
private RecyclerView mRecycleviewRating;
private RatingAdapter mAdapterRating;
private Button btnGoToRatingActivity;
List<Rating> ratings;
Product p;
int id;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_product_detail);
appDatabase = Room.databaseBuilder(getApplicationContext(),AppDatabase.class,DATABASE_NAME)
.allowMainThreadQueries()
.fallbackToDestructiveMigration()
.build();
btnGoToRatingActivity = findViewById(R.id.btn_goToRatingActivity);
Intent intent = getIntent();
id = intent.getIntExtra("productid", -1);
// pour montrer tous les ratings d'un produit, tu fais un getall
p = appDatabase.productDAO().getProductById(id);
ImageView imageView = findViewById(R.id.imageDetail);
TextView textViewName = findViewById(R.id.txt_nameDetail);
TextView textViewAuthor = findViewById(R.id.txt_authorDetail);
TextView textViewCategory = findViewById(R.id.txt_categoryDetail);
TextView textViewDetail = findViewById(R.id.txt_descriptionDetail);
Picasso.get().load(p.getProductImage()).fit().centerInside().into(imageView);
textViewName.setText(p.getProductName());
textViewAuthor.setText(p.getProductAuthor());
textViewCategory.setText(p.getProductCategory());
textViewDetail.setText(p.getProductDescription());
ratings = appDatabase.ratingDAO().getRatingByProductId(id);
mRecycleviewRating = findViewById(R.id.recyclerRating_view);
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
linearLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
mRecycleviewRating.setLayoutManager(linearLayoutManager);
//recyclerView.setLayoutManager(new LinearLayoutManager(this));
mAdapterRating = new RatingAdapter(ratings);
mRecycleviewRating.setAdapter(mAdapterRating);
btnGoToRatingActivity.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent i = new Intent(ProductDetailActivity.this, RatingActivity.class);
i.putExtra("productid", p.getProduct_id());
startActivity(i);
}
});
mAdapterRating.notifyDataSetChanged();
}
#Override
public void onResume() {
super.onResume();
ratings = appDatabase.ratingDAO().getRatingByProductId(id); // reload the items from database
mAdapterRating.notifyDataSetChanged();
System.out.println(mAdapterRating.ratings.size());
}
}
RatingActivity:
public class RatingActivity extends AppCompatActivity implements RatingGiveFragment.RatingListener {
RelativeLayout mRelativeLayout;
private Button btnConfirmRating;
private EditText mComment;
private RatingBar mRatingBar;
public AppDatabase appDatabase;
private RatingAdapter mAdapter;
List<Rating> ratings;
private static final String DATABASE_NAME = "Database_Shop";
Product p;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_rating);
appDatabase = Room.databaseBuilder(getApplicationContext(),AppDatabase.class,DATABASE_NAME)
.allowMainThreadQueries()
.fallbackToDestructiveMigration()
.build();
int idProduct = RatingActivity.this.getIntent().getIntExtra("productid",-1);
p = appDatabase.productDAO().getProductById(idProduct);
mRatingBar = findViewById(R.id.rating_bar);
mComment = findViewById(R.id.txt_insertOpinionText);
mRelativeLayout = findViewById(R.id.activity_rating);
btnConfirmRating = findViewById(R.id.buttonConfirmRating);
mAdapter = new RatingAdapter(ratings);
btnConfirmRating.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if(!checkEmptyFields()) {
Rating rating = new Rating(p.getProduct_id(),UserConnected.connectedUser.getUser_id(),mRatingBar.getRating(), UserConnected.connectedUser.getUsername(), mComment.getText().toString());
appDatabase.ratingDAO().insertRating(rating);
mAdapter.notifyDataSetChanged();
finish();
}else{
Toast.makeText(RatingActivity.this, "Empty Fields", Toast.LENGTH_SHORT).show();
}
}
});
}
/*private class insertRating extends AsyncTask<String,Integer, Integer>
{
#Override
protected Integer doInBackground(String... strings) {
Rating rating = new Rating(Integer.parseInt(strings[0]), Integer.parseInt(strings[1]), Integer.parseInt(strings[2]), strings[3], strings[4]);
appDatabase.ratingDAO().insertRating(rating);
return 1;
}
#Override
protected void onPostExecute(Integer integer) {
super.onPostExecute(integer);
if (integer == 1)
{
Toast.makeText(getApplicationContext(), getString(R.string.createRating), Toast.LENGTH_SHORT).show();
}
}
}*/
#Override
public void ratingChanged(int newRating) {
RatingTextFragment textFragment = (RatingTextFragment) getSupportFragmentManager().findFragmentById(R.id.fmt_text);
textFragment.setRating(newRating);
}
private boolean checkEmptyFields(){
if(TextUtils.isEmpty(mComment.getText().toString())){
return true;
}else{
return false;
}
}
}
RatingAdapter:
public class RatingAdapter extends RecyclerView.Adapter<RatingAdapter.RatingViewHolder> {
List<Rating> ratings;
public RatingAdapter(List<Rating> ratings){
this.ratings = ratings;
}
#NonNull
#Override
public RatingViewHolder onCreateViewHolder(#NonNull ViewGroup viewGroup, int i) {
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.rating_row,viewGroup, false);
return new RatingViewHolder(view);
}
#Override
public void onBindViewHolder(#NonNull RatingViewHolder ratingViewHolder, int position) {
ratingViewHolder.ratingUsername.setText(ratings.get(position).getRatingUsername());
ratingViewHolder.ratingNumber.setText(String.valueOf(ratings.get(position).getRatingNumber()) + "/5");
ratingViewHolder.ratingComment.setText(ratings.get(position).getRatingText());
}
#Override
public int getItemCount() {
return ratings.size();
}
public static class RatingViewHolder extends RecyclerView.ViewHolder{
public TextView ratingUsername;
public TextView ratingNumber;
public TextView ratingComment;
public RatingViewHolder(#NonNull View itemView) {
super(itemView);
ratingUsername = itemView.findViewById(R.id.txt_usernamerating);
ratingNumber = itemView.findViewById(R.id.num_rating);
ratingComment = itemView.findViewById(R.id.txt_ratingComment);
}
}
}
Pictures:
You get no update in the ProductDetailActivity because you are not updating the data object ratings in the ProductDetailActivity that is the basis for the RatingAdapter.
It would be better to use startActivityForResult in the onClick()method of the ProductDetailActivity. Then you need to override the onActivityResult() method in the ProductDetailActivity. Evaluate the return values and update your data source if necessary, then call notifyDataSetChanged.
This is just pseudo code!
Changes to ProductDetailActivity:
btnGoToRatingActivity.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent i = new Intent(ProductDetailActivity.this, RatingActivity.class);
i.putExtra("productid", p.getProduct_id());
// with this you are telling the activity to expect results and..
//..to deal with them in onActivityResult
startActivityForResult(i, 1);
}
});
// You do not need this next line because setting the adaper triggers the first
//mAdapterRating.notifyDataSetChanged();
}
Add the onActivityResult() method to the ProductDetailActivity.
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == 1) {
if(resultCode == Activity.RESULT_OK){
// trigger a method to update the data object that is linked to the adapter
ratings = appDatabase.ratingDAO().getRatingByProductId(id);
// and now that the data has actually been updated you can call notifyDataSetChanged!!
mAdapterRating.notifyDataSetChanged();
}
if (resultCode == Activity.RESULT_CANCELED) {
//Probably do nothing or make a Toast "Canceled"??
}
}
}
Changes to RatingActivity:
btnConfirmRating.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if(!checkEmptyFields()) {
// I will just assume this works!
Rating rating = new Rating(p.getProduct_id(),UserConnected.connectedUser.getUser_id(),mRatingBar.getRating(), UserConnected.connectedUser.getUsername(), mComment.getText().toString());
appDatabase.ratingDAO().insertRating(rating);
Intent intent = new Intent();
//If you need to return some value.. do it here other you do not need it
//intent.putExtra("result", result);
setResult(Activity.RESULT_OK, intent);
finish();
}else{
Toast.makeText(RatingActivity.this, "Empty Fields", Toast.LENGTH_SHORT).show();
}
}
});
Please be aware in RatingActivity that in btnConfirmRating.setOnClickListener notifying the adapter with mAdapter.notifyDataSetChanged(); does nothing: firstly, because the adapter in the RatingActivity has nothing to do with the adapter in the ProductDetailActivity; secondly: you call finish(); in the next line of code.
I am fetching data from json with Volley and populating RecyclerView with the parsed data but I ran into a bit of problem:
The call to get the items is in onCreate method, so the call is repeated each time the activity is recreated both from configuration changes and otherwise; hence the data is reloaded. So I found this answer that uses parcelables
and this article on Codepath (still on parcelables). After I have followed the instructions explicitly (or so I feel), there seems to be no change: the call to get data is repeated each time the activity is recreated.
FruitItems
public class FruitItems implements Parcelable {
private String fruit_title;
private String fruit_description;
private String fruit_image;
public String getFruit_title() {
return fruit_title;
}
public void setFruit_title(String fruit_title) {
this.fruit_title = fruit_title;
}
public String getFruit_description() {
return fruit_description;
}
public void setFruit_description(String fruit_description) {
this.fruit_description = fruit_description;
}
public String getFruit_image() {
return fruit_image;
}
public void setFruit_image(String fruit_image) {
this.fruit_image = fruit_image;
}
#Override
public int describeContents() {
return 0;
}
#Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(this.fruit_title);
dest.writeString(this.fruit_description);
dest.writeString(this.fruit_image);
}
public FruitItems() {
}
protected FruitItems(Parcel in) {
this.fruit_title = in.readString();
this.fruit_description = in.readString();
this.fruit_image = in.readString();
}
public static final Parcelable.Creator<FruitItems> CREATOR = new Parcelable.Creator<FruitItems>() {
#Override
public FruitItems createFromParcel(Parcel source) {
return new FruitItems(source);
}
#Override
public FruitItems[] newArray(int size) {
return new FruitItems[size];
}
};
}
MainActivity
public class MainActivity extends AppCompatActivity {
private final String TAG = "MainActivity";
private final String KEY_POST_ITEMS = "fruititems";
//List of fruits
private List<FruitItems> mFruitItemsList;
//Views
private RecyclerView recyclerView;
private RecyclerView.Adapter adapter;
private ProgressDialog mProgressDialog;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.d(TAG, "onCreate called");
//Initializing Views
recyclerView = (RecyclerView) findViewById(R.id.fruit_recycler);
LinearLayoutManager layoutManager = new LinearLayoutManager(this);
recyclerView.setLayoutManager(layoutManager);
if (savedInstanceState != null && savedInstanceState.containsKey(KEY_POST_ITEMS)) {
mFruitItemsList = savedInstanceState.getParcelableArrayList(KEY_POST_ITEMS);
} else {
//Initializing the fruitlist
mFruitItemsList = new ArrayList<>();
if (NetworkCheck.isAvailableAndConnected(this)) {
getData();
} else {
final Context mContext;
mContext = this;
final AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this);
alertDialogBuilder.setTitle(R.string.alert_titl);
alertDialogBuilder.setCancelable(false);
alertDialogBuilder.setIcon(R.mipmap.ic_launcher);
alertDialogBuilder.setMessage(R.string.alert_mess);
alertDialogBuilder.setPositiveButton(R.string.alert_retry, new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
if (!NetworkCheck.isAvailableAndConnected(mContext)) {
alertDialogBuilder.show();
} else {
getData();
}
}
});
alertDialogBuilder.setNegativeButton(R.string.alert_cancel, new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
finish();
}
});
alertDialogBuilder.show();
}
}
adapter = new FruitAdapter(mFruitItemsList, this);
recyclerView.setAdapter(adapter);
}
#Override
public void onSaveInstanceState(Bundle savedInstanceState) {
savedInstanceState.putParcelableArrayList(KEY_POST_ITEMS, ArrayList<? extends Parcelable>))mFruitItemsList);
super.onSaveInstanceState(savedInstanceState);
}
//Getting json data
private void getData(){
Log.d(TAG, "getData called");
//Show progress dialog
mProgressDialog = new ProgressDialog(MainActivity.this);
mProgressDialog.setCancelable(false);
mProgressDialog.setMessage(this.getResources().getString(R.string.load_fruit));
mProgressDialog.show();
//Creating a json request
JsonArrayRequest jsonArrayRequest = new JsonArrayRequest(ConfigFruit.GET_URL,
new Response.Listener<JSONArray>() {
#Override
public void onResponse(JSONArray response) {
Log.d(TAG, "onResponse called");
//Dismissing the progress dialog
if (mProgressDialog != null) {
mProgressDialog.hide();
}
//calling method to parse json array
parseData(response);
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
});
//Creating request queue
RequestQueue requestQueue = Volley.newRequestQueue(this);
//Adding request to the queue
requestQueue.add(jsonArrayRequest);
}
//parsing json data
private void parseData(JSONArray array){
Log.d(TAG, "Parsing array");
for(int i = 0; i<array.length(); i++) {
FruitItems fruitItem = new FruitItems();
JSONObject jsonObject = null;
try {
jsonObject = array.getJSONObject(i);
fruitItem.setFruit_title(jsonObject.getString(ConfigFruit.TAG_POST_TITLE));
fruitItem.setFruit_description(jsonObject.getString(ConfigFruit.TAG_POST_DESCRIPTION));
//Parsing image
JSONObject fruitImage = jsonObject.getJSONObject("thumbnail");
fruitItem.setFruit_image(fruitImage.getString("url"));
} catch (JSONException w) {
w.printStackTrace()
}
mFruitItemsList.add(fruitItem);
}
adapter.notifyItemRangeChanged(0, adapter.getItemCount());
}
}
I may not be a pro but I know that I have goofed somewhere in the codes above, else it should have worked.
Now, my question is where did I goof and how do I plug this mistake?
EDIT
I have edited the codes above to reflect the answer that I accepted. It works fine but there is still a problem.
I start Activity B from MainActivity. If I press the back-button in Activity B the data is saved but when I press the up-button, the getData is called again and the data is re-fetched.
Please, is there anyway around this?
You don't seem to have an onSaveInstanceState in your mainactivity. You need something like
#Override
protected void onSaveInstanceState (Bundle outState) {
super.onSaveInstanceState(outState);
outState.putParcelableArrayList(KEY_POST_ITEMS,mFruitItemsList) ;
}
In order to retain your data for the activity that is about to be destructed and the one that is being created, you need to override the onSaveInstance callback
#Override
public void onSaveInstanceState(Bundle savedInstanceState) {
savedInstanceState.putParcelableArrayList(KEY_POST_ITEMS, (ArrayList)mFruitItemsList);
super.onSaveInstanceState(savedInstanceState);
}
NOTE: always remember to call the superclass.
I have developed an app capable of detecting BLE signals and others parameters. I use a BaseAdapter to develop the ListView for showing each item. The problem is that I want to save those data in a xml file when the scan has finished (after a period of time I have established) but I don´t know how to do it.
In this class I do the scan of BLE and is where I want to initiate the process of saving the List when it has passed the time of scanning:
public class ScanBleActivity extends ScanBaseActivity {
private BluetoothAdapter mBluetoothAdapter;
private boolean mScanning;
private Handler mHandler = new Handler();
//private List<BluetoothDevice> mydata;
// Stops scanning after 10 seconds.
private static final long SCAN_PERIOD = 20000;
/* (non-Javadoc)
* #see com.zishao.bletest.ScanBaseActivity#initScanBluetooth()
*/
protected void initScanBluetooth() {
BluetoothManager manager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
mBluetoothAdapter = manager.getAdapter();
startScanLen(true);
}
#Override
protected void onDestroy() {
super.onDestroy();
if (mScanning) {
startScanLen(false);
}
}
/**
*
* #param enable
*/
private void startScanLen(final boolean enable) {
if (enable) {
// Stops scanning after a pre-defined scan period.
mHandler.postDelayed(new Runnable() {
#Override
public void run() {
mScanning = false;
mBluetoothAdapter.stopLeScan(mLeScanCallback);
try {
savedata(true);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}, SCAN_PERIOD);
mScanning = true;
mBluetoothAdapter.startLeScan(mLeScanCallback);
} else {
mScanning = false;
mBluetoothAdapter.stopLeScan(mLeScanCallback);
}
}
And here is my Adapter:
public class LeDeviceListAdapter extends BaseAdapter {
public List<BluetoothDevice> data;
private Activity context;
private final HashMap<BluetoothDevice, Integer> rssiMap = new HashMap<BluetoothDevice, Integer>();
public LeDeviceListAdapter(Activity context, List<BluetoothDevice> data) {
this.data = data;
this.context = context;
}
//public static List<BluetoothDevice> getAllData() {
// return data;
//}
public synchronized void addDevice(BluetoothDevice device, int rssi) {
if(!data.contains(device) ){
data.add(device);
}
rssiMap.put(device, rssi);
}
#Override
public int getCount() {
return data.size();
}
#Override
public Object getItem(int position) {
return data.get(position);
}
#Override
public long getItemId(int position) {
return position;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
if (null == convertView) {
LayoutInflater mInflater =
(LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = mInflater.inflate(R.layout.leaf_devices_list_item, null);
convertView.setTag(new DeviceView(convertView));
}
DeviceView view = (DeviceView) convertView.getTag();
view.init((BluetoothDevice) getItem(position));
return convertView;
}
public class DeviceView {
private TextView title;
private TextView status;
private TextView type;
private TextView address;
private TextView rssivalue;
public DeviceView(View view) {
title = (TextView) view.findViewById(R.id.device_name);
status = (TextView) view.findViewById(R.id.device_status_txt);
type = (TextView) view.findViewById(R.id.device_type_txt);
address = (TextView) view.findViewById(R.id.device_address_txt);
rssivalue = (TextView) view.findViewById(id.signal_intensity_txt);
}
public void init(BluetoothDevice device) {
title.setText(device.getName());
address.setText(device.getAddress());
setType(device.getType());
setStatus(device.getBondState());
rssivalue.setText(""+rssiMap.get(device)+" dBm");
}
public void setType(int status) {
switch(status) {
case BluetoothDevice.DEVICE_TYPE_CLASSIC:
type.setText("Bluetooth Signal");
break;
case BluetoothDevice.DEVICE_TYPE_LE:
type.setText("BLE Signal");
break;
case BluetoothDevice.DEVICE_TYPE_DUAL:
type.setText("Dual Mode - BR/EDR/LE");
break;
case BluetoothDevice.DEVICE_TYPE_UNKNOWN:
type.setText("Device Unknown");
break;
}
}
public void setStatus(int s) {
switch(s) {
case BluetoothDevice.BOND_NONE:
status.setText("Not Bonded");
break;
case BluetoothDevice.BOND_BONDED:
status.setText("Bonded");
break;
case BluetoothDevice.BOND_BONDING:
status.setText("Bonding");
break;
}
}
}
I want to save the title, address, type, status and rssivalue (shown in the code above) of each BLE signal that has been found during the scan to be saved in a xml file. I have provided only a part of the project but if it is necessarly I will edit and put the code that is missing.
Does anyone know how to do it?? Please help!!!!!
New code: This corresponds to the class ScanBaseActivity:
abstract public class ScanBaseActivity extends ListActivity {
protected LeDeviceListAdapter mLeDeviceListAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_devices_scan);
mLeDeviceListAdapter = new LeDeviceListAdapter(this, new ArrayList<BluetoothDevice>());
this.setListAdapter(mLeDeviceListAdapter);
initScanBluetooth();
}
/**
* Start Scan Bluetooth
*
*/
abstract protected void initScanBluetooth();
#Override
protected void onListItemClick(ListView l, View v, int position, long id) {
BluetoothDevice device = (BluetoothDevice) mLeDeviceListAdapter.getItem(position);
ParcelUuid[] uuids = device.getUuids();
String uuidString = "Getting UUID's from " + device.getName() + ";UUID:";
if (null != uuids && uuids.length > 0) {
uuidString += uuids[0].getUuid().toString();
} else {
uuidString += "empty";
}
Toast.makeText(this, uuidString, Toast.LENGTH_LONG).show();
}
/**
* #param device
*/
protected synchronized void addDevice(final BluetoothDevice device, final int rssi) {
runOnUiThread(new Runnable() {
#Override
public void run() {
mLeDeviceListAdapter.addDevice(device, rssi);
mLeDeviceListAdapter.notifyDataSetChanged();
}
});
}
protected void savedata(boolean enable) throws FileNotFoundException{
String filename = "file.txt";
FileOutputStream fos;
Bundle extras = getIntent().getExtras();
long timestamp = extras.getLong("currentTime");
try {
fos= openFileOutput(filename, Context.MODE_PRIVATE);
ObjectOutputStream out = new ObjectOutputStream(fos);
out.write((int) timestamp);
out.writeObject(mLeDeviceListAdapter);
out.write(null);
out.close();
Toast.makeText(this, R.string.list_saved, Toast.LENGTH_SHORT).show();
savedata(false);
} catch (FileNotFoundException e){
e.printStackTrace();
} catch (IOException e){
e.printStackTrace();
}
}
}
New!!: I have edited ScanBaseActivity and ScanBleActivity to introduce the xml saving but when I run the app, when the scan stops it causes an error (moment when the list has to be saved in the sml file). Does anyone know how to solve it or correct it??!!!
OK, first, you need to re-shape how you are dealing with your adapter, after that, everything should fall into place.
so for that, I'm going to outsource to vogella, the cardinal of good android design patterns
http://www.vogella.com/tutorials/AndroidListView/article.html
you could read up through section 3, eat some copypasta and come back here, but every extra line you grok is a good thing =]
Now you have an activity that has a list of data, and an adapter that takes that list and--somewhat dumbly in comparison to your code--applies it to a view of some sort. When you want to update that data, you do so by modifying the List object in the activity by your method somewhere that gets a list of Bluetoothdevices--and I'd take that process off thread with an AsyncTask.
Since you are passing a List to the adapter, you can wait until you've populated the data in your activity, then do an adapter.notifyDataSetChanged. You do not want to adapter.add
then you have a nice List of your data in the activity; you don't need to worry if it's the right list, because--given the update pattern--it's the only list!
then follow the link Merleverde posted to serialize that data into an xml, maybe in a utility class, but in your activity is fine.
edit:
here is a perfectly good adapter, this is part of the larger pattern that displays dynamically changing data:
public class AnchorListAdapter extends ArrayAdapter<String>
{
private final List<String> anchorNames;
public AnchorListAdapter(Context context, int textviewId, List<String> anchors){
super(context, textviewId, anchors);
anchorNames = anchors;
}
#Override
public String getItem( int i ) {
return anchorNames.get(i).toString();
}
}
Well, it's not that you are going to be saving it from the adapter, it's that the adater is going to be 'adapting' a data set that you will put into preferences.
as a feild:
private SharedPreferences saveHash;
in onCreate:
saveHash = getSharedPreferences( getString( R.string.save_hash ), MODE_PRIVATE );
then later:
public void onFinishedLoading(){
super.onPause();
SharedPreferences.Editor editor = saveHash.edit();
editor.clear();
for( String s: myData){
editor.putString(x, s);
}
editor.commit();
}
edit: realized you want to make a hash from a list; what do you want as the key?
I'm stuck with communication between activity and fragment using interface. I have created activity with child fragment. I wanna do some stuff with continuous thread defined in activity and during that thread when I'm getting some result at that time I wanna trigger to child fragment to do something.
My Container Activity
public class MySpaceActivity extends BaseDrawerActivity {
private OnSetLastSeenListener mListner;
public static Thread mThread = null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
super.setHeaders(Const.MY_SPACE);
super.setSubmenus(Const.MY_SPACE,
Utils.getSubmenuList(Const.MY_SPACE, MySpaceActivity.this),
submenuBean);
// super.attachFragment(submenuBean);
}
#Override
public void setHeaderSubMenu(SubmenuBean subMenuBean) {
// txt_submenu.setText(subMenuBean.getSubmenu_name());
this.submenuBean = subMenuBean;
Log.print("::::: setHeaderSubMenu ::::");
super.attachFragment(submenuBean);
}
public void setsubFragment(SubmenuBean subMenuBean) {
this.submenuBean = subMenuBean;
super.attachSubFragment(submenuBean);
}
#Override
public void onBackPressed() {
super.onBackPressed();
popLastFragment();
}
private void popLastFragment() {
if (super.getNumberOfChilds() > 1) {
super.popSubFragment();
} else {
finish();
}
}
#Override
protected Fragment getFragement() {
StudentsFragment fragment = new StudentsFragment(Const.MY_SPACE,
getSubmenubean());
return fragment;
}
public SubmenuBean getSubmenubean() {
return submenuBean;
}
#Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
mThread = new Thread(new CountDownTimer(MySpaceActivity.this));
mThread.start();
}
#Override
protected void onStop() {
// TODO Auto-generated method stub
super.onStop();
if (mThread.isAlive()) {
mThread.interrupt();
mThread = null;
}
}
public void updateLastSeen(){
Log.print("::::::Call Interface::::::");
mListner.updateLastSeen();
}
class CountDownTimer implements Runnable {
private Context mContext;
private JSONObject mJsonObject;
private JSONArray mJsonArray;
public CountDownTimer(Context mContext) {
this.mContext = mContext;
}
// #Override
public void run() {
while (!Thread.currentThread().isInterrupted()) {
try {
HttpChatLastSeen mChat = new HttpChatLastSeen();
mJsonObject = mChat.Http_ChatLastSeen(mContext);
String mResult = mJsonObject.getString("Result");
if (mResult.equalsIgnoreCase(String
.valueOf(Const.RESULT_OK))) {
mJsonArray = mJsonObject.getJSONArray("UserData");
for (int i = 0; i < mJsonArray.length(); i++) {
mJsonObject = mJsonArray.getJSONObject(i);
new DbStudentMasterBll(mContext).update(
"last_seen", mJsonObject
.getString("LastSeen"), Integer
.parseInt(mJsonObject
.getString("UserId")));
}
} else {
Log.print("MY LAST SEEN Response : "
+ mJsonObject.toString());
}
updateLastSeen();
Thread.sleep(15000);
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
} catch (Exception e) {
Log.print("ChatLastSeenThread : ", e.getMessage());
}
}
}
}
}
My Child Fragment With Interface :
public class StudentsFragment extends Fragment implements OnSetLastSeenListener{
TextView txt_submenu;
ListView list_students;
SubmenuBean submenuBean;
int Mainmenu;
MySpaceActivity mMySpaceActivity;
ArrayList<DbStudentMasterBean> studentsList;
StudentsAdapter mAdapter = null;
OnSetLastSeenListener mListner;
public StudentsFragment() {
super();
}
public StudentsFragment(int Mainmenu, SubmenuBean submenuBean) {
this.submenuBean = submenuBean;
this.Mainmenu = Mainmenu;
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_students, container,
false);
mMySpaceActivity = (MySpaceActivity) getActivity();
txt_submenu = (TextView) view.findViewById(R.id.txt_submenu);
txt_submenu.setText(submenuBean.getSubmenu_name());
txt_submenu.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
mMySpaceActivity.openDrawer();
}
});
list_students = (ListView) view.findViewById(R.id.list_colleagues);
studentsList = new DbStudentMasterBll(getActivity()).getAllRecords();
mAdapter = new StudentsAdapter(getActivity(), studentsList, handler);
list_students.setAdapter(mAdapter);
list_students.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
DbStudentMasterBean bean = (DbStudentMasterBean) parent
.getAdapter().getItem(position);
Message msg = new Message();
msg.what = CHAT;
msg.obj = bean;
handler.sendMessage(msg);
}
});
return view;
}
Handler handler = new Handler() {
public void handleMessage(android.os.Message msg) {
switch (msg.what) {
case CHAT:
submenuBean.setTag(VIEWCHATSTUDENT);
DbStudentMasterBean bean = (DbStudentMasterBean) msg.obj;
mMySpaceActivity.setsubFragment(submenuBean);
break;
}
};
};
#Override
public void updateLastSeen() {
// TODO Auto-generated method stub
Log.print("!!!!!!!!!Refresh Adapter!!!!!!!!!!!");
mAdapter.notifyDataSetChanged();
}
}
My Interface :
public interface OnSetLastSeenListener {
public void updateLastSeen();
}
So I have implemented interface OnSetLastSeenListener with my child fragment StudentsFragment . Now I'm calling method of tht interface updateLastSeen() from my container activity with thread. But it is not getting trigger to child fragment where I have implemented interface. So I don't know whether it is good way to communicate or not? Let me take your help to suggest on this solution or best way to communicate from child fragment to parent activity.
Thanks,
It is better to use interface when you want to communicate something from Fragment to Activity and not vice versa.
In your case, you can directly call the method in Fragment from Activity through fragment object. No need to use interface.
Something like this (For static fragments)
StudentsFragment fragment = (StudentsFragment) getFragmentManager()
.findFragmentById(R.id.fragmentid);
if (fragment != null && fragment.isInLayout()) {
fragment.updateLastSeen();
}
For dynamic fragment you can use the fragment object directly.
First of all, I am relatively new to android programming.
I am creating a ViewPager application with two Fragments. One of the Fragments requests data from a server and return a result to the main FragmentActivity. My problem is that this request to the server can take sometime, and I have been trying to get a ProgressDialog to appear with AsyncTask while the user waits for the data to be retrieved. Once I create the background thread to retrieve the data, I successfully execute some code in the onPostExecute() method and set some variables. However, the return statement that sends information back to the FragmentActivity is being executed before the background thread actually ends. I can't seem to figure out a way for the main thread to wait on the background thread. Using Asyctask's get() method results in the ProgressDialog from appearing. I have looked through a lot of posts in here, but can't seem to find an answer.
Anything helps.
Code below:
SplashScreen.java
public class SplashScreen extends FragmentActivity {
MainMenu mainMenu;
MapScreen mapScreen;
PagerAdapter pagerAdapter;
ViewPager viewPager;
List<LatLng> geoPoints;
private Context context;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_splash_screen);
context = this;
initializePaging();
}
private void initializePaging()
{
mainMenu = new MainMenu();
mapScreen = new MapScreen();
pagerAdapter = new PagerAdapter(getSupportFragmentManager());
pagerAdapter.addFragment(mainMenu);
pagerAdapter.addFragment(mapScreen);
viewPager = (ViewPager) super.findViewById(R.id.viewPager);
viewPager.setAdapter(pagerAdapter);
viewPager.setOffscreenPageLimit(2);
viewPager.setCurrentItem(0);
viewPager.setOnPageChangeListener(new OnPageChangeListener()
{
#Override
public void onPageScrollStateChanged(int postion){}
#Override
public void onPageScrolled(int arg0, float arg1, int arg2){}
#Override
public void onPageSelected(int position)
{
switch(position){
case 0: findViewById(R.id.first_tab).setVisibility(View.VISIBLE);
findViewById(R.id.second_tab).setVisibility(View.INVISIBLE);
break;
case 1: findViewById(R.id.first_tab).setVisibility(View.INVISIBLE);
findViewById(R.id.second_tab).setVisibility(View.VISIBLE);
break;
}
}
});
}
//Called from onClick in main_mainu.xml
public void getDirections(View view)
{
InputMethodManager inputManager = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
inputManager.hideSoftInputFromWindow(getCurrentFocus().getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);
try
{
geoPoints = mainMenu.getDirections(context);
mapScreen.plotPoints(geoPoints);
}
catch(Exception e)
{
Toast.makeText(getApplicationContext(), "Error! Invalid address entered.", Toast.LENGTH_LONG).show();
mainMenu.clear();
}
}
}
MainMenu.java
public class MainMenu extends Fragment {
String testString;
int testInt;
TextView testTV;
private TextView tvDisplay;
private EditText departure;
private EditText destination;
private Geocoder geocoder;
private List<Address> departAddress;
private List<Address> destinationAddress;
private List<LatLng> geoPoints;
private String departString;
private String destinationString;
private Address departLocation;
private Address destinationLocation;
private LatLng departurePoint;
private LatLng destinationPoint;
private Context contextMain;
private GetData task;
public MainMenu()
{
super();
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
View root = (View) inflater.inflate(R.layout.main_menu, null);
geoPoints = new ArrayList<LatLng>(2);
return root;
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState)
{
departure = (EditText) getView().findViewById(R.id.depart_field);
destination = (EditText) getView().findViewById(R.id.destination_field);
tvDisplay = (TextView) getView().findViewById(R.id.textView1);
}
public List<LatLng> getDirections(Context context)
{
contextMain = context;
geocoder = new Geocoder(getActivity());
departString = departure.getText().toString();
destinationString = destination.getText().toString();
try
{
task = new GetData(new Callback(){
public void run(Object result)
{
//return geoPoints;
}
});
task.execute((Void[])null);
}catch(Exception e)
{
e.printStackTrace();
}
return geoPoints;
}
public void clear()
{
departure.setText("");
destination.setText("");
tvDisplay.setText("Enter departure point, and destination point");
}
private class GetData extends AsyncTask<Void, Void, List<List<Address>>>
{
Callback callback;
private ProgressDialog processing;
public GetData(Callback callback)
{
this.callback = callback;
}
#Override
protected void onPreExecute()
{
processing = new ProgressDialog(contextMain);
processing.setTitle("Processing...");
processing.setMessage("Please wait.");
processing.setCancelable(false);
processing.setIndeterminate(true);
processing.show();
}
#Override
protected List<List<Address>> doInBackground(Void...arg0)
{
List<List<Address>> list = new ArrayList<List<Address>>(2);
try
{
departAddress = geocoder.getFromLocationName(departString, 5, 37.357059, -123.035889, 38.414862, -121.723022);
destinationAddress = geocoder.getFromLocationName(destinationString, 5, 37.357059, -123.035889, 38.414862, -121.723022);
list.add(departAddress);
list.add(destinationAddress);
}catch(IOException e)
{
e.printStackTrace();
}
return list;
}
#Override
protected void onPostExecute(List<List<Address>> list)
{
departLocation = list.get(0).get(0);
destinationLocation = list.get(1).get(0);
departurePoint = new LatLng(departLocation.getLatitude(), departLocation.getLongitude());
destinationPoint = new LatLng(destinationLocation.getLatitude(), destinationLocation.getLongitude());
if(geoPoints.size() >= 2)
{
geoPoints.clear();
}
geoPoints.add(departurePoint);
geoPoints.add(destinationPoint);
callback.run(list);
processing.dismiss();
}
}
}
#Override
protected Object doInBackground(Void...arg0)
{
Object result = null;
try
{
departAddress = geocoder.getFromLocationName(departString, 5, 37.357059, -123.035889, 38.414862, -121.723022);
destinationAddress = geocoder.getFromLocationName(destinationString, 5, 37.357059, -123.035889, 38.414862, -121.723022);
}catch(IOException e)
{
e.printStackTrace();
}
return result;
}
You never set the value of result...